Swapping in a big block

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72chargerguy

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Well, I sold my 72 charger and picked up a 74 scamp. I have a 650 hp 383 I want to drop in. Anything special I need to make this happen? I have a 727 being built for it, and I will be running a ladder bar set up with 10" slicks. Think the stock rear will handle it?
 
One thing to remember when dropping a big block in an A-body is you need to consider the car as a whole package with upgrades to the suspension, brakes,cooling, etc. to insure the cars integrity and safety.
 
Putting A big block into an A body is a big step up from when it was first engineered, mostly the increased weight in the front of the car and the increased torque you are going to subject the unibody too. Like Longgone said, consider the car as a whole package.

I'm planning on dropping a 400 and 727 into my Duster but before I do I'm making improvements in the other areas first such as BB radiator, 8.75 rear end with rear discs, frame connectors etc. I'n not worried about the torsion bars because i'm just racing the car right now but if you plan on driving on public streets you might want the bigger torsion bars that are used in the big block cars before bouncing over to many speed bumps. :read2:
 
i've got slant 6 torsion bars with 440 engine in my 1970 dart & i drive the car everday.....
Picture630-1.jpg
 
My scamp has the original 318 in it, it currently runs and drives. I really don't think I need rear discs on this car. I will run rear discs if I run an aftermarket rear, but if I can keep the stock rear. I just got the car today, I am not sure what rear is under it, I have not hada a chance to look. I have a set of ChassisWorks ladder bars and a S&W 10-point cage. The motor is a 383, std bore, 12.5 pistons, Eagle forged H-beam rods, ported and polished 906 heads, lunati valvetrain, it should be between 650 and 700 hp before the spray. The 727 is being built to hold the power. I am in the process of ordering an aluminum radiator. This is a drag-strip only car, I am going to strip the interior, gut everything and make it as light as possible. I am shooting for a low 10-sec ride. The cage will add some real stability to the chassis, the ladder bars will be tied to the rear attachment points of the cage. I just need to know what I need in the way of motor mounts. I had a 72 charger for this build, but I decided it was too rough to build and too heavy. I also didn't like the way it looked. I like the Scamp, it is unique enough that it will fly under the radar. So what do you think?
 
Hey I have a 74 Scamp too!
I am dropping a 413 into mine.

As far as mounts go Schumacher has bolt in units for $159.
Or you could use a motor plate / elephant ears and midplate. $$$$$

Trans. will bolt right up to the crossmember. 8)

Cheap B Body headers will fit with the low deck B engines, just need a few dings here and there.8) I cannot go this route unfortunatly with my RB 413.

I would look into a Dana 60 rear end for the power you plan to make. At the very least a 8 3/4. The 7 1/4 or 8 1/4 thats in there aint' gonna cut it!

Don't forget your subframe connectors.
 
Ya for a drag car I would say at least solid mounts ans a torque strap. Or a motor plate should do it. For the power you are putting in the car I would say a good set of subframe connectors are needed. You will allso need a minimum of an 8 3/4 rear with a spole. But I would say you are going to break any thing but a Dana 60.
 
not to insult you but do really think a 906 head is going to flow enuf for 650 to 700 horse i dont see it not with a cast head that doesnt enuf cfm even opening them up wont flow enuf for them number but please somebody inform if im wrong
 
I don`t see that much hp either in that combo but regardless you really need to think your build through, especially if this car is a drag strip only car. An engine with any real power is going to target every weakness in a 318 Scamp. See if you can find a friend or shop that can educate you on the modifications you`ll need to safely install that 383. Perusing this website alone will help a lot. There`s too many things to list ,but look to replace the complete rear end, driveshaft, add frame connectors, tubbing?, frt.brakes?, radiator?, motor mounts, torsion bars?, headers/manifolds, wheels and tires, and the list goes on. Oh, it`s costly too ,so be prepared to say goodbye to a lot of greenbacks. Here`s another thread with some good info: http://www.forabodiesonly.com/mopar/showthread.php?t=6219
 
leave the stock tires on there and the rearend will be fine .:cheers::cheers:..
lol
my dart with the 440 and 7 1/4 was fine when i had the 175 80 14's on it ..
but it wasnt fast..(well the speedo said it was fast...)
 
We are porting the heads and are going to see what they do. I am also working on getting a set of Edelbrock Vic max wedge heads, which will make the power. I have been thinking about doing an aftermarket rear. Subframe connectors are on the list. You don't think the front discs will stop the car? I will be using a dynotech engineering driveshaft. There sure are a lot of naysayers around here. I am looking for some info, not "its gonna cost too much, you can't do this, that won't work" Come on guys, be supportive, not negative. I asked because I have heard of some issues with fitting a 383 in there, I just needed to know what mounts to use. this is not the first car I have built, just the first Mopar. Will I need a dropped centerlink?
 
