School me on supercharging a 360

I have been doing a little thinking on my next project. I have thought about a Viper drivetrain, a elephant Hemi and now a supercharged smallblock. Just weighing all the alternatives and still maintain the wow factor. I am sure most any 360 block would do. But after that I am lost. I figure a forged crank and a girdle would probably be a must along with forged pistons and better rods. Heads I have no clue on. I think something like a 6/71 blower with 2 smaller blow through carbs is probably the ticket. There are other factors that I know nothing about. Ie: exhaust, ignition timing, cam choice and any other items you can think of. One question I have always thought about is, what happens when you get caught in the rain with a blower sticking out of the hood?

I suppose I would be looking for something in the 550 to 600 HP range.

Any help would be appreciated.

Jack

Heads I have no clue on. I think something like a 6/71 blower with 2 smaller blow through carbs is probably the ticket. There are other factors that I know nothing about. Ie: exhaust, ignition timing, cam choice and any other items you can think of. One question I have always thought about is, what happens when you get caught in the rain with a blower sticking out of the hood?

Heads won't matter since your forceing in the air. While yes higher flowing heads will perform better than not and ported even better etc....

A 6/71 will not use "Blow through" carbs. They will use a carb designed to sit up top for best results. The carbs still draw air through themslefs.

Otherwise, the ignition should have a boost retard set up. Supercharger cams. I have seen advice to use a wider centerline cam to help build the pressure up.

Getting caought in the rain? Drive on!

Like I said rumble, I know next to nothing on this type of setup. I thought that all blowers used blow through carbs, but after thinking about it some more, that would be the type of carb a Paxton would use as opposed to a roots type blower would it not?

Wouldn't the blower have a tendancy to suck in rain water if it's sticking out of the hood?

Jack

Why not build a stroker Jack?You can maintain your stock look with a pretty stout smallblock.Anything in the 600hp area I would advise searching for a R3 block.Good Luck with your goals.:read2:

Like I said rumble, I know next to nothing on this type of setup. I thought that all blowers used blow through carbs, but after thinking about it some more, that would be the type of carb a Paxton would use as opposed to a roots type blower would it not?

Wouldn't the blower have a tendancy to suck in rain water if it's sticking out of the hood?

Jack

I personally like a blow-through set up. Something about compressing fuel and detonation happening in something that sticks above the hood line scares the crap out of me! When it comes to forced induction I like to keep the fuel out of the impeller/turbine,just seems safer.But I also prefer turbos to superchargers 9/10 times. V8's have no problem with bottom end torque,which is the only benifit that a supercharger has over a turbo.

As for rain getting in,thats why you run a carb hat with a filter!

Well Jack, I know some basics about doing something like this. The paxton supercharger or a turbo use a blow through carb since that is how it is set up. The supercharger is blowing/forcing air through the carb.

On a 6/71 roots blower, the carbs sit on top of the supercharger and the carbs have air pulled from underneath by the engine/supercharger. They (The aftermarket) have designed carbs for both applications.

You could use just plain ol'stock OOTB carbs, Holley or AFB's on top of the 6/71, but for best results, a carb designbed for this application will get a good bit more power.

Sucking in water isn't a big thing. How much the engine is ingesting is. I see where this is of concern for you. I would not worry about this. If there was any concern (Or care) to being caught in the rain, then a scoop that I could flip around would be my problem solver.

Well Jack, I know some basics about doing something like this. The paxton supercharger or a turbo use a blow through carb since that is how it is set up. The supercharger is blowing/forcing air through the carb.

On a 6/71 roots blower, the carbs sit on top of the supercharger and the carbs have air pulled from underneath by the engine/supercharger. They (The aftermarket) have designed carbs for both applications.

You could use just plain ol'stock OOTB carbs, Holley or AFB's on top of the 6/71, but for best results, a carb designbed for this application will get a good bit more power.

Sucking in water isn't a big thing. How much the engine is ingesting is. I see where this is of concern for you. I would not worry about this. If there was any concern (Or care) to being caught in the rain, then a scoop that I could flip around would be my problem solver.

Turbos can also be draw through!

Blow through carb superchagers can be found here. http://www.vortechsuperchargers.com/

Blowers/6-71's can be found here, they draw air from under the carb. http://blowerdriveservice.com/

6/71 styled "Roots" superchargers are known for lots of torque on demand right now from idle to ....... and there very hard on the crank and it's attaching parts.

The "Hair dryer" styled supercharger and turbos are not as strong from the get go but will come up very well and strong. There intail "Hit" on the engine is softer. There alot easier on the lower end of the engine.

While I like the idea of a turbo, it is a little more complex in building due to more pipeing. I myself have not seen any bolt on kits with brackets and such.

SCDE could really shed some light on this area.

Yes! Indeed they can. When was the last time you seen one muchless seen them or in a kit form.

Its true a turbo is a bit more complex. No kits but its not hard to build one. You can get intercooler kits off of ebay and it comes with an assortment of pipes that you can cut to make work. I have seen guys flip a set of shorty style headers,otherwise you will have to build your own. But rear mount turbos are also an option now.

Yes! Indeed they can. When was the last time you seen one muchless seen them or in a kit form.

Last weekend at a car show on a 65 mustang with an inline 6. I also know of a few of them laying around in friends garages/shops. Also seen a few on some slant sixes runing pretty well.

Do you always build from kits? Scared of a little ingenuity? I would not use a draw through turbo or supercharger like I have stated above,my point was that there are more options than you listed.

"The paxton supercharger or a turbo use a blow through carb since that is how it is set up"

It was this statement that triggered my comment.

I have only seen rear mounted turbos for the trucks, not old school cars. System looked cool though.
An intercooler is a great add on, a bit expensive, but a worthy add on. They can be had for the 6/71's as well. The additional 4 inchs in height aint so great, but that's how they do it.

Rear mounted turbos are not application specific. The make them for Vipers and Vettes,could be easily adapted to and old car. Saw a 68 camaro at a car show with rear mounted turbos,I think it was a year one car or something of the like.

For the intercoler, with a turbo they are cheap. You can get a kit for under 200 with the piping,and its a front mount so you can still see over you hood after you install it:-D


On a side note I saw a bad ass vid on you tube of a guy with a blown 2g Hemi,it was intercooled and you couldnt even see into the car from the front! I guess you dont need to see to go in a straight line huh!

Grinder;1002247]Last weekend at a car show on a 65 mustang with an inline 6. I also know of a few of them laying around in friends garages/shops. Also seen a few on some slant sixes runing pretty well. I'd like a picture of that. It sounds preety cool.
I guess Fla. has a big host of used and outdated systems, I've never seen one layin around here. I have seen 1 or 2 on cars here though. Very old styuff.

Do you always build from kits?
Never have. But then sometimes, the easy way out is not only easy, but all the work is done for you. Sometimes, when you know little or nothing of the system or etc.... This would be a bennifit.

Would I do a kit for a charger system. On a 6/71, not really, just the kit to bolt it all up and get going. No sense of fabing up brackets. Of course, if you want to pound your chest and say "I did it, from scratch" Please, knock yourself out and be proud you took a harder route. Then post pictures for all to see. I await them.

For me, I'll follow the pack and not be ashamed.


Scared of a little ingenuity?

And why would you think that? Because I suggested a kit for the OE poster? Is there something wrong with a kit? Or are you just pounding your chest at me while trying to send me into a corner? F%^&*( off.

I would not use a draw through turbo or supercharger like I have stated above,my point was that there are more options than you listed.

LOL duley noted and a no brainer. That was easy to see. Also easy to see was your confusement of roots chargers being a blow through a carb while there not.
I posted the links to the various places as so not to get the OE poster confused like yourself. Lets keep mis-information down and info correct.


"The paxton supercharger or a turbo use a blow through carb since that is how it is set up"

It was this statement that triggered my comment.

