So I went to the shop to fix erratic Idle and they drilled out the idle circuit to 40 thousandths and made that much better but now I get studder when I step on the gas. I spent 450.00 to rebuild that carb and another 357.00 to get rid of the idle problem so I would like to hopefully make some small adjustments to get rid of the stumble and put this to bed. Any thoughts?

 

secondary flap is opening too fast...

look on the net..theres an allen screw you loosen and tighten...it loads spring pressure on the flap so it doesnt just slam open....which leans it out and produces a stumble when you jamb it to the floor....not sure thats THE prob..but its simple and id start there...its something people always over look..always...and its a simple fix...i havent done it in so long, i forget the exact procedure..but its easy to figure it out

its on the top plate..you could adjust it without removing the carb i think.

if you find a pete mccarthy Pontiac High performance book..it has a whole section on supertuning a Qjet.....its worth the price just for that inf all by its self