Hello,
I would like to here pro's and cons on a 383 build up,such as 5.7- 6.0 in rod,compresion ratio's,cam idea's, head work,ect.
I have LT1 Hot cam kit and ,ported heads. Clutch,T/B'S, headers, fuel pumps, injectors. Any idea's would like to do it right one time so I can drive it not work on it.
Thanks,
Ron

 

I would'nt go thru the expence of changing rod lenght,probably your old rods will work.
Id go with 10 to 1 compression unless you want to worry about octane.
A solid lifter cam will add 15 HP over a hydrualic. :chevy

 

Get Lingenfelters book on modifying small block engines. He covers most of this stuff in the book.

 

I've done a lot of research on this topic and would do the 383 with all forged bottom end parts. You generally want to have the longest crank to rod ratio as possible and stay above 1.5:1 for longer term durability. The longer the rod the less angularity on the side of the cylindar wall and ring area. The 396 will give quite a bit more torque, but if you do not have a "specialist" such as more performance with the CNC mill to clearance your block they will most likely hit the water passages. Depending on smog and what you want your car for, I'd stick with forged bottom end parts, a mildly aggressive cam so you can run hydraulic lifters, and a good set of heads. I've come to the conclusion that the C-4 vette is a GREAT autocross car, but lacks in the 1/4 mile since it is not a very big block and the frame will never handle serious power. With that in mind who really cares if your car is a low 12 second car or a mid 11 second car. A built 60's big block car will eat a C-4's lunch in the 1/4. On the other hand a nice 383 C-4 with about $3K spent on suspension and brakes is an awesome all around track star that is almost impossible to beat. Be aware that a 383 converion will set you back around 10K. There are numerous hidden costs that aren't even considered until it's too late and the engine is on the garage floor! :eek:

 

BlackRocket - you do know that there are guys running 10s with C4s ?

I have felling that the C4 frame is better than any frame on cars that were designed before it. A good 383 will run mid 11s with traction. Hitting the water jacket isn't that big of a problem. The block can be clearanced for the parts being used by hand. Then it should be pressure tested. If it leaks where it was clearanced, the bottom of the water jacket where the leak is a can be filled in.

 

I agree that you can run 10's and even high 9's with a C-4 but if you try to put a 520 cu in merlin in a C-4 chasis you won't pass smog and you can say good-bye to the frame and the windshield. All I'm saying is that for the $$$ you can build a much faster 1/4 mile car using an old camaro or cuda. I love my C-4, but the car will never be that fast in the 1/4 mile and is much better suited for autocross. ;)

 

Isners, I agree with blackrocket on the rod length at least. Just make sure you get the rotating assembly all at the same time from the same people so they will get the stroke/rod length/piston height right for the whole assy. I also prefer the forged to the cast if you plan on racing it or adding nitrous/blower. If you start out will a strong bottom end, you can then add anything else you want without worrying about whether the bottom end can take the stress.
Just my .02 :D