In general and popular useage, that is the way it is done. I never said it couldn't be that way, by why would you do it that way? To be different? Come one now. Stop it. Your splitting hairs like a jerk. Your trying to bust my balls on a hair splitting and seldom used method of superchargeing and carb use. WTF!?!?!

When was the last time you have seen it done as a draw through carb that is offered as a aftermarket set up? What company does this. Some small out of the way shop in the middle of no where?

Well goollly jeee good for them and you.

Maybe, the OE poster wants to do it the easy way instead of fabbing everything up and doing it in a non-main stream way. IDK, I just answered the question. You just wanna start shit.

(I'm outta here)

[QUOTE]Rear mounted turbos are not application specific. The make them for Vipers and Vettes,could be easily adapted to and old car. Saw a 68 camaro at a car show with rear mounted turbos,I think it was a year one car or something of the like.
Never said they were. So, list me a app. for a 68 Dart.


For the intercoler, with a turbo they are cheap. You can get a kit for under 200 with the piping,and its a front mount so you can still see over you hood after you install it:-D
And now your talking kit. Afraid of a little.....

Geez, I didn't want to start a war. LOL

Jack

OK ok - lets calm down a bit guys.... No need to take things personally.




.

shake hands guys. no need to get heated......i think the name calling was a little inappropriate...

Screw him!

Geez, I didn't want to start a war. LOL

Jack

You didn't start a war jack, he started with a few things and got hissy, so I handed it right back. It's an on going thing with him and now he just added more fuel for the fire with personal insults.

All I did was point out that he was wrong with a 6/71 being a S-charger that sucks in/draws in the fuel from under the carb, not blow through and he kept going.

I'm only trying to help or suggest. AND I did say I don't know a whole lot about the subject from the get go.

Read the B.S. again and weed through the stupidness of it all for the infomation pertaining to your wants. Best bet would be to contact a supercharger place and get more info from them. I can't comment much more on what you may need to know about this build your thinnking of.

BlowerDriveService has those nasty stick outta your hood blowers (6/71) and the Supercharger store.com has the hairdryer style superchargers.
For turbos, I'd contact SDCE, (There here on this board) for there advice on doing a turbo set up.

But be careful, GRINDER may call you something less than polite if you whimp out and get a kit.

Geez, I didn't want to start a war. LOL

Jack

I saw this thread earlier today and was afraid to comment although interested.

OK ok - lets calm down a bit guys.... No need to take things personally.

So the edits are fine??

So anyway- I was interested in hearing about the supercharged 360. Any progress there?

The Vortech looks like it would not require the hood scoop, correct? Since it is mounted on the front of the engine... That would solve the rain issue.

That would be correct Jim. Since it is mounted on brackets to the front of the engine, the air intake (Filter) can be placed ethier on the unit itself or moved with tubing.

6pk2go, his posts were over thr top direct assulats. He don't like my mug in the avatar. Most of this could go into the trash.

Did I misread that the OP was looking for some eye candy wow factor appeal also?
Traditional roots style superchargers can be alot of fun on a street car and are very visually impressive. Littlefield, BDS, and Dyer are very good manufacturers of blowers and kits. (Kits? Sorry, why reinvent the wheel when someones done the groundwork?)

Someone had mentioned that heads weren't a big deal. Wrong. With a blower motor, heads can make a big difference. If you can't flow the air you force into the motor, it will build up alot of heat and then you have detonation problems. That will take the fun out of your day. Keep your compression low and try to avoid "blower" cams on a street motor running on pump gas.

If you want to build it, do it. Just do your homework first and you will be happy with a killer motor.

. Keep your compression low and try to avoid "blower" cams on a street motor running on pump gas.

If you want to build it, do it. Just do your homework first and you will be happy with a killer motor.

Okay- new guy here so bear with me. What type of cam would you use on a supercharged 'street /driver' motor?

And why keep compression low? What do you call low? Is it in relation to the amount of boost?

(Kits? Sorry, why reinvent the wheel when someones done the groundwork?)
I hear ya there, but be careful of Grinder will grind you and then say use'em.


Someone had mentioned that heads weren't a big deal. Wrong. With a blower motor, heads can make a big difference. If you can't flow the air you force into the motor, it will build up alot of heat and then you have detonation problems.
That would be me. Regulate the boost and timing and this isn't a problem from how I understand it. Reguardless, your forcing the air through, so the heads flow isn't as critical as a N/A engine.

Of course, the search for more power would leed to ported heads and maybe higher PSI?

If you want to build it, do it. Just do your homework first and you will be happy with a killer motor.
I so agree. Just do the homework and build it!

ok i didnt read all the previous hoopla,,

but i do know a little about street blowers,,and before i type a hole bunch of stuff,, ill say this last time ( few weeks ago) same topic,,went back and forth, at the end the person asking the same questions had this to say,,

' ILL HAVE TO SAVE MY PENNIES A WHILE, ITS LIKE 6 TO 8 GRAND TO DO THIS '

read it and read it again,,a average roots style blower motor for the street that is going to start,and run with out coaxing the throttle till the blower builds some heat in it to idle ,,because its costs to much to set the carbs up properly ...

now if you want a complete ready turn key blower motor for the streeet thats affordable go to BIG ALS TOY BOX web site,, he builds all makes,, he is not just a chevy guy,,and that what you are going to find at your local speed/machine shop.,

there are several stand alone items you will need that your not going to find used for a small block mopar,,at your local swap meet,, so gettign a complete set up,with carbs set up properly,,pullys that make every thing line up,, and an intake,, the price of an almost true blower intake alone will make you re think all this,,,

if you decide this is for you and your serious make sure you run a harmonic balancer,,an after market one not a 2 piece factory balancer,, it makes a difference when getting all the pullys worked out,,

i was lucky enough back in the mid 1990s to find my set up used pieces here and there that were all on this motor at one time,,,

i consider my engine almost bullit proof,,was built at an engine shop not a chevy shop,,,my block was re worked X block,, because the orignal owner of this block took it to a chevy speed shop,,and it was butchered, it was a new X block

i took it to a race shop that builds roundy round motors,,they know how to make a motor live,,, they build motors for people like kinser,,,

this motor is a mild street motor and in the mis 90s was 6 grand,including the used parts i was lucky enough to locate,,but didnt enclude blower carbs,,

if 600 HP is what your after easy with a blower,, but also easy with a 360 stroker,,and probably less money,,

if your seriuous ill tel you what ive been able to learn,,about building it properly,,by all meens if you call BDS,,, use your own judgement,,

Okay- new guy here so bear with me. What type of cam would you use on a supercharged 'street /driver' motor?

And why keep compression low? What do you call low? Is it in relation to the amount of boost?

For what I understand, you would use a low comp. ratio because your forcing more air in. Upping the cylinder pressure like it has more compresion. So you don't start with a high compresion and add more.

A cm with a wider centerline (And it's timing of the events of the blower cam) help trap more of the charge of air and fuel. A narrower centerline cam, like typical 110 centerlines allow the air and fuel to escape since theres more overlap.

A low ratio for these engines I have seen recomended starting at 8.5-1 and lower. I don't know how high of a static ratio you can start with and then add pressure and/or how much pressure.

Okay- new guy here so bear with me. What type of cam would you use on a supercharged 'street /driver' motor?

And why keep compression low? What do you call low? Is it in relation to the amount of boost?

Whoops, my bad, I should've stated static compression. For a street motor, go 8 to 1 or a little lower. On the cam, alot of folks sell "blower cams" that have a huge seperation angle. Try to keep it tighter. Talk to the guys at Hughes or Clay Smith Cams. One of my best friends builds quite a few blower motors and goes on in detail about these things, I am no expert at it myself but the info seems to be sinking in to some level or another. I'm wiring a 38 Chevy for him right now that he just finished a blown big block motor that pulled an honest 800 horse on the dyno. (Trust me, he's been showing me that dyno sheet for a month now.)

