Experts and Know-it-alls welcome..

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nodemon

nodemon

FABO Gold Member
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Greenhorn here..wet behind the ears...etc...but trying to learn as much as possible..
So, based on posts and opinions on this site, I have purchased an Edelbrock LD4B intake for my 73 318 block. Also, topping it with an Edelbrock 1406 carb..fresh and ready. The 73 engine that's sitting in my 72 Demon has mismatched heads.. One 675 cast 318 head and a 1967 273 head..maybe it works, maybe not...have not tried firing it up since purchased in January. ( does turn over by hand ..fingers crossed ). So again, based on some suggestions I just bought a set of 302 casting heads... These heads were gone though and seals, seats replaced...valve job etc.. though it was done 10 plus years ago and they've been sitting ever since.. Sprayed?? ( whatever that means ) and wrapped in plastic.. They look extremely clean and fresh to me.. Paid $500 for them...and he threw in a Mopar brand engine gasket kit..lol
Anyway, these don't have rocker assemblies.. Can I just use the ones off my 318 and 273 heads that came on my engine..? Should I buy new..find a set on here that someone may have..? And, this guy mentioned something about maybe needing different length pushrods..
I'd like to put in a MILD cam.. To be honest, I'm not really going for hp, just want something a little lumpy..love the sound..! Recommendations on cam that I wouldn't have to change anything else to get the lumpyness... 318, 3spd manual w/ 3.23
A lot written here, I apologize..but just wanting some help. Thanks..!!
 
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Anyway, these don't have rocker assemblies.. Can I just use the ones off my 318 and 273 heads that came on my engine..? Should I buy new. And, this guy mentioned something about maybe needing different length pushrods..
alot written here, I apologize.
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yes you can use the 273/318 ones (assuming the 273 is a hyd lifter cam). no opinion if new is needed. on mockup check the lifter preload to find out if you need different pushrods & go from there. I wouldn't think you would need custom lengths but if so watch the straub industries utube vid on "rocker arm geometry". No apologies needed, we are here to help & be helped! (I learn every day I am on here). the treasure trove of info that the guys here posess is off the charts. RR
 
a couple things. "sprayed" probably means with some kind of light oil to keep from rusting. do you know if the heads were shaved at all? if they had enough taken off of them you're going to want to have some taken off the intake to match. i would have a machine shop go over the heads. make sure the valves don't leak, check the valve springs (unless you're going to get a "cam kit" w/ lifters and springs, i would. you will need to mock up the motor and see if there's any mis-match at the port faces. you should be able to re-use the rockers and shafts, but inspect for wear and post some pics to get a second opinion. pushrods are going to depend on what you find during mock up.
a lot of others here can help with checking push rod length
 
kursplat said:
a couple things. "sprayed" probably means with some kind of light oil to keep from rusting. do you know if the heads were shaved at all? if they had enough taken off of them you're going to want to have some taken off the intake to match. i would have a machine shop go over the heads. make sure the valves don't leak, check the valve springs (unless you're going to get a "cam kit" w/ lifters and springs, i would. you will need to mock up the motor and see if there's any mis-match at the port faces. you should be able to re-use the rockers and shafts, but inspect for wear and post some pics to get a second opinion. pushrods are going to depend on what you find during mock up.
a lot of others here can help with checking push rod length
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Not sure about details on what was done on heads, other than what I mentioned. Why would I need anything taken off the intake..? Intake is for 318..
 
nodemon said:
Why would I need anything taken off the intake..? Intake is for 318..
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IF the heads had the combustion side cleaned up to make them flat, or the chambers smaller to raise the compression, the face the intake bolts to may not be at the same angle, so the face of the intake may not lay flat against it. you'll find out the hard way when it sucks oil into the intake and cylinders
 
Good choice for heads. A good cam would be Hughesengines. Com 318 whiplash cam. Go to their website and view the videos of cars running the cam. Sounds damn near like a funny car and performs well. They also have a tech article on intake manifold fitting and sealing. I would buy the cam kit with lifters. But not the adjustable rocker arms. Use the stamped steel stock ones, used,new or what you got. Grind bananna grooves in the bottom of the shafts across the oil hole where the inside bottom of the rocker arms ride. Make sure shafts are installed right side up facing the right direction. Take pictures of the before you disassemble them off your old heads, mark rocker arm order so arms go back on the shaft the order they were on. Those guy at Hughes engines will try to sell you everything under the sun, especially Dave Hughes. Buy just what you want. They talk a good game, but also their parts are cutting edge and top quality.
 
