ok so i ditched the cc q jet and put on a Holley 600 car ran fine once i got it to idle took it for a drive and ran fine just a kind of dead spot stumble off idle on the way back home at a stop sign it just died now when i start it i have to keep my foot in the gas to keep it running i still have the stock distributor could this be the problem ? by the way this is all on a 1984 z28 with the l69 everything is stock except carb

 

You probably need to tune your idle screws with the car in gear and the parking brake on. Hook up a vacum gauge, and turn the screws a 1/4 turn at a time allowing a few seconds for the motor to adjust. Keep adjusting until you get the highest vacum rating. Use the gauge to get an idea on the base timing as well. Look at one of the sticky posts above that is listed as Holley tuning. That will give you a more in depth adjustment.

 

Are you still using the L69 computer controlled distributor? If you are, thats part of the problem... it only works properly with the CC Qjet as well. Get a vacuum advance HEI if you are using the Holley.

Other thing - check the accelerator pump linkage on the carb, make sure you adjust all the slack out of it. Adjust it tighter untill there is just barely no slack in the linkage. If there is slack, it will not give a pump shot of fuel at the right time, and cause an off-idle stumble.

 

morning from snowy Virginia. sounds like your car is running much better!

Personally, you might keep your stock carb & dizi & anything else associated w/ the carb/emmisions that you yank & set it aside for later. never know when you might want to try it again etc.

 

yes. like posted earlier you need a vacuum distributor

 

well whats the cheapest vacum advance hei distributor i can buy ive alredy spent 400 dollars on the car just this weekend i just want this thing to run

 

This is the one I bought when I switched to carb. I've had great luck with it so far. It's basically a MSD copy with the jegs brand on it. It goes for $129. Suppose to be more on the performance side.
http://www.jegs.com/p/JEGS/761348/10002/-1
This one is the same type but is more of a everyday driver version I guess. It's only $89.99 right now. That's gonna be the cheapest good dist. you'll find.
http://www.jegs.com/p/JEGS/755778/10002/-1

 

Go to an auto wrecker and pull a few out of some old cars and trucks. Check for play in the distrbutor shaft, and take one that feels the tightest. Take it home, clean it, put on a new cap and rotor set, and get the Mr Gasket advance curve kit (about $20) and recurve the dissy with a performance curve. Just use the springs though, not the supplied weights. Use the GM weights already in your distributor.

Could easily keep it way under $100 this way, and it will work just fine.

The new one posted above is a good choice too, but should also get the recurve kit if you get that.

 

The Mr. Gasket advance kit for HEI always made mine worse. A piece of junk in my personal opinion.

 

awsome ill go pull a couple from the jy will one out of a 350 work?

 

I had problems when I used the springs and weights in the kit, but when I used the MrG springs and the original GM weights, it seemed to work pretty good...?

 

305, 350, 400.... they are all small blocks, so they are all the same. Yes it will work

 

Springs is all I ever used. Their weights and cam stink.

 

ok so i went out and changed the timing just a hair and now it idles and runs strong just stumbles off idle and backfires if you just slam it to the floor ? could this be my solution i really don't want to spend any more money on this car

 

You can advance it so it idles right. You can advance it so it runs right under power. You can advance it so it gets decent gas mileage.

But you have to choose between those three. You can't even have 2 out of 3.

Get a proper distributor or put the CC q-jet back on. Fixing it was probably your least expensive route from the beginning. But, who listens. . .

 

well we were fixing the quadrajet but my dad was rebuilding it and broke the plastic piece that goes over the float so he got mad and just went out and bought a brand new carb i guess i will go get a new distributor from the junkyard this weekend then

 

If you pull a JY carb, I'd replace the Ignition module, or at least buy one and have the spare sitting around.

I had one go bad on me out of a JY carb in my old 85 Z/28.

 

You need to get the proper power valve in the Holley, go to their website for instructions, you will need a vaccum gauge, Power valces are $15 and the gasket kit $5 at Jegs. This will cause the hesitation to go away....