[COLOR="Blue"][a blower cam that makes tons of power will be in the 114 center line area,,but it also makes the motor make a lot of added heat,,a 112 center line is streetable,,remember you have to keep it kool a lot of street blower motors over heat all the time,,,, i drive my cat to cruise nites 70 or some times 100 miles away,,last week 103 out my motor never went over 190,,,usually runs 170 around town,,radiator,,and cam,,,/COLOR]

ok i didnt read all the previous hoopla,,

but i do know a little about street blowers,,and before i type a hole bunch of stuff,, ill say this last time ( few weeks ago) same topic,,went back and forth, at the end the person asking the same questions had this to say,,

' ILL HAVE TO SAVE MY PENNIES A WHILE, ITS LIKE 6 TO 8 GRAND TO DO THIS '

read it and read it again,,a average roots style blower motor for the street that is going to start,and run with out coaxing the throttle till the blower builds some heat in it to idle ,,because its costs to much to set the carbs up properly ...

now if you want a complete ready turn key blower motor for the streeet thats affordable go to BIG ALS TOY BOX web site,, he builds all makes,, he is not just a chevy guy,,and that what you are going to find at your local speed/machine shop.,

there are several stand alone items you will need that your not going to find used for a small block mopar,,at your local swap meet,, so gettign a complete set up,with carbs set up properly,,pullys that make every thing line up,, and an intake,, the price of an almost true blower intake alone will make you re think all this,,,

if you decide this is for you and your serious make sure you run a harmonic balancer,,an after market one not a 2 piece factory balancer,, it makes a difference when getting all the pullys worked out,,

i was lucky enough back in the mid 1990s to find my set up used pieces here and there that were all on this motor at one time,,,

i consider my engine almost bullit proof,,was built at an engine shop not a chevy shop,,,my block was re worked X block,, because the orignal owner of this block took it to a chevy speed shop,,and it was butchered, it was a new X block

i took it to a race shop that builds roundy round motors,,they know how to make a motor live,,, they build motors for people like kinser,,,

this motor is a mild street motor and in the mis 90s was 6 grand,including the used parts i was lucky enough to locate,,but didnt enclude blower carbs,,

if 600 HP is what your after easy with a blower,, but also easy with a 360 stroker,,and probably less money,,

if your seriuous ill tel you what ive been able to learn,,about building it properly,,by all meens if you call BDS,,, use your own judgement,,

Jesus fish, what took you so long to get here?

i know sorry,,,it just kept comming out of my head as i typed,,,,sorry,,,just trying to get the point acrossed to do it right even mild,,aint CHEAP ok ill be queit sorrrrryyy

[COLOR="Blue"][a blower cam that makes tons of power will be in the 114 center line area,,but it also makes the motor make a lot of added heat,,a 112 center line is streetable,,remember you have to keep it kool a lot of street blower motors over heat all the time,,,, i drive my cat to cruise nites 70 or some times 100 miles away,,last week 103 out my motor never went over 190,,,usually runs 170 around town,,radiator,,and cam,,,/COLOR]

My amigo Jerry finished up a blown 360 in a 33 Dodge sedan that was an absolute hoot to drive. I can hit him up on the cam specs, but I want to say the centerline was in the 110 range.

i know sorry,,,it just kept comming out of my head as i typed,,,,sorry,,,just trying to get the point acrossed to do it right even mild,,aint CHEAP ok ill be queit sorrrrryyy

No frog no, don't be quiet. You are one of the good peeps who knows what's what.

Besides, I like your car and I get to see it every time you post.....

OH yes, do tell. I'm all ears!

For what I understand, you would use a low comp. ratio because your forcing more air in. Upping the cylinder pressure like it has more compresion. So you don't start with a high compresion and add more.

A low ratio for these engines I have seen recomended starting at 8.5-1 and lower. I don't know how high of a static ratio you can start with and then add pressure and/or how much pressure.

Like most people i didn't filter through the BS in the beginning but I hope this helps.

For comparisons sake, the '94 5.2l magnum in my duster is running the stock rotating assemble about about 10psi with out any problems. The are hyper pistons not forged and about 9.4:1. I know of stock 5.9l magnum rotating assemblies that have been consistently street/track driven at 15psi. Granted these are turbod not S/C'd but the premise is the same.
How much static compression you run will have an opposite effect of how much boost you produce. More compression=less boost and less compression=more boost. There are pros and cons to each.
At a higher compression ration each lb of boost will produce more power than a lb of boost for a lower compression engine. But you're limited to small pressure levels because of risk of detonation
At lower CR though each lb doesn't count for as much you can run much several times more boost than a high CR engine. Obviously the more you compress the air the hotter it will become so cooling the charge will become a large issue as large PSI is reached. Also percentage of power gained per lb will decrease at very high pressures due to flow characteristics and burn efficiencies.

WOW! Thanks! (And sorry for the bullshit)

Very interesting reading. One thing that I haven't seen is opinions on exhaust. It seems to me that standard 1 5/8 inch tubes won't be up to the job for headers and I would want about 3 inch pipes.

Jack

I would think about the projected HP output of the engine and go from there. In example, a mild supercharged build can use a standard header. just like a mild N/A built engine and so on up the HP ladder.

IMO, a tti header would be the best option for a street duty car for ground clearance issues over the 1 size fits all header that has never really worked well in the street for us. There are a few guys useing this header on there every day cars to 10 second runners.
After the header, again, power output should help determin pipe size for the rest of the exhaust.

How much power do you intend on making?

I am thinking somewhere in the 500 to 600 HP range. I can see I am really going to have to research this whole setup. I was doing some reading on a couple of the supercharger sites and a couple of tech sites and the popular belief seems to be that you can start with a stock block. If that is the case I might start with a 5.9 Magnum block. That way I already have a roller cam setup and I would want to use an electric fuel pump anyway.

Jack

I am thinking somewhere in the 500 to 600 HP range. I can see I am really going to have to research this whole setup. I was doing some reading on a couple of the supercharger sites and a couple of tech sites and the popular belief seems to be that you can start with a stock block. If that is the case I might start with a 5.9 Magnum block. That way I already have a roller cam setup and I would want to use an electric fuel pump anyway.

Jack

Research is your best bet, because none of us know what you want as well as you do. With a 5.9l magnum motor 500-600 can be had with a very mild build. It should take about 13psi on the stock rotating assembly with a good tune. I'm bias, but if you're going to an electric fuel pump and a magnum engine anyways I would say go full FI. If its something you elect to do it's very affordable if you use a factor harness and OBD2 comp. The OBD2 computers are readily tunable and have a pretty large following with the dakota/durango crowd. So alot of the ground work is already laid out for you with plenty of help.

I don't mean to hijack, if you have any ?'s about the FI or boost that i can help with PM me any time.

Check Out These Websites:

http://www.thesuperchargerstore.com/products.html

http://www.thesuperchargerstore.com/Kern%20Pressel.html

I think if you're doing a supercharged Magnum with roller cam, you could shoot for more than 500-600 HP.

I think if you're doing a supercharged Magnum with roller cam, you could shoot for more than 500-600 HP.

Why would you suggest that? 500-600 can be very streetable and still maintain good mileage. If someone begins exceeding that it is easy to loose one of both of those desirable qualities for a driven car.