Hughes Whiplash cam for the 318. Made for stock valve springs and will sound lumpy.
 
nodemon said:
I'd like to put in a MILD cam.. To be honest, I'm not really going for hp, just want something a little lumpy..love the sound..! Recommendations on cam that I wouldn't have to change anything else to get the lumpyness... 318, 3spd manual w/ 3.23
Click to expand...
Before you do anything
to your 1973 318 shortblock,
I highly recommend that you figure out what the final assembled compression ratio will be.
And figure out exactly which transmission you have and the ratios.

To run an A230 (ratios of 3.08-1.70-1.00), with a 3.23 rear gear, your engine will need a good amount of low-rpm and midrange torque. A lumpy cam will destroy the bottom end of an 8/1 engine.
Even the whiplash will start out very soft from idle, picking up as the Rs rise, and finally at about 2000 to 2200 when it starts acting normal.
Yes that Whiplash cam will work in an 8/1 engine; but it needs an automatic transmission with a 2000 or better stall. Which means that in that combo, the engine will never have to pull below 2000, and the Rs will spool up fast enough to cover the what little hole might be left.

But the manual trans does not have that option.
As a lo-po streeter, you will be spending a lot of time below 2000rpm. With 3.23s, and 26" tires, 2000 comes at 16 mph in first. but not until 28 in second/48 in third.
So on a typical drive around town, you might take First gear to 2800/ 22mph then shift into Second. The Rs will fall to 1550 and there you are stuck in la-la land until over 2000/28mph .
When merging onto a hiway, you soldier on, hitting 2800@40 mph, then shift into Third. The Rs fall to 1660 and there you are again in soft-zone. From there,it's a long way to 2000=48mph. Then the power will pick up on the way to 65=2700
Because of the hole caused by the lumpy Whiplash cam, you will tend to avoid that hole by reving the engine higher. To drop into Second at 2200, you would need to rev First out to 4000/31mph.
Think about it.
To run with that combo of Whiplash/3.23s/wide-ratio manual trans, your 318 needs a lotta cylinder pressure, and the only way to get it with that cam, is to pump up the static compression ratio. And then you may run into problems with too much pressure after say 2600/3000.

FABO has seen several guys complain about exactly this, even with automatics; and one automatic guy finally pulled it out.
If you have to run that cam, install an automatic, and run a 2600TC, at least. Hughes makes several stipulations; the first of which says;

WARNING: Our Whiplash cam is designed for basically stock, low compression engines. This cam will run on pump gas in a 318 with 8.6:1 or less compression and iron heads. If your compression is higher than this you may need to use a higher octane race fuel. Your vacuum should be in the 9"-11" range using this cam.
(Figures calculated using stock stroke & compression at 750' altitude.)

Note-1; WIKI says you are closer to 480ft elevation.
Note-2; pay very careful attention to how Hughes has worded this warning. They go straight to race gas after 8.6

click on the link;
Hughes Engines
 
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AJ/FormS said:
Before you do anything
to your 1973 318 shortblock,
I highly recommend that you figure out what the final assembled compression ratio will be.
And figure out exactly which transmission you have and the ratios.

To run an A230 (ratios of 3.08-1.70-1.00), with a 3.23 rear gear, your engine will need a good amount of low-rpm and midrange torque. A lumpy cam will destroy the bottom end of an 8/1 engine.
Even the whiplash will start out very soft from idle, picking up as the Rs rise, and finally at about 2000 to 2200 when it starts acting normal.
Yes that Whiplash cam will work in an 8/1 engine; but it needs an automatic transmission with a 2000 or better stall. Which means that in that combo, the engine will never have to pull below 2000, and the Rs will spool up fast enough to cover the what little hole might be left.

But the manual trans does not have that option.
As a lo-po streeter, you will be spending a lot of time below 2000rpm. With 3.23s, and 26" tires, 2000 comes at 16 mph in first. but not until 28 in second/48 in third.
So on a typical drive around town, you might take First gear to 2800/ 22mph then shift into Second. The Rs will fall to 1550 and there you are stuck in la-la land until over 2000/28mph .
When merging onto a hiway, you soldier on, hitting 2800@40 mph, then shift into Third. The Rs fall to 1660 and there you are again in soft-zone. From there,it's a long way to 2000=48mph. Then the power will pick up on the way to 65=2700
Because of the hole caused by the lumpy Whiplash cam, you will tend to avoid that hole by reving the engine higher. To drop into Second at 2200, you would need to rev First out to 4000/31mph.
Think about it.
To run with that combo of Whiplash/3.23s/wide-ratio manual trans, your 318 needs a lotta cylinder pressure, and the only way to get it with that cam, is to pump up the static compression ratio. And then you may run into problems with too much pressure after say 2600/3000.

