tuneing with an afr gauge

[leanburn]

so i installed an afr gauge the other day, awsome tool, takes alot of the guesswork out. i have the thing running within acceptable numbers through most rpms but i get a lean spot at about 4,000rpm when i smash the pedal. i can also feel it hesitate for a split second when this happens. what would be in need of adjustment? 4bbl power valve? oh yeah, carb is a 870 vacuum secondaries.

[Chryco Psycho]

More accel pump shot , higher float level in the rear bowl , it is going lan as the secondary open as there is no pump shot for the secondary

[leanburn]

ok, i wasn't sure if pump shot would be a factor at 4,000 rpm. i'll give that at try.

[Chryco Psycho]

it would depend how far into the throttle you are at 4000 rpm , when you stad the throttle for, there you should have some pump shot left , different cams will provide pump shot over more degrees of throttle shaft movement . I would raise the float level a little frst though