This is the route I was going to go with the B block install. http://engine-swaps.com/noframes/home.html I don't see any reason you could not use solid mounts with this kit if neccessary either.

Like I said my first 400 going into the car is going to be relatively mild. I don't plan on increasing HP or torque much until I can get the car to hook and launch strait. I will most likely go with Motor plates when I install the 502 ci engine.

I saw in the new Summit catalog that Moser has an 8.75" housing for A bodies now. I was thinking of going that route myself for the rear end. Schumacher has under chassis B/RB headers.

The only other 'Fit" issue, besides the hood possibly, is the power steering gear box. I was going to look for a Manual gear box for mine.

I'm not sure about the dropped centerlink since I'm not that far along with mine atm.
 
Your front disks will stop the car fine. I have the 1973 & up a body manual front discs and stock drum brakes in back and the car stops good. The car is my daily driver BTW
Picture638.jpg
 
I Put a 440 in my /6. You can look at it and read it all here

http://www.forabodiesonly.com/mopar/showthread.php?t=33454

I don't think that the people on here are negative, we just don't want you to go through all this work and have something else brake. and then what? you have a big block scamp lawn ornament. It sounds like you are spending some money, yet you want to keep the stock rear? it doesn't make sence. It WILL go boom, esp. if you are guna race it. Your car is only as strong as your weakest part. I put a used 4 spd in my duster, and guess what...I am guna have to pull it because it wasn't looked over, and the parts where weak. Once you have 400...450......700 horse power, your "used" or weak parts won't last.

some heads up on things you WILL need....

motor mounts from schumacher, or elephant ears You can make them yourself, and most race cars have elephant ears.

187 oil pan, but you might be OK if you have elephant ears. You WILL need this pan if you use motor mounts. ( I don't know if this is just a 440 issue)

Frame conectors. i wouldn't trust just a roll cage. They help when you roll, and they do help the streigth of the car a bit, but Frame conectors are a must

Drive shaft will need to be shortend if it is for a stock A body. The tranny that you are using has a longer tail shaft, therefor the driveshaft will have to be cut.

Change your Rear end. you will have trounble conecting with one tire fire, and it will blow up on you because you are going to be putting wider tires on it. I am fine because I'm not tubing mine, nor am I racing mine, I also have a 8 3/4 sure grip, not a 8 1/4.

For race track, I have been told that /6 T bars work better, for a better launch. My car has big block T bars in it. I would recomend either swaping out the 318 ones for /6 or big block ones.

If your car is power stearing, you may run into problems with instalation, and no room. My car was manual, and the 440 fit in but I have heard that you can't fit some power stearing boxes with a big block...this could be false though

You also may run into problems with the power brake booster. You may have to switch to manual brakes, or buy a different smaller booster. again, I don't know this for sure, but there isn't much room in my car for anything.

as far as headers go, I would do fenderwells ( I hate them) but for racing they prob are your best bet for price and performance.

Your brakes ARE fine.

and after you consider all this...there are prob another 12 things that I have forgoten....I AM NO EXPERT!

Phil
 
TONY GTS said:
Your front disks will stop the car fine. I have the 1973 & up a body manual front discs and stock drum brakes in back and the car stops good. The car is my daily driver BTW
Picture638.jpg
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Your exhaust is sure low, WHere do you get groceries? I don't know a parking lot without speed bumps anymore

Phil
 
I have ordered the Schumacher mounts this afternoon. I was just asking about the rear, I really didn't expect it to hang with 650 hp, but then this is my first (technically second) Mopar. I am used to building fast Buicks. As far as the brakes, I will likely be switching to a hydroboost since vacuum production is not likely with my cam. Power steering would be nice to keep. We shall see. I planned on subframe connectors from the get go. What do you guys suggest- off the shelf or build your own? I am loking at the Milodon hemi low pro pan, Schumacher said that one works. I have 10" Toyo slicks with Centerline Fuel drag wheels. I have been trying to decide what rear to go with, a fabbed 9" like Currie or a custom d60 like the Strange S60. This car is being built for a specific purpose- 10.5s or faster. I just wanted to pick some Mopar brains, I have a mechanical engineer helping with chassis set up, he has built tube chassis cars and several serious dragsters. It should be pretty fun!
 