FABO has seen several guys complain about exactly this, even with automatics; and one automatic guy finally pulled it out.
If you have to run that cam, install an automatic, and run a 2600TC, at least. Hughes makes several stipulations; the first of which says;

WARNING: Our Whiplash cam is designed for basically stock, low compression engines. This cam will run on pump gas in a 318 with 8.6:1 or less compression and iron heads. If your compression is higher than this you may need to use a higher octane race fuel. Your vacuum should be in the 9"-11" range using this cam.
(Figures calculated using stock stroke & compression at 750' altitude.)

Note-1; WIKI says you are closer to 480ft elevation.
Note-2; pay very careful attention to how Hughes has worded this warning. They go straight to race gas after 8.6

click on the link;
Hughes Engines
Click to expand...
Firstly, thanks for taking the time to respond..much appreciated..!!
Secondly, Daaaaaaamn....that may be the most detailed, thourough explanation I've read.. !
Thirdly, Unfortunately, I'm not sure what a lot of that means, but for some reason makes sense...and even though I'm a bit unsure on some of that, I think it's basically saying to stay with the stock cam with the drivetrain I have...or convert to automatic. Ironically, maybe, that's what I wanted to do when I first bought this car.. A buddy of mine even gave me a sweet console. I decided I'd at least for now, a pedal car would be fun..not to mention, I bought a pistol grip to top off that 3spd.. : )
So again, thanks for an awesome response.
 
Just stick the Whiplash cam a few more degrees advanced from the cam card. That'll solve any "softness" on the bottom end. Trust me, it's a good upgrade to an otherwise stock 318. That's what it is MADE FOR.
 
RustyRatRod said:
Just stick the Whiplash cam a few more degrees advanced from the cam card. That'll solve any "softness" on the bottom end. Trust me, it's a good upgrade to an otherwise stock 318. That's what it is MADE FOR.
Click to expand...
That's what makes this forum so cool...and confusing..lol. Now see, I like your response better, because I get the cam.. What's that mean to set it a few more degrees advanced..?
 
nodemon said:
That's what makes this forum so cool...and confusing..lol. Now see, I like your response better, because I get the cam.. What's that mean to set it a few more degrees advanced..?
Click to expand...
Well...this might be a little confusing at first, but it's "need to know" for doing engine stuff, so here goes..
Camshafts are ground with a certain Lobe Separation Angle (LSA). Let's use 110° as an example here. Now, your cam card may say something like "these specs are for an installed centerline of 106°..."
That means they're having you install it 4 degrees advanced (or they may say their cam "has 4° of advance ground into it"--same difference.) It *should* then match the valve timing events shown on the card.
But, that doesn't mean you can't advance it a few more degrees (this is what RRR is saying)..so you could install it at 104° for a total of 6° advanced, or even 102°...you get the idea. Generally speaking, advancing the cam moves the power band down (helps bottom end) and retarding the cam moves the power band up.
It's done during the cam degreeing process...so if you haven't done that before, start researching or find a buddy/shop that can help you. Some guys just "stab it and go" but there are many reasons to degree or 'verify' the cam so for me it's not optional..
 
nodemon said:
That's what makes this forum so cool...and confusing..lol. Now see, I like your response better, because I get the cam.. What's that mean to set it a few more degrees advanced..?
Click to expand...

The camshaft has a lobe separation center line. I don't know what it is, I'm too lazy to look it up....so for the sake of conversation, let's just "say" it's 108*. Most cam cards say to install cams 4* advanced. That would be 104* intake center line FROM the 108 lobe center. Some say 5*.....but "whatever" let's just say it says 104* for the sake of argument. That's 4* advanced. You could probably go down around 100* but I think I would stop at 102*. With a lower compression engine, advancing the camshaft picks up cylinder pressure and pumps up bottom end torque at the expense in a VERY small reduction of top end torque.

Conversely though, Retarding the camshaft timing takes away a good bit from the bottom end while adding a very small amount to the top. Usually, advancing is the way most people want to go. Unless you're roundy round racing and trying to cut down on traction loss coming out of turns and that kinda thing.
 
I’m not with AJ on shift points. IMO, he makes a mountain out of a mole hill. But the numbers expressed so have merit. I just don’t see winding up the engine to 4K to shift because of the cam and gear ratio spread.

