Quadrajet Problem Solving > Dialing in your rebuilt Quadrajet carburetor

A Little rich at WOT

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77l48:
I deleated the choke for simplicity. It had the hot air choke system. I retained the idle kick  up (terminology?) portion of the choke system, but removed the choke itself. It is not needed as near as I can figure.
 This is a summer only car and even at 40*, 20 seconds of me holding the throttle is enough for it to idle. At any summer temp it's not needed at all and will idle fine with the idle kick up function until it warms up.
 I also considered it an obstruction to flow on the primary side even after it was open. Is that incorrect?

Cliff Ruggles:
There are no negatives from having the choke and all the hardware in place for tuning or performance.

I like a working choke, especially if the engine is ever started in really cold weather. 

Those carbs are great candidates for an electric choke.  I ran my 1977 carb for years without one, but the older I get the less I could tolerate pumping the accl on cold days and "feathering" the throttle till it warmed up.  I re-installed the E-choke a few years ago, instant cold starts and fast idle so I don't have to sit there and keep it running.

Makes moving the car in the Winter time a LOT easier as well.....Cliff

77l48:
Thanks Cliff, maybe I'll get a choke in the future if I drive this car more often.
Got a good chance to try out the primaries on a steep 15% grade while staying on the primaries only. It seemed slightly lean with a slight hint of hitching on the pull.
Opened up the APT another 1/2 turn to make slightly richer and it seemed to like that better.
I am wondering what is the usefulness range of operation on the APT with your .044 primary rods.
Right now I'm 5 full turns out and must be approaching the point at which I've pulled the tapered section out of the jet orfice. At some point more turns out will not enriched the mixture, right?

Cliff Ruggles:
Nothing at all wrong with being up 5 or more turns and getting on the faster tapered portion of the rods.  This also sets the PP for much less movement to get up on the smaller .026" tips, so faster throttle response, etc. 

That's why we use the full tapered rods in lieu of "stepped" rods like the "K" and "P" series.....Cliff

77l48:
Thanks cliff! That gives me some room to go richer when the temps cool or I drive to a lower alt without having to change the jets then.
I have it tuned now so that it runs strong through the entire RPM range even the 2500 to 3500 range. It just wanted less fuel. It's always a little unnerving when approaching leaner and leaner conditions.
I have side pipes and the noise from them I afraid could be covering up pinging that may occur if I go too lean. So that leaves me checking the plugs fairly frequently during jetting changes.
Thank you very much for your advice!
Also really enjoyed your book. Very well written with excellent photos and step by step procedures as well as the recipes in the back. Awesome read!
It's the only reason my Q-jet runs as good as it does now. :) :) 8)

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