10.2 : 1 compression 360 at sea level. Options?

mderoy340 said

Agree. Most folks with AFR gauges lean the idle to 14:1 and carb motors need to be rich at low rpm high load (coming off idle). Fully warmed up with airgap manifold my motor needs 12.5 at idle in gear to transition properly. Don't use the gauge to set idle mixture, give the motor what it needs to run properly.

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Dealt with that same situation and came to the same conclusion... The bigger plenum on Air-Gap manifolds only makes it worse too. Another note, engines with high idle vacuum (mild/stock engines) actually tend to need more accelerator pump shot volume due to the bigger drop in manifold vacuum when the throttle is cracked open compared to a "racier" engine with lower idle vacuum. I read that in David Vizard's Holley Carbs book, kind of blew my mind for a minute lol. Has to do with the fuel condensation on the inside of the intake manifold I think...