But that can be attained without supercharging it. What I'm saying is, if he's spending the time and money for a supercharger, he might as well go for more. I would think that a supercharged car with over 600HP could be as streetable as a NA car with 500-600, but then again, I've never had any experience with a supercharger, other than on my waverunner, but I'm sure that's totally different.

dont forget about the twinscrewblower they can make a ton of boost without adding alot of heat just like a centrifugal but they still make cracy power down low as a roots,and they have a whine all of there own :)
honestly these are not cheap and there is nothing that can be bought and installed out of a box for them but i think they are the coolest thing around

im shooting initiatily for 8-10pounds of boost on a stockblock 340 with a small solidroller and eddyheads running E85 with 9.7:1compression i may push it upwards 14pounds if i feel a need for it but im pretty sure that will shorten the life of my stockblock seriously

But that can be attained without supercharging it. What I'm saying is, if he's spending the time and money for a supercharger, he might as well go for more. I would think that a supercharged car with over 600HP could be as streetable as a NA car with 500-600, but then again, I've never had any experience with a supercharger, other than on my waverunner, but I'm sure that's totally different.

It can still be streetable above 600, 500-600 if done right will sound nearly stock. If he does elect to go with a stock magnum block they are good to right about 600-700. Thats the neighborhood that block failure is a very real risk. I guess you're right, too me i was thinking budget and said streetability. My college budget can't factor in an R3 block.

I went back and reread nothing was stated about what the car will be used for. Is this gonna be a driver, strip car, or street/strip?

It can still be streetable above 600, 500-600 if done right will sound nearly stock. If he does elect to go with a stock magnum block they are good to right about 600-700. Thats the neighborhood that block failure is a very real risk. I guess you're right, too me i was thinking budget and said streetability. My college budget can't factor in an R3 block.

I went back and reread nothing was stated about what the car will be used for. Is this gonna be a driver, strip car, or street/strip?

Lots more questions to answer and ask. This will primarily be a street car. Probably a 71/72 Demon. I am no different than anybody else, I would like to do it as cheap as possible.
As far as the Magnum setup, I was picking it because it is readily available for cheap. Being able to use the FI and computer would be a bonus as far as street manners are concerned but I am not in the know how to set that up.
The car would be setup to be able to go to the strip but that would be because I can do any of the required fabbing myself. After building my first Demon, my garage is setup pretty good for building another car.

Jack

Check out http://www.turbomustangs.com/ I am in there I have a mild 5.9 with a 62-1 turbonectics in a dakota it went 10.90@123mph on 10#'s I had a procharger dsc-1 I love the turbo alot better but thats just me,get in theere and read the carb section if you want to learn blow through they work just have pacients.

setting up the FI is really quite easy once i got into it. I'd be happy to help with anything you'd need on that.

Thanks TT'74, I may be taking you up on that. Strange as it may sound, I am going to be in your area at the first of next March. My vacation at Cocoa Beach is already booked and we will be flying into Orlando.

Jack

Good deal, should have my duster put back together by then so you can see how everything is set up.

I don't have a ton of blower experience, but I have some. I've built three and helped with one that was a bracket racer. Blowers are expensive. As such, there's something that's never made sense to me. Almost everyone you see running one has it underdriven. This is stupid to me. I've always been of the mindset that if you're gonna spend 5K on one part, use the HOUND out of it. The one blown motor that I built for someone with a free hand was a 340 with a 6-71. We used costom JE pistons at a 6.5 to1 compression ratio and overdrove the blower 5%. He had to run on premium pump fuel, but that thing would really skin it back. This has been about twenty years or so ago. The more you use the blower, the more you can hear it. LOL Also, the volumetric effeciency goes through the roof. Blower motors are all about boost. The more you USE the boost, the better they run. I mean, it just makes no sense to bolt one on and underdrive it. To me, it's pointless. Blown motors also need camshafts with wide lobe separation to help keep cylinder pressure up. You'll need to talk to your camshaft company for the best recommendation for your combination. Lastly, steer clear of those with the teflon rotor seals. They are always giving problems. Going with a 6-71 you probably won't need to worry about that because the teflon seals are usually only in those "mini" blowers that are really only for looks. Hope that helps. If not, just give it a big flush. LMAO

One thing that occurred to me this weekend is that I have been looking at this as building a new car and putting this engine in it because if I was going with a Viper drivetrain or a Hemi, I might as well do that. If I go with a blown smallblock then I can keep my present car and concentrate on the engine only. That would also free up some cash for the engine. There would be other considerations but they would mostly be mechanical related such as radiator and exhaust. This idea is starting to look more feasable all the time. Like I said before, 5.9 Magnum's are plentiful and cheap. They also look like a good base to start on. I could sell my current engine (which is healthy at 400+ HP), to help pay for the blower engine.

Jack

What is your HP goals are you just want to put something together and see what you end up with,I still have the procharger off my Dakota well I sold it to my brother but it is under the bench in the garage it has the brackets for a LA block it was bought from the supercharger store it has two pulleys 8# and a 12#.I'm sure he would let it go he just told me the other day he needs to get read of it.

I don't have a ton of blower experience, but I have some. I've built three and helped with one that was a bracket racer. Blowers are expensive. As such, there's something that's never made sense to me. Almost everyone you see running one has it underdriven. This is stupid to me. I've always been of the mindset that if you're gonna spend 5K on one part, use the HOUND out of it. The one blown motor that I built for someone with a free hand was a 340 with a 6-71. We used costom JE pistons at a 6.5 to1 compression ratio and overdrove the blower 5%. He had to run on premium pump fuel, but that thing would really skin it back. This has been about twenty years or so ago. The more you use the blower, the more you can hear it. LOL Also, the volumetric effeciency goes through the roof. Blower motors are all about boost. The more you USE the boost, the better they run. I mean, it just makes no sense to bolt one on and underdrive it. To me, it's pointless.

You had to run premium on 6.5:1 compression? That must have been some serious boost it was pushing. Not that I can say I really know much about them, but the whole underdrive / overdrive thing has a lot to do with just how much blower you need. I've also heard underdriving is good because it helps keep the air temp down. I was debating this myself as I was waffling between a 6-71 and an 8-71 blower. I could get the same boost from the 8-71 underdriven (with possibly less heat generated from boost than an overdriven 6-71), but I would have to way overdrive the 6-71 if I wanted big boost for a race setup. The big thing is just to check out a blower chart for whatever you go with and figure out what kind of ratio you need. You can really make about whatever you want work if you mess with it. Hopefully I'll have that shiny blower on top of my car next year =P.

Here's my 360 Magnum with a stock short block (except for a Hughes cam), stock heads (very minimal valve bowl cleanup and a 3-angle valve job), a 750 Hollley double pumper and an MSD Boostmaster ignition (boost retard.)

Here's my 360 Magnum with a stock short block (except for a Hughes cam), stock heads (very minimal valve bowl cleanup and a 3-angle valve job), a 750 Hollley double pumper and an MSD Boostmaster ignition (boost retard.)

I tried to upload this chassis dyno sheet for the car, but it didn't make it.

Here's attempt number two....

I tried to upload this chassis dyno sheet for the car, but it didn't make it.

Here's attempt number two....

Not very impressive, for sure, but shows what can be done with a nearly stock engine (stock short block, except for the cam) and almost completely stock heads.

The blower is a Vortech S-Trim, V-1, the compression is stock (OEM) at 9:1 (I checked it), and the redline is 6,000 rpm. I have pulleys on it that give 10 pounds of boost from about 2,500 rpm to the 6-grand redline. I am deathly afraid to run more, due to the cast (stock) pistons....

Headers are TTI 1-58"/1-34" stepped headers, with a 2.5" H-Pipe exhaust system; DynoMax Super Turbo mufflers, and 2.5" tailpipes.

3.55:1 8.75" rear end, 904 T-Flite; 3,340 pounds with no driver aboard.

The 1,000-foot times equate to approximately 11.77 @ 116 mph for the quarter-mile.

Since that run, I have added slicks that are 1" wider (9"), and a 4.10 final drive ratio. The 60-foot times should come down about .3-sec (I HOPE; it was spinning all the way through 1st gear the last time out), so the quarter-mile times should drop into the 11.40s or '50s, I would think. MPH probably won't increase.

