So i recently found out that my stock Qjet carb is not acting as it should, when i adjust the mixture screws you should be able to almost stall the engine out, or stall it out completly, however my engine still runs strong with the intense scent of unburned gas and exhaust. I know the carb is bad, my question is which carb should i get as a replacment for a bit of performance?, edelbrock or holly?

I hear good and bad about each, what is overall the better of the two?

Also i hear talk of a part that if its an aftermarket carb, then it must go from the carb to the transmission, whats that all about?

Thanks, Trent

 

What you're describing simply means your carb/engine is improperly adjusted. If the throttle is open too much at idle, you can close the idle mixture screws down and it will keep on running through the main circuit.

The #1 cause of carb problems is an improperly performing ignition, either from wear/age or maladjustment. Make sure that is all up to snuff first.

To use an Edelbrock or Holley, you either need to get an adapter to go from the spreadbore stock intake to the squarebore carb mount, or get an aftermarket intake with the squarebore carb mount; and an appropriate TV cable geometry connector to attach to the throttle arm.

Why not just fix the q-jet? It's possible it's FUBAR'd, but it's also quite likely it just needs to be allowed to do what it was intended to do.

Be a shame to put all that money into an aftermarket carb downgrade only to find out your problem was ignition all along.

 

well we checked the ignition timing and its running fine, shop manual computer says it should be 6 degrees before TDC, i should have mentioned that im in college doing automotive service technician, and we haven't covered fuel systems yet so i dont know much about it, im just relaying the information from my instructor to here lol.

On the bottom of my air cleaner there are 2 ports for hoses, vacuum hoses im assuming, however no hoses are going to them, what are these ports? I know a vacuum loss can cause rough idle, would it possibly cause the engine to idle up to keep itself from stalling out?

 

the hoses on the air cleaner are for the flaps to close during warm up it pulls hot air off the ex manifold, if you do decide to go with a aftermarket carb you will also need to get a new distributor as well because they work off each other you will have zero advance because the computer doesn't know where the throttle.

 

Canadian car = non-CC.

Your air cleaner may not fit, depending upon the carb you get. Won't fit dual feed line Holley carbs, for instance.

I'd really try to find out what's wrong, rather than just replacing the carb. The q-jet is a much better choice for your basic driver & street/performance vehicle, and shouldn't cost you more than the new carb and what it will take to get it running properly.

 

Only most LG4s. If he has an L69 like his info says, it'll be CCC.

 

Good point. I take "H.O." with a grain of salt.

Dude, what's the 8th character of your VIN?

 

VIN says G for the 8th digit, we found some vacuum lines not hooked up today so we went ahead and plugged them in, the 2 ports on the underside of the air cleaner, we took a hose and ran it from the back of the carb to one of the ports, then ran another hose from the second port and ran it around the outside of the air cleaner where a hose would normally go and plugged it into the flapper where it would draw the heated air from the exhaust manifold.
Also the distributor I have is an Accel, factory one was shot so my father pulled it off a Camaro in the junk yard.

 

the distributor being changed could be a problem tuning wise on the stock carb because they work together so in that case go with a aftermarket carb depending on your use of your car depends on what carb to go with Holleys are more for racing and the edelbrock type carbs are more daily driver friendly.

 

well if people are encouraging me to keep my Qjet then id rather keep it and fix it if it will be a decent performer and respond well to future upgrades, im not worried about gas mileage, would like a carb that can perform well, is there any way that the carb can be tuned to run well with this distributor?

As for the rough idle on the car, im going to broaden my horizons from blaming everything on the carb and do a compression test on the cylinders friday, hopefully, its a simple spark plug, and I hope its not a burnt out valve or piston rings. I'll post up the results.

 

Okay, I stand corrected. VIN G is a L69, and you should have a computer controlled distributor with the computer controlled q-jet.

 

without the ccc distributor the ccc carb we not work right because the computer is not getting the right info the carb and the dist work as a team take one out of the mix the other will not work right. If your gonna keep the ccc carb see if you can find a ccc dist .

 

Absolutely! The CC q-jet is a fine street/performance system when it's allowed to do what it was designed to do.

 

Five7kid

Fighting the good fight, one thread at a time...

 

Hey guys, sorry it took me so long to reply, I managed to find another Q-jet carb identical to the one that was origionally on the car, put it on and it works best kind, only problem is when i took the brass fitting out to take the fuel filter out I didnt realize at first I had to use another wernch to hold the fuel line fitting still and went and kinked it off haha, so now I have to make a new line from the carb to the fuel pump, i took it for a test drive with the kinked off line and it was fine from idle to 2500 RPM but after that you could tell the engine was starved of gas haha.