72chargerguy said:
I have ordered the Schumacher mounts this afternoon. I was just asking about the rear, I really didn't expect it to hang with 650 hp, but then this is my first (technically second) Mopar. I am used to building fast Buicks. As far as the brakes, I will likely be switching to a hydroboost since vacuum production is not likely with my cam. Power steering would be nice to keep. We shall see. I planned on subframe connectors from the get go. What do you guys suggest- off the shelf or build your own? I am loking at the Milodon hemi low pro pan, Schumacher said that one works. I have 10" Toyo slicks with Centerline Fuel drag wheels. I have been trying to decide what rear to go with, a fabbed 9" like Currie or a custom d60 like the Strange S60. This car is being built for a specific purpose- 10.5s or faster. I just wanted to pick some Mopar brains, I have a mechanical engineer helping with chassis set up, he has built tube chassis cars and several serious dragsters. It should be pretty fun!
Click to expand...
sweet, i have a 69 riv, what kinda buick you got.
 
Don`t feel like we`re being negative chargerguy, just realistic. Your 1st post mentioned you had a 650hp 383 and you wanted to know if the 7.25 rear end was adequate. C`mon now, that question sounded like you`ve never built a high performance car before. Then your second post said that your 650-700 hp 383 was made with ported 906 heads. I had a very similar .060 over 383 ,12.5:1 cr, ported/polished 906`s ,etc and it didn`t make near that kind of hp. Those two posts just didn`t set right from the start. You have a lot of good ideas and you can use some things on your Scamp but most everything will have to be improved in some form or another. Your front disc brakes will be fine, the rear brakes will have to be upgraded with the rear end. Drag only you can use an old set of shocks and keep your 318 torsion bars. Oil pan clearance w/idler arm & drag link may be an issue too. Mrtires posted a lot of things you`ll have to consider. If you go with Victor heads , they will make good hp and you`ll have to go with a better header than the Schumacher. The Moser 8.75 is good but you could probably have a Dana for the same money and have a huge choice of race quality gears. A good ,fast ,safe, and dependable race car starts with the chassis. If the chassis is right then the powerplant is immaterial. A lot of people get into one of these swaps and don`t have any idea how much is involved. It sounds like you are aware of the costs and dedicated to making it happen so if we can help here ,let the questions fly.
 
Not to belittle this sight or anyone here. Lots of knowledge/knowhow here!

But this sight may help you in your quest. Great tech section!

http://www.bigblockdart.com/

As for frame connectors,the above sight has a do your own page. As well as a page on converting your K frame to a DC big block frame.

I personally like these and will be using them. Several people here have purchased them and were very happy.

http://www.uscartool.com/Aframeconn/index.html
 
Holy crap! 650hp huh? Wow you will need a dana 60 rear. A butt load of body stiffening (eg: subframe connectors and roll cage etc.) , BIG radiator, Solid mounts/elephant ears just to start.
 
I am installing a 383 / 4 speed with a Dana in my 68 barracuda coupe and aside from all the parts that have been mentioned here you can go with 2" TTI headers. They fit in with the slightest amount of adustment but you will have to lose the power steering. If it is a Drag car you are only going straight anyway! I am using the Shumacher mounts because I have them and installing frame connectors and SS springs etc. If you make close to 650 HP you should have no problems hitting the 10's. There should be no reason for a bottle. May I suggest that you run alcohol instead of gas. It will keep your car running cool and make a little more power.
 
72chargerguy,

Your really starting to not make sence, at least to me anyways. Your original post was very vague, except for the part about the rear end. Then you tell people to stop being negative, when we were all just giving advise. Then your engine HP starts getting bigger the next post you make.

you say that you are just going to have a roll cage, then You are going to have a cage and Frame conectors,

Then on your second post you are saying that you are just needing info on Motor mounts. and jwsewell answers that right away, as well as burntorange70. and your next post says that we are being negative. and saying you can't do it...and you ask AGAIN for what motor mounts to use,a dn that you have heard of issues with fitting in 383's. You get more tech advice with installing a big block from a couple more people,
and after getting tons of info, without so much as a thank you to anyone, you finish off with saying that you just want to pick some mopar brains!?!?!. About what?...anything that is said comes across as negative to you.

I'm not mad, just finding your posts kinda frusterating.

My advice...

type down a long list of what you have in parts.
type down a list of what HAS been done to the car
type down a list of what parts you have orderd
type down a LONG list of what you are going to do to the car, and your goal

then....

ask specific questions. that way we all know what info you are looking for. I have no clue what you are asking from anyone anymore because your motor mount question has been answered a dozen times.

I hope you whent with elephant ears. they are way stronger.

I would like to see a pic of the mounts that you bought if you can post them when you get them.

and sorry if I offended you, didn't want to, just wanted to clear things up, I know I'm not the only one scratching my head.

Phil
 
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