Author Topic: tuneing with an afr gauge  (Read 599 times)

Offline leanburn

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tuneing with an afr gauge
« on: June 08, 2013 - 10:13:52 AM »
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.




Offline Chryco Psycho

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Re: tuneing with an afr gauge
« Reply #1 on: June 08, 2013 - 11:34:37 AM »
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

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Offline leanburn

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Re: tuneing with an afr gauge
« Reply #2 on: June 08, 2013 - 12:30:23 PM »
ok, i wasn't sure if pump shot would be a factor at 4,000 rpm. i'll give that at try.

Offline Chryco Psycho

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Re: tuneing with an afr gauge
« Reply #3 on: June 08, 2013 - 04:13:21 PM »
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

Challenger - You`ll wish You Hadn`t