Qjet APT function, operation and adjustment

[rfpowerdude]

How does the APT function on a Qjet? Is it a stop for the plunger that holds the primary rods? I need to fatten up the part throttle cruise on the Qjet in the silver car as it wants to be at like 17:1 at 30-50 mph. Turn it out (CCW) to fatten it? WOT is good on the wideband as is the idle mixture. I am going to adjust this weekend if I can figure out how to make a tool to turn it...
Thanks all!

EDIT: Nevermind. I have a tool and I'll play with it over the weekend.

 

[maxi426]

You've got it right. I have experience with a wideband and the APT adjustment. If you're at 17 to 1, I'd start with 2 full turns out to get you close. Fine tune from there.

 

[rfpowerdude]

🥳
Thanks!

 

[olds307 and 403]

That is really lean, I wonder what jets and rods are in that carb? I tap and thread a plug for the air horn and notch the adjuster for a small flat screw driver. A couple of turns out should get you where you need to be.

 

[rfpowerdude]

It's already tapped with an Allen plug and the the APT is notched for a flathead screwdriver. I have twisted it two turns out and I will test on Friday. It's dark everyday when I get home and I want to be able to play with it when it's NOT dark out. Friday is a day off for me, so I will report back!

This Qjet was done by Dean Oliver back in like 2011 and I don't have the info about jets, rods, hanger, etc. anymore (can't find it). And I def don't wanna take it apart just to document it UNLESS there are issues and I have to pull it apart anyway...

 

[Bonnewagon]

FWIW the secondary rod hanger shaft is the right 'double D' size to adjust the APT. So is the later idle mixture screw tools that use the 'double D'. Just grind a little off the bottom of the hanger and you are all set.