So my 383 is a terd!! Help.
So my 383 is a terd!! Help. Well you read the title, my car is a terd. Everything is holding up awesome, runs great, but the car just doesn't pull like I want it to. My 383 car barely pulls my 93 Z with a hotcam, mid lengths, and boltons. Eagle rotating assembly, edelbrock heads that I dont think flow for ****, even with the work done to them, 9.8 pistons, basically stock intake manifold, ported to 58mm, cc306 cam with 1.5 RR's. For now, I want the car as strong as possible all motor, plus I have a 150 shot, so that will help. This is my plan. I know the compression is low, I would like to supercharge it so the pistons that are in it are staying. I will likely replace the heads with a fully CNC ported set from ET performance. Cam, keep it or replace it?? 1.5RR's, keep em, or replace them with 1.6's?? ET heads, good idea? Intake manifold, are there any cost friendly options for the LT1?(not interested in the edelbrock intake that might actually hit shelves by the year 2074). Thanks in advance for the help!! 
It's your combination of parts, that's what is killing it. The Hotcam is way too small for something setup like that, even with the 1.6's. The compression ratio is alright, could go higher, but if you are going forced induction, get it a tad lower. Get you a big Cam in there with a 230's duration, about a .560 lift, and it will wake up.
id definately look for some well ported aftermarket heads like trickflows or afr's etc., higher compression would help if it stays n/a,port matchged intake to your heads, a custom cam that is big enough for a 383 with nice heads, and 1.6 RR's.
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Verdad Gallardo Yahh the edelbrock heads are going for sure. Honestly I'm not sure as to what was done on them. The intake ports are untouched, still the choppy machining marks from edelbrock. The combustion chambers are where most of the work was done on them. Honestly I don't know much about the heads, other than I believe they only flow in the 240 range on the intake side at .600 lift. The compression is definitely a problem, but since I plan on going S/C, I would rather leave that alone(unless convinced otherwise). The intake is an untouched other than porting for 58mm TB factory LT1 intake(bottle neck). I simply dont have the cash this year to go through with the forced induction, and I would like to do all I can at this point to get the car to run as strong as possible on the rotating assembly that I have. If I only had another set of Fikse wheels to sell!!
Honestly I'm not so sure now. I've been tossing around the idea of pullin the motor this winter, swapping out my pistons, selling the heads that are on it and going with the ET heads, and going with a custom grind cam. Then I can still run my 150 shot that I have(which gets me to where I want the car to be all motor). I'm really leaning towards the full conversion to a high compression all motor setup, and have been since the day I put those pistons in it.
I still think its the combination of parts that killing you. You cant have a f/i motor and expect super things from it n/a. Sure the n20 will help out alot but it wont be were it could or should be. Before building any motor the is on of the choices that you have to decide on. Is is going to be a f/i motor or n/a and build it accordingly. Good luck man. 
Originally Posted by FANTA-Z
Yeah I would pull the pistons go with some flat tops and spray the motor. You should be able to get in the mid to low 11s on motor with some really good flowing heads and a nice tune.
Ya see the thing is, on my setup, with poor flowing heads and a stock intake, and low compression, before NOS with an unlocking convertor, on a 1.79 60', I was still turning 11.95's all day long on the most poorly maintained track in michigan, where my stock car was .3 seconds slower than at Milan, the best track around. Which I guess is all the more reason to pull the motor and do the swap to some 11.5's or so, (if the car did that well with that poor of a setup, imagine if I did it right). Well, I believe this project may be changing directions.
Originally Posted by 94strokedz
No no no, the hot cam is in my other car, a basically stock 93 Z28, my wifes car actually. Mine has a CC306 in it.
I think it's the parts.. get that Compression up, and get a meaty Cam in there, and it will wake up.
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those heads are choking your motor, and some 1.6 rockers would help. That compression has to defiantly go up or supercharge, or turbo that bitch up. 
That CC306 should still make some good power on that 383, but there is always room for improvement
That CC306 should still make some good power on that 383, but there is always room for improvement