I have no idea what its reported 445 rear wheel HP would be at the flywheel.

Too danged hot to race, here, right now...

What is your HP goals are you just want to put something together and see what you end up with,I still have the procharger off my Dakota well I sold it to my brother but it is under the bench in the garage it has the brackets for a LA block it was bought from the supercharger store it has two pulleys 8# and a 12#.I'm sure he would let it go he just told me the other day he needs to get read of it.

Thanks for the offer rdakota340. But I have already had a very generous offer from another member that I turned down. If I do build a blower engine it will be a roots type blower that sticks out of the hood. As I said earlier in the thread I am going for the WOW factor in whichever build I do. I know, it sounds kind of childish, but, I have a pretty quick car right now that is a blast to drive, but I just want something a little different and around here, a roots blower sticking out of the hood is not very common. I only know of 2 in my area, one is a older rod and the other a 68 chevelle.

Jack

Not very impressive, for sure, but shows what can be done with a nearly stock engine (stock short block, except for the cam) and almost completely stock heads.

The blower is a Vortech S-Trim, V-1, the compression is stock (OEM) at 9:1 (I checked it), and the redline is 6,000 rpm. I have pulleys on it that give 10 pounds of boost from about 2,500 rpm to the 6-grand redline. I am deathly afraid to run more, due to the cast (stock) pistons....

Headers are TTI 1-58"/1-34" stepped headers, with a 2.5" H-Pipe exhaust system; DynoMax Super Turbo mufflers, and 2.5" tailpipes.

3.55:1 8.75" rear end, 904 T-Flite; 3,340 pounds with no driver aboard.

The 1,000-foot times equate to approximately 11.77 @ 116 mph for the quarter-mile.

Since that run, I have added slicks that are 1" wider (9"), and a 4.10 final drive ratio. The 60-foot times should come down about .3-sec (I HOPE; it was spinning all the way through 1st gear the last time out), so the quarter-mile times should drop into the 11.40s or '50s, I would think. MPH probably won't increase.

I have no idea what its reported 445 rear wheel HP would be at the flywheel.

Too danged hot to race, here, right now...

Bill,
Those are impressive numbers considering your 60 foot time. I would not doubt that you will get to the very low 11's or maybe high 10's with that setup. You seem to be loosing a lot of time coming off the line and maybe with a little diet in the car could get much quicker. With the rear wheel HP you have I would guess somewhere from 510 to 525 HP at the crank. By the way, that is a really cool sleeper you have there. I bet you surprise a lot of folks with that car.

Jack

You had to run premium on 6.5:1 compression? That must have been some serious boost it was pushing. Not that I can say I really know much about them, but the whole underdrive / overdrive thing has a lot to do with just how much blower you need. I've also heard underdriving is good because it helps keep the air temp down. I was debating this myself as I was waffling between a 6-71 and an 8-71 blower. I could get the same boost from the 8-71 underdriven (with possibly less heat generated from boost than an overdriven 6-71), but I would have to way overdrive the 6-71 if I wanted big boost for a race setup. The big thing is just to check out a blower chart for whatever you go with and figure out what kind of ratio you need. You can really make about whatever you want work if you mess with it. Hopefully I'll have that shiny blower on top of my car next year =P.

We ran around 12PSI if I remember correctly, so premium gas was mandatory. We had no intercooler, as, at the time, they were fairly new technology, so I am sure the air temperature was a factor. Had we run an intercooler, we likely could have overdriven 8 or even 10%, or perhaps run on regular fuel at 5%. For your application, I believe an 8-71 will be a waste. It's all about using a blower to its full potential, especially with a roots blower. The more power that comes from the blower itself, the more efficient the engine will be, as long of course other things are taken into consideration such as the addition of an intercooler. Keeping air temps down, a 6-71 should be enough to boost all but the most serious big block combination.....if done correctly. But remember, I said from the onset i didn't have much blower experience. I'm no expert by any means. I've just dabbled in a few and had success with them, so i thought I'd throw it out there. It's really like anything else. If you use a little common sense, you can really make it work to your advantage.

Thanks for the offer rdakota340. But I have already had a very generous offer from another member that I turned down. If I do build a blower engine it will be a roots type blower that sticks out of the hood. As I said earlier in the thread I am going for the WOW factor in whichever build I do. I know, it sounds kind of childish, but, I have a pretty quick car right now that is a blast to drive, but I just want something a little different and around here, a roots blower sticking out of the hood is not very common. I only know of 2 in my area, one is a older rod and the other a 68 chevelle.

Jack

Nothing stops muscle car folks like a TT set up in a mopar. Just my experience, unfortunately you only get that WOW factor when the hood is up.

For your application, I believe an 8-71 will be a waste. It's all about using a blower to its full potential, especially with a roots blower. The more power that comes from the blower itself, the more efficient the engine will be, as long of course other things are taken into consideration such as the addition of an intercooler. Keeping air temps down, a 6-71 should be enough to boost all but the most serious big block combination.....if done correctly.

Yeah, the main reason I was concerned was I was looking at some BDS blower charts and their small bore 6-71 is just really low boost all around. They report only being able to make around maybe 15 pounds of boost at a max overdrive of 20-30% or something. There was just no way I wanted to run the blower that hard on a high winding small block, it would be screaming at the top end, lol. Their big bore 6-71 was not much different than the 8-71 though, and the Dyer's 6-71 kits I was looking pumped out good boost all the way around. I planned to run around maybe 10 pounds on the street and then pump it up to 15-20 when I took it to the races on race gas.

I will be going on vacation for almost 2 weeks starting in a couple of hours. Keep on posting the info though guy's I will be checking in every 2 or 3 days.

Jack

Not very impressive, for sure, but shows what can be done with a nearly stock engine (stock short block, except for the cam) and almost completely stock heads.

...

that is very impresive performance,especialy considering the almost perfect sleaper looks and from what i would gues a fairly mild sounding exhausttone..
get to work on those 60´s and i think you will easily run low low 11´s may even dip into the 10´s ,getting the 60´s where they realy should be for that performance may take time and alot of patience but i think it would pay of bigtime :)

mid to low 11´s should 60 low 1.5´s from my litle experience on a fairly lightwheigt leafspring streetdriven brand x with a NA smallblock

Yeah, the main reason I was concerned was I was looking at some BDS blower charts and their small bore 6-71 is just really low boost all around. They report only being able to make around maybe 15 pounds of boost at a max overdrive of 20-30% or something. There was just no way I wanted to run the blower that hard on a high winding small block, it would be screaming at the top end, lol. Their big bore 6-71 was not much different than the 8-71 though, and the Dyer's 6-71 kits I was looking pumped out good boost all the way around. I planned to run around maybe 10 pounds on the street and then pump it up to 15-20 when I took it to the races on race gas.

Again, I'm no expert... I cannot say that enough LOL....but remember, what engine the blower is on top of has a LOT to do with available boost, too. A 6-71 on a small block can create MUCH more boost than on a big block. smaller bore, shorter stroke=less room to cram air and fuel into, and that means more PSI. I think those BDS charts are probably just a general guide and not meant to be specific. You can get 10-12 PSI boost real quick with a 6-71 on a small block....THAT, I know from first hand experience.

Yeah, I completely agree, I'm even less of an expert since I've never even driven a blown car, lol. The little charts they had had reference engine sizes and boost numbers for different drive ratios, but I know a lot of that has to do with head flow and other stuff. Never thought about that stroke issue, that's a good point. Besides, a 6-71 is cheaper, lol =P.

