I'm just having fun with carbs this week.

The first problem I'm having with the Holley 80457. This is the carb thats on my Elcamino. I'm running rich at an idle and I cant drop the AF ratio enough to clear the idle problem "SMELL" without running into issues. This has 61 jets in the primarys already.

Question is if I were to jump UP a few jet sizes where I could use a larger range of adjustment on the AF mixture screws then lower the idle screw; would it be possible to rid this rich smell in idle this way??? I admit it doesent sound right but I'm thinking it might work.

2nd issue I'm having is with my Demon on the truck, 750, mec 2ndary. For some reason If I let the truck sit for a few hours and then start it the plugs get gas fouled. It runs fine and if I dont let it set very long this doesent happen. Its not running rich and the fuel pump goes off with the toggle/ignition so the fuel pump cant be running. What gives here???

 

Changing jet sizes won't do anything for your idle problem. Thats a completely different circuit. Try blowing the idle circuits out with carb cleaner....sounds like one of the air bleeds might be clogged.

As for the speed demon.....thats an odd problem for a new carb. If the pump isn't running then it must be some sort of slow internal leak. take the carb off, make a stand out of some long bolts, set it on your bench while full of fuel and see if you can see if/where it's leaking.