My buddy just had a 383 Stroker built for his F car. Before anything, I will let you know the details of the engine:

Comp cam 224/230 duration at .050...477/480 lift...110 LSA
GMP Aluminum "Fast Burn" cylinder heads
GMP TBI Intake manifold
Holley 670 TBI with adjustable fuel press. reg.
MSD 8366 drop in distributor
New ignition coil
All sensors new
Motorvation custom chip for this engine

Got the thing running with base timing set at 0 deg. with connector unhooked. Fouled all plugs, hesitated, missed,backfired.

Set timing to 5 deg advanced with connector unhooked, turned fuel pressure down to 11 LBS. from 13. Runs a bit better, more power, not fouling plugs, although still seems to be backfiring under load.

How much more advance can you run safely? I have heard all kinds of things from 6-14 degrees. It seems like it wants more advance, but I dont want to go too far and damage the engine. How will I know if I went too far? What does detonation sound like?

It seems like with this heads and cam, more advance would be okay. Right now with the connector hooked up and at idle total timing is reading 40 degrees with base set at 5 degrees...doesnt 40 sound like alot to you?

As far as fuel goes, I talked to Holley and the said their TBI is set at 13 psi fuel pressure out of the box. The said to turn it down to 11, which I did. I don't know , maybe I shouldnt have, now we are back to stock fuel pressure, and I think if anything this engine would want more fuel than the stock engine. What do you think?

I can't believe how much tuning is required for these TBI's!

P.S. the engine is definetely not the problem, the guy that built it is DAMN good.

 

Detonation sounds like someone is hammering on a anvil, if it is not too bad it will sound like a diesel engine. 40 deg. is alot, you may have missed the correct tooth when you installed the distributor and could be getting a false reading. You are correct in that the 383 needs more fuel than the stock motor but it is getting more fuel. There is more involved in how much fuel the motor gets than the fuel press. I think that the new motor is pulling less vac. (224/230 duration) than the stock engine did so the ECM thinks that the motor is under load and more fuel is added. If you turn the fuel press down too much there wont be enough fuel to support upper RPM, and if you turn it up to much you cant get a good idle. One way to make things more gooder is to get into prom burning. If you can burn proms let me know and I will let you know what worked for me. I am still working on my tune but have put a-lot of work into it. When people see 383 they will say you need to add more fuel, just give the motor what it wants and take advice cautiously.

 

I second the chip burning suggestion. You WON'T I repeat WON'T ever get it to run right without tuning the chip. That cam does idle with alot less vacume than stock and thats why its rich at idle, on the other hand I bet it won't even begin to rev past 3500 rpm because it will be completely out of fuel. The only way to fix this is to tune your VE and Spark tables on the chip to your new engine. I would steer clear of the mail order chips, you'll just spend a ton of money to get a car thats barely drivable and has OK power. If you learn to tune yourself then you'll end up with a great daily driver that makes great power. The only problem is it will take you several months to learn enough about chip burning to be effective and hopefully you won't burn a piston or wash the cylinders down in fuel along the way. The correct order to take on a project like yours is to learn chip burning on a tired stock motor and then move up to your new pride and joy with your new found knowledge.

If I were you.....I would throw a carb on it till you figure out how to burn chips, then swap back to tbi when your ready. You can do it in steps, timing first then TB. Thats what I did.

With that all said, feeding this 383 will be a pain. Once you start learning about TBI you'll realize that getting enough fuel is a major problem. If you have the 90 pph injecoters you'll probably need over 20 psi of fuel pressure and even then you'll be pushing it. That cam just makes too much power too high in the power band. I'm running a 350 with a 218/226 cam and I'm running 22 psi with 75 pph injectors and it barely feeds my motor. Those are the two biggest lessons I have learned when dealing with TBI. If you go the carb route I can show you a neat way to hook up a cheap carb fuel pressure regulator using the stock electric pump that will be easy to swap back to tbi. Hope I helped and good luck.

 

Monte is right on. add to the mix the desirable results you get with a WB02 at your disposal. sure would make it so much easier.