I did like the procharger I had but my truck went faster with the turbo on less boost,there is pros and cons on everthing.
YouTube- 94 Turbo Dakota

Thanks for the offer rdakota340. But I have already had a very generous offer from another member that I turned down. If I do build a blower engine it will be a roots type blower that sticks out of the hood. As I said earlier in the thread I am going for the WOW factor in whichever build I do. I know, it sounds kind of childish, but, I have a pretty quick car right now that is a blast to drive, but I just want something a little different and around here, a roots blower sticking out of the hood is not very common. I only know of 2 in my area, one is a older rod and the other a 68 chevelle.

Jack
I like the little 142 blowers they work great for the street,you want the 250 series they stick out of the hood though we have run them they are fun, I just hate having to change pulleys to get more boost and blowers do make power down low too either way you will love boost .

Bill,
Those are impressive numbers considering your 60 foot time. I would not doubt that you will get to the very low 11's or maybe high 10's with that setup. You seem to be loosing a lot of time coming off the line and maybe with a little diet in the car could get much quicker. With the rear wheel HP you have I would guess somewhere from 510 to 525 HP at the crank. By the way, that is a really cool sleeper you have there. I bet you surprise a lot of folks with that car.

Jack

Thanks, Jack, for the kind words!

The day I got that timeslip. it was only 48 degrees and apparently, VHT doesn't work well in cold weather.

My car was spinning HARD, all the way through 1st gear. I tried 6 times; nothing helped.

Since then, I have bought some new slicks that are 9" wide (an inch wider than the old ones) and an inch taller.


I have also installed a 4.10 gear to replace the 3.55 that was in my car when I last ran it.

Better weather will make for some 60-foot improvements, I hope.

Lookin' for some high 1.50s, maybe... :cheers:

that is very impresive performance,especialy considering the almost perfect sleaper looks and from what i would gues a fairly mild sounding exhausttone..
get to work on those 60´s and i think you will easily run low low 11´s may even dip into the 10´s ,getting the 60´s where they realy should be for that performance may take time and alot of patience but i think it would pay off bigtime :)

mid to low 11´s should 60 low 1.5´s from my litle experience on a fairly lightweight leafspring streetdriven brand x with a NA smallblock

Thanks a lot for the kind words!!! I have installed a 4.10 gear and some wider, taller slicks to try to get the 60-foots down about .3.

The day I ran those 1.81's, it was only 48 degrees, and there was just NO bite.... spinning all the way through first gear....

I'll try these new tires, and maybe a little ballast in back... but, not much!!! LOL!

I'll keep you posted!8) Thanks for your interest!!!

Bill

I like the little 142 blowers they work great for the street,you want the 250 series they stick out of the hood though we have run them they are fun, I just hate having to change pulleys to get more boost and blowers do make power down low too either way you will love boost .

Be careful with the smaller ones. They usually use teflon seals on the edges of the rotors and they give problems galore on some of them. I had one get sucked into an engine and we had to go back through the whole thing. I vowed after that, if I ever did another blower, it would be a -71 series of SOME sort. While the teflon sealed rotored blowers can boast about tighter clearances and improved boost, if you ever have teflon seal problems ONE time, you'll be forever chasin your tail. Ask me how I know. LOL Just my 2 cents.

Be careful with the smaller ones. They usually use teflon seals on the edges of the rotors and they give problems galore on some of them. I had one get sucked into an engine and we had to go back through the whole thing. I vowed after that, if I ever did another blower, it would be a -71 series of SOME sort. While the teflon sealed rotored blowers can boast about tighter clearances and improved boost, if you ever have teflon seal problems ONE time, you'll be forever chasin your tail. Ask me how I know. LOL Just my 2 cents.

twinscrews dont have any teflon seals either and they make crazy boost ;) plus they only need one carb and if run fuelinjected im pretty sure they can be low enough to keep everyting under a flat hood,only real downside is that they are pretty expensive and you have to custom fab everyting since there is no manifolds or pulleysetups anywhere to be found out of a catalog, oo wait i just changed my mind i like to custom fab everything since its so rare that anyting that is suposed to be bolt on fits and performs right,right out of the bow anyway ;)

twinscrews dont have any teflon seals either and they make crazy boost ;) plus they only need one carb and if run fuelinjected im pretty sure they can be low enough to keep everyting under a flat hood,only real downside is that they are pretty expensive and you have to custom fab everyting since there is no manifolds or pulleysetups anywhere to be found out of a catalog, oo wait i just changed my mind i like to custom fab everything since its so rare that anyting that is suposed to be bolt on fits and performs right,right out of the bow anyway ;)

Yeah, I've read about them a little. They are supposed to be really efficient. The ones I really like though are the Vortecs. They don't stick outta the hood, but they make gobs of power and torque.

I guess I have not spond one high enough we have not had no problems with teflons coming off are apart but there is a first time for everything they are great for the street.

I have been looking at a few manufacturers of roots type blowers websites. Weiand, Dyers and BDS off the top of my head. The Weiand's seem to be cheaper, but I have been told they are not as good either. The Dyers look like a decent piece and the BDS blowers look like they are very good, but a little pricey. What are your opinions on the different makes?

Jack

remember with pump gas 93 octane will only support 9 lbs of booost with out a computer controlled engine,,

and when choosing a roots type super charger you need to rememeber,these were designed for diesel engines so the formula is this

6 .71 = 6 cylinder x 71 C,I.

8.71 = 8 cylinder x 71 c,.i.

when converting it to a gas engine 6x71 = 426 thats the engine C,I thats the biggest gas engine it will work on making boost and not over heating the engine,,,

all the roots type you see from BDS and such are new offf the shelf units made to be effective on a gas engine,,and made to look show pretty,, but they are also most all of them the small bore case,,

dyer is the guy that started the street super charger movement back in the 1970s,,,but they were converting real GMC super chargers off of diesel engines full size true 6.71 cases,,my dyers blower is a 1965 GMC unit,thats why if you look close it is not as pretty as a off the shelf made for the street eye candy,.,

BDS boost chart is a guide and not 100% accurate,, boost figures depend on real time compression,,not advertised compression,, real compression comes from the piston and chamber size of your heads,,

if you dont have your motor CC ed by your machine shop before assembly your only guessing at what compression you really have,, but you can always put a boost guage on and hammer it,,see if you can read the guage while driving on the street,, no so easy in my car LOL,,,

ive never had a good experience wit hthe people at BDS,, ask 10 questions you will get 20 incorrect answers,,

pick up a copy of street super charging and read it,,you will learn a lot,,

Here is the one I was looking at from Dyers for comparison purposes. It's about 1/3 the way down the page. http://www.dyersblowers.com/1694.html

Polished may not be the way to go unless you are looking at a trailer queen. A lot of cleaning to do there. LOL

I believe I am looking at a 6-71 because I am thinking of a 360 Magnum engine as a base engine. I like that idea as I would already have a roller cam setup and the possibility of fuel injection and computer control. There is also a running 5.7 Hemi available locally for $1000 right now. That would be a one of a kind setup for around here. I have a lot more to learn on this before I start buying anything though.

By the way, I finally got up the nerve to pass this by the wife while I was on vacation. I'm glad to say that she thought it was a cool idea. The trade off was that if I built the blower engine, I would not build another car. I can live with that. LOL The rest of my car was built with more HP and TQ in mind, so I don't have to change much there.

Jack

have you checked,, can you get a magnum blower intake? you may have to get a magnum carb intake and do a plate like an old style dyer intake,,thats what im using,, not on my car but this intake was on annother 340 dyers blower went 10.63 full body all steel 9 inch slick duster,,

I haven't checked for Magnum specific as of yet. They do list a 360 and the 5.7 Hemi but I don't see a 5.9. This is something I will check right away.

Jack

this is a regular 4 bbl intake done by gary dyer in the 1970s,,

as far as i know dyers does not build intakes any longer,, the yuse the hampton intake,,its taller then mine but is still not a tru blower intake,,you may be able to get dyers to build you a magnum intake using a 4bbl inake or use the pics of mine,,and do it ur self,,

Actually, my sister and b-in-law run a truck body fabbing business. They can fab up about anything in aluminum. I bet it would be a lot cheaper than buying an off the shelf intake. That way I would basically be buying the blower and pully setup. Much cheaper than the entire kit.

