Q-jet adjustment 1977

[john1977]

Can anyone tell me how to adjust a Q-jet to get the four barrels to come in sooner? I think this may be part of my problem that it won't turn the tires over from a standstill. Its a stock block,bored 30 over,mild cam,flat top pistons, performer intake,headers,true duals, stk dist. 3:36 gears, dart iron eagle 202 /160 heads, rebuilt th350 with shift kit. After you nail it ther is a short pause (not stumble) before it really takes off. If anyone has any ideas, I would sure like to hear them. PS: its now 350hp and 9:5 to 1 comp.

 

[Bob Chadwick]

John,

I just adjusted my secondaries and made the "quadra bog" go away. I lost the water pump as I was messing with it so I don't know what else it did for my car and won't be able to tell until I get a pump back in.

On the passenger side of the carb in the back is where the mechanism hooks to the secondaries is a screw that controls the spring tension on the secondaries. Screw Picture You loosen or tighten this screw until you just feel tension then give it another 3/4 to 7/8's of a turn.

First you have to loosen a set screw underneath. Set Screw Picture Beware that as soon as you release the set screw all tension is going to go out of the adjusting screw. Not to worry, just turn it until you get tension and then give it the additional.

Bob

 

[clar2001]

Your secondaries might not kick from idle,but should soon follow have you ajusted your timming from what your running you should be able to smoke em from a stand still just by laying into the peddle.
The moment of hesitation is whats killing you,tuned properly it should never do that.
I'm running a Q-Jet Edelbrock 1903 my secondaries kick in to easy haven't ajusted that screw as Bobchad said..........mine is in the same place just looks different.

 

[john1977]

Thanks bobchad for the pictures, do you think this could cause it not to produce the torgue to spin the tires or should I be looking somewhere else. Like I said, its not bogging when its floored but takes a couple of sec. before you feel it really take off.

 

[clar2001]

You diden't say if your running Vacum Secondary or manual.
Do you here or fell them kick in durring normal driving, that deep tone they amit so you know your gas gauge is going down

 

[MoeJr]

John get your car up to full operating tempurture and the choke fully released. On the secondary throttle shaft on the lassenger side you'll see a silver prong sticking thru the shaft. make sure it is clear of the lock on the choke pull off. it is very common for the lock to not come off if the front throttle butterfly isn't straight up. On the secondary flapper screw less tension will open the blades faster and more will slow them down. Too loose and you'll bog so be careful.

 

[Bob Chadwick]

Can't hurt to give it a try. That short pause is the bog that I had. It helped mine and took all of about 10 minutes to do. Most of that was taking off the air cleaner and putting it back on.