tuning a Holley DP on a 396BB, used Vacuum method still running rich

[cactuss4]

So I found my carb was at the standard setting, 1.5 full turns out, giving me a rough 15hz of vacuum, turning them further out didn't help, but I noticed that I could get to almost 20hz by turning the screws in, so I ended up at 1.5 out from fully in. Car seemed to idle well but the response was tough and giving it gas made it pop (don't think I damaged the power valve). So I pulled over, took the screws about 1/2 out and that seemed to clear things up, seems responsive, no more popping no bucking etc.

The issue is that it's still running Rich from a nose perspective. Side exhaust means the car is a tad stinky. Wondering what else I can do, or other tricks to get a Holley DP with electric choke to run a bit leaner without causing the weird idle and the backfiring through the carb..

I may not be able to do anything, but I don't think a car has to run this rich to "run".

Thanks
tory

[MonzaRacer]

2 things can,be done, bending and inserting say a 0.015 size wire in idle fuel channels can lean them up a bit, you can go up or down on that size, the gasket will hold it in place. Also lowering the PV rated opening can,help I tend to run 5s and lower ratings. Resisting timing, idle, accelerator pump arm are all needed. Remove vac advance, get timing up around 14-18 initial timing and idled as low as possible le, then hook vac advance to manifold vacuum. Then reset idle speed. Now adjust accelerator pump link it should have 0.015 play but I just do it by feel. I hold lever up on cam and check by hand. I like to "just" feel the arm being loose. But that can be varied to compensate for launch issues.

[gordonquixote]

Have you tuned the choke by clocking it (clockwise is less tension)? Maybe you are running at partial choke after warming up.

[cactuss4]

Have you tuned the choke by clocking it (clockwise is less tension)? Maybe you are running at partial choke after warming up.

Have not considered this, since at warm up the choke seems fully open. I'll take a look.

I've now played with my bowls and things seem a bit more responsive, so maybe I'm making some progress.

Tory