Jack

well if he can weld aluminum ide do it that way,, just get a carb intake for the magnum 296 bucks at summit,,, and cut a plate ,,then justy build a few stand offs like on mine to support the plate,, if some oen makes but i doubt,,get a dual quad inline intake and built it that way,,, on the early intake like mine the thermostat housing is the only problem,,like it or not,,, the GM t housing is the same bolt patteren as the mopar,,but the thermostat is a different diameter,,,

and mopar and gm are oppisite,,gm the t stat is sunk in the intake mopar the t stat is in the housing,,, 2 ways to over come this is,,,

have your intake cut to accept the gm t stat,,, or like i did,, i bought a new iron gm t housing and had that machined to accept the mopar larger thermostat,,,and i used thermostat housing sealant,,

the better way would be machining the intake to accept the thermostat like a chevy intake,,,

I now somebody makes an inline dual quad for a magnum as I have seen one. Now just to track down the owner of that car. I was wondering about the squeeze on that single 4-barrel intake as that would raise the temp of the air going in.

Jack

well u may be right but i have NO temp porblems, i drive all over to cruise nites, in traffic,,interstate,,in the cold season and 100 degree weather,, 6% under driven making 13 pounds of boost on 93 pump gas,, a factory style radiator 4 row 22in x 19 in A body/ dodge van radiator
cruises at 178 degrees on the interstate last week in 101 degree temps out side i was at 195 in trafic,, using a mechanical fan,,

Indy have a blower manifold now for those of you intrested in it, both for LA heads and Magnum heads :) its in there modman series that can be used with 1 or 2 fourbarrels or even a sixpack they also have an adaptorplate to make it work with a blower :)

nice didnt know they had them for an LA or MAGNUM,, only knew about there modman for the new hemi,but knowing indy,,,,you will need a loan to get one ,,,thanks for the info

Yes thanks for the info.

I have a email into Dyers on weather or not they have a kit for a Magnum.

In the meantime I came across this intake for a 273/318. If you redrilled the Magnum heads to accept the bolt pattern would it work? http://www.summitracing.com/parts/OFY-5615/

Jack

Yes thanks for the info.

I have a email into Dyers on weather or not they have a kit for a Magnum.

In the meantime I came across this intake for a 273/318. If you redrilled the Magnum heads to accept the bolt pattern would it work? http://www.summitracing.com/parts/OFY-5615/

Jack

see if there is one listed for the 340 may have larger ports,,offy still makes any thing u want, they still have all there old molds,,no web site from what ive been told,,and they had one for a 340

I heard back from Dyers, they don't make one. I checked out the Indy Modman and it is $694.00, not a bad price for Indy.

Jack

no not a bad price at all even for indy,, i called them last week,,,just to see,,and the price the ygave me on a mod man 5.7 single 4bbl intake seemed way to cheap, 399.00 im now guessing that didnt include the top.,

if you bought a standard small block blower intake from hampton,,,they are like 1200 bucks,,,,so the mod man will do the job for you i assume,,,,

I have done some checking around. The stock 5.9 magnum is a good platform to start with strength wise. The block is plenty strong to take 600 HP. Indy makes an intake that will bolt right on for $634. I am having problems trying to find a piston though. I would like something to bring the CR down to 7.5 to 8.0 to 1 static with the 58 cc heads. A cam shouldn't be a problem, a roller with about .510 total lift and 235 duration @50 and a 112 centerline should be the ticket. Carbs seem to be about anything I want to put on top. All the way from 2 450 Edelbrocks up to a couple of Thermoquads seem to work. More investigation needed there. I don't know if my current exhaust will work or not. I have 1 5/8 primary's to 3 in collectors to 2 1/2 inch mandrel bent pipes and flowmaster 40's with a x-pipe.

Jack

you will probably have to have the pistons made,,if you do get 10 2 extra,,,so you dont have to pay a bundle to get one if some thing happens..

you can go as high as 8.5, compression ,just slow the blower down,, my compresssion is actuall 7.76 arias pistons,,,

as for a carb,,this is critical,,,look at hollys blower ready carbs, it makes a ton of difference,, i have 2 regular 650s,,,i always had to wait for the blower to build heat before it would idel,,,and othere small problems,,

sent the carbs to a guy that does blower carb,,,950 bucks later,,,turn the key,,and smoth as silk,,,,now these carbs flow 862 cfm each,,and tuned for 93 octane and street driving,,

have you had a look at runing on E85? that way you can run alitle more compresion and it will also run alitle cooler from what i have been told, but its not a very good moneysaver since the fuelsystem will eat the savings and some more pretty quick:(

E85 is not readily available around here. I don't think I have ever seen a pump for it.

Jack

If you get a magnum I personally wouldn't mess with the rotating assembly. I know of several people running the stock bottom end in the 15ish psi range no problem. A 5.9l at 15psi with good heads, intake, cam will put you way past the 600 range. On the magnum engines with FI the stock block is the weak point long before the rotating assembly assuming it's tuned properly.

hey Jack....

Dont mean to hijack.....but you should really consider all your forced induction options.

A Single Turbo Small Block would be streetable, yet viscous on demand.
Just Imagine this, with a Mopar LongBlock:
http://i40.photobucket.com/albums/e237/kpgsx/V8singleturbo.jpg

Vs.

http://i40.photobucket.com/albums/e237/kpgsx/Supercharged360.jpg



I respect cubic dollars either way.
I will Butt Out now.
Prine

I have an Offenhauser circle 360 intake but it looks slightly different from yours center divider is notched was yours built up for some reason?

I looked at the photos better and see that the divider runs right through.

I didn't read through all this but there seems to be a lot of misleading and completely ridiculous info being posted. Take it from those that have built supercharged street cars and ask everyone you can and do your homework before you spend one penny on a blower and don't take short cuts to save a buck because it will cost you $100 for every buck you try to save.

Don (fstfish66) knows what he's talking about and I did see a few other helpful comments but if someone tells you that you can run 15+ pounds of boost with a roots blower on pump gas, they're full of it. I'm running 8.5 compression pistons and my blower is over driven 3% making almost 7 pounds of boost and my final compression is 12.4-1 which is MAX for pump gas. If I had a lower comp piston I could bump the boost up some but the amount of boost is calculated by your comp, cubic inches and the amount of drive you're running and each engine is different. You want to keep the final compression under 12.5-1 no matter what your combination is.

As far as heads, they make a huge difference with how the engine will run, as mentioned above the blower is forcing air down the intake and if the heads don't want to flow, you will have nothing but heating issues. Get yourself a good set of aluminum heads and port them, the aluminum cuts down on the heat and a good port job will make them flow.

You definitely want to go with a good pair of blower carbs, I'm running a pair of 750 Demon blower carbs and they ran perfect right out of the box. They are a little pricey at $550 each but they were well worth it.

Unless your running practically no boost at all, DON'T run a stock lower end, that's a short cut you will regret. You need a good set of forged pistons as well as a good set of rods and a forged crank. A girdle would also be a big plus if your wanting to run any kind of power.

Dyers and BDS are both good companies, Weiand don't make anything for a small block Mopar. I found though that a lot of the boost numbers Dyers has posted is off from every other boost chart I found in books and online so keep that in mind when making your decisions.

You will also find that out of 20 people experienced with roots blowers you ask, you will get at least 20 different ways of doing the same thing so ask everyone you can and read as many books on supercharging that you can and it will get a lot easier to make the right decisions. A couple good books I found were Street Supercharging by Pat Ganahl and Super Power a do it yourself guide to turbocharging, supercharging, fuel-injection & nitrous-oxide.

