[dataway]

Schurkey the full choke gap to the air horn at the front is specified in Q-jet adjustment specs, it varies between years, models, engines, and you are correct ... choke pull-off moves it closer to 1/4 than 1/3 open. .. maybe 1/4-3/8" to the horn in the back. I'll measure it tonight.

Being this is not a daily driver I just cannot bring myself to send exhaust through the intake ... seen so many old Pontiacs just roasted to death by malfunctioning risers. I figure even open they create enough imbalance to send exhaust through the intake. I know all the reasons it is done, but just doesn't seem applicable to a weekend joy rider.

Carbking .... that would be my go-to solution except I hate running a cable into the interior and coming up with a mount for the knob. It's been my solution many times ... but you know, trying to keep this car as original as possible.

[dataway]

Schurkey .... went through the manual again ... the flap IS closed all the way stone cold, choke set ... the gap I mentioned is set with the engine on the second high idle step .. with I think no vacuum to the unloader ... it was to check the adjustment of the rod that goes up to the choke flap inside the carb. I thought it was to adjust the flap at full choke set.

And you are correct .... the choke flap with vacuum to the unloader is almost exactly 1/4" from the air horn on the rear side.

I think I can make this work if I can get the choke coil to pull a bit quicker ... I think I can bend the adjustment loop enough if I take the rod off and tweak the top bend so it doesn't bind in it's hole.

[Cliff R]

You aren't going to get good results with the crossover blocked. It takes quite a while to get enough heat in the intake then on to the divorced choke coil..........

[68 Firebird]

Divorced chokes work very well once set.
And yes the open crossover is your friend.
When mine was blocked took much longer to idle
Smooth.
This carb I setup with kit from Cliff last year.
Once set the choke assm is a thing of beauty.

[Schurkey]

Originally Posted by dataway

Schurkey .... went through the manual again ... the flap IS closed all the way stone cold, choke set ...

Thanks. I could not imagine any decent carb not fully-closing the choke. Well, the horse-shiit Demon carbs had truly-terrible chokes that, in effect, were prevented from fully-closing, 'cause they wanted to save a couple of bucks by not having a choke pulloff.

Originally Posted by dataway

the gap I mentioned is set with the engine on the second high idle step .. with I think no vacuum to the unloader ... it was to check the adjustment of the rod that goes up to the choke flap inside the carb. I thought it was to adjust the flap at full choke set.

That's still not the proper verification.

Choke closed, apply vacuum to the pulloff. Bump the throttle (to allow the fast-idle cam to rotate.) You should have an appropriate gap between choke blade and airhorn wall (about 1/4", but varies somewhat) AND the fast idle cam should be on the second step.

This verifies that the choke pulloff is adjusted properly, AND the link from choke blade to fast idle cam is adjusted correctly. Automatic chokes need four adjustments to be correct, and that's two of them. No-one ever dicks with the unloader, so the unloader is almost never out-of-spec. That leaves the tension on the choke-coil forcing the choke blade closed.

Originally Posted by dataway

And you are correct .... the choke flap with vacuum to the unloader is almost exactly 1/4" from the air horn on the rear side.

I'm thinking that with Q-Jets, the official procedure is to measure from the front side of the choke blade to the airhorn wall. Opposite of Holley. But everyone is used to measuring from the rear side of the choke blade.

Originally Posted by dataway

I think I can make this work if I can get the choke coil to pull a bit quicker ... I think I can bend the adjustment loop enough if I take the rod off and tweak the top bend so it doesn't bind in it's hole.

Take a look at the actual choke coil. SOMETIMES the bimetallic spring is adjustable in it's holder. You may need to set yours more "lean", assuming there's an adjustment.







Here in the Seasonally-Frozen Wastelands, there's still snow on the ground in places, from where it was heaped-up to clear parking lots. And it was snowing lightly on the morning of May 2; although there was no ground accumulation. This place SUCKS. We're having The Winter That Never Ends. Global Warming!!! But it did give a guy lots of experience dicking with chokes.

[dataway]

On my choke stove it has an access port to the slotted shaft on which the coil is wound .. which at first I thought was for adjustment. But I'm not sure .... tried turning it with a small amount of force and gave up as I didn't want to damage the brass shaft.

I came to the conclusion that the slot was just there to slide the coil on .. no idea why there would be a removable plug on a hole that is situated perfectly to turn that shaft ... if it doesn't turn.

Shaft has a swaged connection to the stove cover ... which may or may not allow adjustment, I can't really tell. Would be great if it did adjust ... I think I could get away with adjusting it on the very limit. The crossover does get hot enough to burn a finger after five minutes of running.

BTW .. the carb is a 1971 704, choke stove I am using is for a 68 ... not sure if that matters

[dataway]

Just so you can see what I'm working with ...

One pic with the choke set.

One pic with the vacuum to the unloader.

Shortened up the choke coil rod again and bent the angles nice and square so it doesn't bind. Testing it with a heat gun, which I'm guessing doesn't work as well as the engine running with the coil sitting down there in the crossover well, I can see the first start of the day might be a bit slow to get the choke fully open, but it does readily open all the way without too much heat.

I think after warm up and five minutes on the road the intake plenum will be plenty warm for the car to run nicely. I'll have the intake pre-heater installed also.

[Old Goat 67]

Only adjustment on that is bending of shaft to fit into hole at choke arm.

[Kenth]

Hose from pull-off should located here: (if open you´ll have a vacuum leak).

[dataway]

Pull-off hose was hooked up to a vacuum pump for carb adjustment with the engine off.