Alright guys, this is for anyone who knows about Quadrajet carbs! I bought a used carb for my project car, (very cheap) which looks good and idles good... No leaks, etc.

The problem is, it works perfect off idle to maybe 2,000 rpm and then seems to bog/break up. It's pretty undriveable the way it is. I've already checked the vacuum operated choke pulloff, and it seems to function when vacuum is applied. What else can go wrong with these things? Qjet's have always been a difficulty for me (they look so simple, but tick me off so bad!), so any help is greatly appreciated. Thanks!

Hellraiser

 

What type of q-jet is it - computer- or non-computer-controlled?

What type of distributor do you have in it?

Did you replace the fuel filter?

How did the car run before you put this carb on it?

With this information, we should be able to give you a better idea what's wrong.

 

Ok, here's what i've done to this car so far -

It was originally a TPI injection setup ... which i've removed and replaced with a new intake and used carb. While the intake was off i removed the heads and had new guides and a valve job done. I've dropped the tank and removed the original electric pump, and substituted a stock replacement mechanical pump.

It's a 5.7L with an edelbrock performer intake, non computer controlled carb (from 1973 camaro), non CC distributor with vacuum advance(junkard unit with new cap,rotor,module), base timing is currently at 6 degrees. The inline fuel filter from the injection setup is still in place, and was replaced about 3,000 miles ago. i hadn't thought to check the filter in the qjet, but will right now....


Hellraiser

 

You don't want the original filter in there. Fluid should be pushed through a filter, not sucked (variation on "shaken, not stirred"...).

Take that out and see how it goes. Change the in-carb filter while you're at it.

 

I hadn't thought of it that way.... The filter in the carb itself looked fine, but i'll replace it since its out. Thanks, and i'll keep ya posted.