Quadrajet Problem Solving > Diagnose a Quadrajet carburetor problem

Bog From Dead Stop

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BanditRich:
I am inclined to say it is more of a lag than a bog; it doesn't fall on its face from a dead stop it just is slow for the rpms to rise and slow to accelerate. Like I said from a dead stop it feels just like the car is bone stock with all the emissions crap, closed hoodscoop, unmodified carb and restrictive factory exhaust system. I've had 5 late 70s TAs the 1st was in 1984 and couldn't change anything on them due to emissions testing aside from opening the hoodscoop; and it accelerates from a dead stop like the 1st few I had.
 

BanditRich:
I'm going to get the electric choke to work like it should before I adjust the air valve spring and see how it is after that. As it is right now I start it up and it idles in park around 675 rpms no matter how long it sits and as soon as I put it in drive or reverse it immediately drops to around 450.
I think it should have better acceleration if I get the choke working correctly so I can turn the idle up so as soon as I tap the gas when it's warms up it will drop to around 675. I think I have the idle speed screw set too low due to the electric choke not working correctly.
As far as tire spin goes I just put brand new tires on when I got it out of storage. It has the WS6 package with the 8" rims and I went from the stock P22570R15's to P25560R15's. Now my car is a mirror of the Macho TAs it has every mod those did and it also has subframe connectors.
The old tires were OLD. They were the same ones that were on it when I bought it in 2002 with a date code of November 2000.
My goal isn't to get the tires to spin it is maximum acceleration  from a dead stop & at any speed.
Once I do the suggested adjustments I'm sure I will be a happy camper.

Cliff Ruggles:
The most ideal scenario is to launch without any spin at all, so tune for the smoothest transition and quickest acceleration even if it's not spinning the tires. 

If you put big enough or good enough tires on it then no doubt it's going to be hard pressed to spin them w/o "power braking" it.  Those engines don't have much going on for low end torque, especially the ones with the bigger chamber heads and 7.7 to 1 compression ratios.

Even the "HO" 400's topped with 6X-4 heads were barely over 8 to 1 compression. 

Compression is power (torque).  Low compression engines, especially smaller CID never make much of it, at least at lower RPM's.....that's just the way it is with these things.......Cliff

BanditRich:

"Do some full throttle testing from a dead stop.  It should come in clean without any stumble/hesitation or bog.  In most cases when it does those things a little more spring tension is required.  If it seems to "lag", try a little less spring tension. "

[/quote]
Cliff are you referring to the air valve spring or the choke pulloff screw? And what you said about getting the electric choke to work properly  -  I just loosen the screws and turn it?

BanditRich:
I adjusted the electric choke but it still won't kick down. And I must be blind as a bat. I see the air valve spring in the diagram in the pamphlet of carb adjustments you sent me with the HP kit but I can't locate it on the carb. Where exactly is it? Could you or someone else please post up a pic?

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