I want to set the mixture screws on an edelbrock 750 for my 390. Everything i've read has people saying you turn one at a time till it bottoms out and the engine runs rough/stumbles, then turn it back out till max idle and do the same for the other screw....Well when i do this my engine doesn't stumble, it idles higher, what's the deal here?
I'll agree that i used to have a vacuum leak. It was a bad brake booster and actually, when i changed it out, is when this started happening. It used to idle down when i bottomed the screws. Once i changed the booster (old one would idle engine down pretty low whenever i'd brake), this occurred.
Yes the choke is open, i let the engine get up to running temp to do this. The only thing i don't do is set the actual idle itself by tach because i don't have one so i just guessed and it sounds about 800-900.