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red82gt · 03-03-2003, 07:32 PM

If it stutter on tip-in move the accelerator pump arm to the next hole. On deceleration, the vacuum is going to rise sharply and that's probably pulling the step-up spring right down pulling the metering rod right down. Try using a stiffer step-up spring. I learned a lot about tuning these things last year trying to get my car run to it's potential (they're virtualy identical to a carter AFB). I gave up and put on a 650 DP (judging by the night and day difference on the SOTP dyno) I'm hoping to be easily in the 12's. For a van you'll probably like a 750 with vacuum secondaries better.

03-03-2003, 07:32 PM	#7
red82gt Sober voice of Reason Join Date: Nov 1998 Location: Kelowna, B.C., Canada Posts: 1,514	If it stutter on tip-in move the accelerator pump arm to the next hole. On deceleration, the vacuum is going to rise sharply and that's probably pulling the step-up spring right down pulling the metering rod right down. Try using a stiffer step-up spring. I learned a lot about tuning these things last year trying to get my car run to it's potential (they're virtualy identical to a carter AFB). I gave up and put on a 650 DP (judging by the night and day difference on the SOTP dyno) I'm hoping to be easily in the 12's. For a van you'll probably like a 750 with vacuum secondaries better. __________________ 393W: AFR 205's, hydraulic roller, TKO600.