Kelly, always feel free to jump in with your opinion. I know you are big on turbos,but you knowledge on boosting engines is invaluable.

Jack

Blownfish, that is some of the best advice that has been presented yet. I am taking all of the info in and will get some of the books that are being mentioned throughout this thread. Like I have said, I don't want to spend any more than I have to, but I won't cheap out either.

Jack

The essentials for Boost are the same across the board for internal combustion engines.

Low Compression CR (below 9:1 static CR)
MLS Head Gasket(s)
O-rings cut into the head, for sustained boost over 30 psi
ARP Head Studs/Bolts
Forged Pistons with loose ring gaps (.019"/.022")
Forged H Beam Rods
Forged Crankshaft
HV Oil Pump
Copper Spark Plugs

Adequate fuel system....proper octane.

Heat is your enemy.

I would also like to add that with a turbocharger system....changing your boost level is as easy as turning a door knob.....really:
http://i40.photobucket.com/albums/e237/kpgsx/incarboostcontrol.jpg

and that going from 6 psi with a roots blower to 8-10 psi requires:
http://i40.photobucket.com/albums/e237/kpgsx/beltconfig.png

my .02 :read2:

Kelly,

I read your post above on what is required for 30 psi. I was wondering what you think would be needed for parts with boost in the 10 to 12 lb range with a compression ratio of 8 to 1 static.

Now, off to look for the book called "Street Supercharging".

Jack

I managed to find the book "Street Supercharging" by Pat Gandahl. Not a bad price either. $24 shipped to my door.

Jack

I was looking on Racing Junk and came across this ad. I don't plan on buying it, but was wonder if you thought it was a decent deal?

http://www.racingjunk.com/category/1275/Blowers/post/1919920/POLISHED-MERT-LITTLEFIELD-BLOWER-AND-KIT.html

Jack

10-12pounds is alot if you are doing it on the street, i have not done alot of work on blown engines myself more than that i am in the proces of building my own first blown engine but i can tell you that i have a friend with a 383 #¤%&&smallblock with a pretty big blower cam and alitle under 8:1compresion and that thing wont take more than about 7 pounds of boost on pumpgas since the blower makes so much heat.. at 7pounds that 383 made a very real 600hp and the torque is fully capable of basicly blowing the tires of from under the car at 60mph,thats called torque in excess....
i would read anything blownfsh writes carefully he knows alot about this and there is no replacement for a rocksollid shortblock when it comes to blown engines

I have been talking to Dyer's. They recommend a 6-71 with 6 to 8 lbs of boost with an 8 to 1 compression ratio. Anything over that and they believe I will get into heat issues. They also can sell me a kit which includes all polished items for less than $3000 as long as I supply the intake and ship it to them to make sure all is going to work. Sounds like a decent deal to me for all new components. I would still have to buy the carbs and fuel system which adds up quick.

Jack

yep it all adds up very quick,its almost like the blower and manifold is the cheap parts when the whole picture is seen...
i got a billet intakemanifold being made by a small local machineshop and it sure isnt cheap but seeing the big picture i dont care anymore about what the cost is for a large part

The essentials for Boost are the same across the board for internal combustion engines.

Low Compression CR (below 9:1 static CR)
MLS Head Gasket(s)
O-rings cut into the head, for sustained boost over 30 psi
ARP Head Studs/Bolts
Forged Pistons with loose ring gaps (.019"/.022")
Forged H Beam Rods
Forged Crankshaft
HV Oil Pump
Copper Spark Plugs

Adequate fuel system....proper octane.

Heat is your enemy.

On a single Turbo SBM application to get around 700-800 Rwhp, what size turbo would it require and what exact set up would you use etc?

Would it need to be Intercooled?

Same question with Dual Turbo's?

This would be on a STROKED 410 CI Small Block!

I started reading the "Street Supercharging" book today. I'm about 1/3 the way throught it. I think my head is going to explode. LOL

Jack

There was a magazine engine build not too long ago. I think it was a mopar action, Oct 2010. They used a very low dollar almost stock 360 with smog heads and 1.88 valves. The result was about 400 h.p and over 450 ft/lbs tq!

They simply bolted on a paxton kit ($3500) and a mighty demon 750 that was built for blow through. The cam was a small comp extreme energy .462/.470 lift 262/270 duration so very good street manners.Crane adjustable rockers were the only other non stock part.

Federal mogul forged pistons and eagle rods were thrown in too but they dont make more power,just help durability.

Hey Guys
I just picked up a 72 demon with a 340 and a 471 blower. First blower i have ever had so i'm a little on the paranoid side of it all right now. I have driven it a few times now and my temp gets up to 190 sometimes even 200 but then i get scared and pull over. Then i keep the waterpump running and the fan to cool it down. Now does this all sound way to hot to you guys?

My duster has always ran cool as a cucumber never over 170..

I'm not sure of the boost in the demon as the guy i bought it from wasn't sure of how much, there is a vacume gage in the car so is there a way to figure out the boost that way or do you have to measure the bottom and top pulley?

Its the same kind of problem with my Lil Red and my 4X4 they all seem to get up to 190 or so too which seems hot to me.

I cooked a 360 once so now i'm really paranoid on temps.

Here is some of the info on the motor set up.
9:1 compression
Solid lifter setup
Forged Pistons
J heads heavily ported, stainless steel valves, single groove retainers .600 lift
Aluminum 1.5 ratio roller rockers
Aluminum hold down blocks on the rocker shafts
Hardened push rods
Steel crankshaft, balanced assembly
750 Holley
727 trans with 3500 stall
5:13 rearend
aluminum be cool rad, electric fan, electric motor for water pump

So if anyone has any idea's for me to keep it cool, that would be great.
Thanks
Jason

The magazine blower project engine was only a 318 and made that much power. It just goes to show what forced induction can do for you.

the motor in the magazine was a 360 motor with what they called the worst small block mopar heads,,,if i were paxton i wouldnt of wanted that artice to come out for almost 4 grand in parts,,not including if u paid some one to install it it only made 60 more horse power,,,blowers commonly make 45 to 50 % more power,,, 4 grand for 60 hp ??? you can get that with a good cam selection and heads,,for a lot less,,,


demon 340 with a 4.71?? are you sure its a 4.71 ??? and not a 144 or 177 under the hood blower ??? if its truly a 4.71 that blower is too small to make power with out being pushed so hard it wil make a ton of heat,,,,

4 x 71 = 284 cubic inch,,any thing bigger and its just a hot piece of eye candy,,,lets see a pic of the blower and motor,,,a good fan in the proper location,and 4 row radiator will keep it kool,,or a big 2 row aluminum radiator,,


i run a standard factory style radiator 4 row with a water pump mounted fan,,7/8 of an inch fro mfan blade to radiator,,,178 temps all day long and when its 102 degrees out its about 181 degrees,,,

Well the guy i bought it from said thats what it was. I'm not really sure how to tell the 471/671/871's apart. Here is a pic though.. Let me know what you think. The old rad is gone and a aluminum becool one is in now..

[COLOR="Blue"]ok hard to tell from that pic,,doesnt look likea 4.71 but looks smaller then a 6.71,,, measure it from front to back,,,but not the snout,,,the snout is the long front piece with the upper pully on the end,,, just measure from front case to rear and ill compare to mine OLOR]

Been tossing around the idea of a blown big block. Am I correct in assuming that if I were to run efi it will need injectors above and below the blower, assuming it is a roots style?

Been tossing around the idea of a blown big block. Am I correct in assuming that if I were to run efi it will need injectors above and below the blower, assuming it is a roots style?

Use a 400 block Doug. The 440 mains tend to crack with blower abuse.

Hey Fstfish
Just measured the blower. From front to back its measure's length 14.5", height is 7.5", Width is 11.25...