NJChris

I have a 1986 H code firebird, 305 carbureted. I got the car not running correctly, and didn't really get any information why. It will idle and move very gently fine, but as soon as you get on it hard it dies out. Because it has spark, I thought it was a fuel problem. I changed the fuel filter and put a new pump in with no difference. So then I had thought the carb was junk so I looked into swapping on a new non CC carb. However, in the process I had noticed the distributor was not the stock set up, the car has an aftermarket accel distributor, looks like an accel supercoil maybe. The car also had a 100gph 6psi fuel pump that would be great for a 600cfm holley, but the stock qjet rating is 9psi. It seems like at some point someone started to swap a non CC carb, and never actually finished the job. I would think not having any timing advance from swapping in an older style vacuum advance distributor and still having the computer hooked up would explain why the car dies when you get on it hard. My question is, how do I tell the difference between the stock style CCC distributor and a vacuum advance distributor? I'm going to put on a holley carb no matter what, but if I wondering if the distributor in the car is good for that already

zed-028

CCC distributors dont have a vacuum canister on the side of them.

if its got one of these, its vac advance.

http://image.superchevy.com/f/166959...istributor.jpg

i wouldnt be running anymore than 5-6 psi through a quadrajet either, i had to put a regulator on mine because it was blowing the needle off the seat at 9psi. And lets face it, its a 305, it doesnt need it.

if you get on the throttle and the car dies out it might actually be the opposite of starvation, you could be flooding the living bejesus out of it, as stated before, mine did that when it would blow the needle off the seat.

It will never run right until you either eliminate all the computer gear and go mechanical/vacuum, or get all the computer gear working well.

NJChris

I'd like to put a big cam in it, so the CCC is going away. The factory spec 9psi, which is what the stock replacement pump puts out. I changed the spark plugs and they didn't look like it was super rich, so I don't think that's the problem

zed-028

i get that the factory spec might be 9psi, but think of the application, the 305 is small turd of an engine (dont worry i have one too) that wouldnt requre anywhere near as much fuel as something like lets say... a modded 350 or a 400 pontiac engine.

poke too much fuel pressure in one end without the demand at the other and youll wind up with all sorts of fun issues that will usually lead you back to too much fuel pressure.

the rating on the box is often not a true reflection of what is actually putting out in practice. I had a pump that said 7-9 psi, was closer to 14. grab a gauge and check it. even better, grab a regulator with a gauge on it and you can not only check it, but change it on the fly.

Even our Q-jet Lord Cliff Ruggles doesn't recommend more than 7psi at any time.

NJChris

I did have a gauge on it. Didn't run any different at 6psi than it did 9 psi. which lead me to start thinking it wasn't a fuel problem, but maybe a distributor problem

zed-028

do you know now if it is a vac advance unit based on the link i posted?

NJChris

No it doesn't have the big canister on the side, so its not

zed-028

check to see if its throwing up any error codes. might even be something as simple as a distributor rotor, timing, the cap etc.

NJChris

no codes, cap and rotor look fine. It really doesn't make sense why it runs bad. Other than base timing being normal so idles right, but no advance so it dies, I cant think of any other problems

zed-028

if it had no advance it would be throwing an EST code.

could have some crap in one of the filters. change the one underneath then change the one in the carb. those are the 2 easiest starting points.

do the underneath first so if any excess crud starts moving forward itll get caught up front.