how to fix bucking
#21
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Lower your running airflow to 8.6. Part-throttle Lterms means above idle. If you're getting surging at idle you need to modify the RAF, as I mentioned, possibly the ve (out of curiousity, what are your Lterms and IAC's at idle a/c off?), and/or possibly the timing table(s) (as in pull/decrease timing). Drill the throttle body if you like, but my car runs like stock; a friend's car with same exhaust as mine, forged-stock bottom end, Stage 3 LS6's and a MUCH bigger cam than mine with 11.5:1 CR runs even better than my car does (My TB is going bad). If you drill your TB blade breather hole too much you will increase surging and will be forced to buy a new TB. I agree with P Mack about 35 IAC counts at idle a/c off.
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Originally Posted by The Dragon
Lower your running airflow to 8.6. Part-throttle Lterms means above idle. If you're getting surging at idle you need to modify the RAF, as I mentioned, possibly the ve (out of curiousity, what are your Lterms and IAC's at idle a/c off?), and/or possibly the timing table(s) (as in pull/decrease timing). Drill the throttle body if you like, but my car runs like stock; a friend's car with same exhaust as mine, forged-stock bottom end, Stage 3 LS6's and a MUCH bigger cam than mine with 11.5:1 CR runs even better than my car does (My TB is going bad). If you drill your TB blade breather hole too much you will increase surging and will be forced to buy a new TB. I agree with P Mack about 35 IAC counts at idle a/c off.
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Ok, I found a log file that I forgot I had. It showed that at a hot idle, ac off, my iac counts were 110-115. It also showed desired airflow was 9.3. My stft were looking good at idle, about -4 to 0 although the ltfts still showed like +9 or so. It idles nice but my problems are cold start surging, and bad bucking under like 1200 or so. Hot starts aren't bad, but it still surges a little.