His slow driving shifts are to low. I’ve driven this transmission in a Duster before w/3.23’s with a stock 318. You do rev higher than a closer ratio trans, but not 4K.

IF! You go the whiplash route, or what ever cam you use, take not to how low the rpm drops and then adjust accordingly on the rpm before shift.

Also the description in lack of power due to the low rpm has merit, but again, I’m not sure “La-La land fits the bill!
 
318 & 3.23 axle. Requires careful consideration in cam selection, because a poor choice could render performance to canine status. Someone mentioned 10-11" of vac for the W cam. I presume a lot of that comes from the extra exh duration, which gives the engine the raspy exh sound [ hey, girls look at me! ], but kills low end tq. The last thing you would want to do with a small engine such as 318 & 3.23 gears is kill what little low end it has.
A much better cam in my opinion would be the Isky 264 Mega cam. It is a single pattern [ same duration, int & exh ], will have a 'noticable' idle, with broad off idle power range in a 318.
 
Bewy said:
318 & 3.23 axle. Requires careful consideration in cam selection, because a poor choice could render performance to canine status. Someone mentioned 10-11" of vac for the W cam. I presume a lot of that comes from the extra exh duration, which gives the engine the raspy exh sound [ hey, girls look at me! ], but kills low end tq. The last thing you would want to do with a small engine such as 318 & 3.23 gears is kill what little low end it has.
A much better cam in my opinion would be the Isky 264 Mega cam. It is a single pattern [ same duration, int & exh ], will have a 'noticable' idle, with broad off idle power range in a 318.
Click to expand...

I was thinking of a single pattern cam. I started looking around but called it quits and went to bed. Just simply ran out of gas… LOL
 
First and foremost now that you've heard all the know-it-alls LOL now the expert opinion.. BAHAHA...
I know most want the world and want it now so you went ahead and bought what you thought was good but my expert opinion would have told you to wait 3 months till Speedmaster has their Black Friday sale and have a brand new set of aluminum heads sent to your front door completely loaded with springs and valves for $700...
And quite honestly I would have ran the mismatched heads and seen what happened first before I went and spent my money on some 10-year-old used heads...
In the end I don't see anything you're doing wrong as a matter of fact you're doing everything right you're enjoying your hobby... Remember because that carburetor is new in a box doesn't mean it is adjusted correctly... Don't let that simple carburetor be a mystery to you.. read the instructions and tuning manual twice as the first time you'll go over it going blah blah blah in your brain and then the second time you might actually retain some stuff that'll help you and don't forget to refer back to it as well..
Now you've heard from the expert it's time to enjoy... LOL..
 
What A/J is saying is that if your driving this car casually you will give up that seat of the pants exceleration for a raspy sounding exhaust note. It is good advice ! Many guys build an engine for a high horsepower number and then are disappointed in the prrformance because they dont drive aggressively . If you build the engine with tons of low end torque you will smile every time you shift ! If you build it for a nasty sound you will only be happy at idle or 4500 rpms. When was the last time you hit 4500 ? If you drive like that then build the engine accordingly . I drive my Barracuda every day and find in reality I seldom ever hit 3000 rpm unless cruising the freeway at 75. But I am running 2.76 gears right now because of freeway speeds around here... I have some 3.23s I need to finish setting up.
 
mbaird said:
What A/J is saying is that if your driving this car casually you will give up that seat of the pants exceleration for a raspy sounding exhaust note. It is good advice ! Many guys build an engine for a high horsepower number and then are disappointed in the prrformance because they dont drive aggressively . If you build the engine with tons of low end torque hou will smile every time you shift ! If you build it for a nasty sound you will only be happy at idle or 4500 rpms. When was the last time you hit 4500 ? If you drive like that then build the engine accordingly . I drive my Barracuda every day and find in reality I seldom ever hit 3000 rpm unless cruising the freeway at 75. But I am running 2.76 gears right now because of freeway speeds around here... I have some 3.23s I need to finish setting up.
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Wait a minute there's still people reading all that crap that aj repost... LOL..
 
AKA - Choose a cam with your cruise rpm in mind.
As with the OD-A-833 & most 3 spd transmissions, the gear ratios are not perfect for a lot of things.

The most annoying gear shift is 1-2.

Also love the comment of people building hot rods but yet drive them like grandma. How true.
 
now that you're totally messed up i'll add my 2 cents.
Just install a stock 360 2 barrel cam at about .410 lift, have fun and burn some rubber
 
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