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al lkosmal al lkosmal is online now
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Join Date: Jul 2001
Location: mt. vernon Wa. USA
Posts: 8,761
Quote:
Originally Posted by Nux View Post
Thanks Al - I'll try that. I did set the ITB's up according to Clay's guide, and it runs quite well. It seems that MAP is way over 100, which may in part explain why my tune is somewhat off. At idle I'm seing MAP 40-60, whereas with plenum it was more like 20-40. So my initial AFR ratios are currently not correct.
I suspect that your MAP calibration is incorrect. 40-60 at idle is ok, but wide open throttle (low/no vacuum) with normally aspirated engines (no turbo) would only be at local atmosphere or so...i.E. 100kPa.. have you been data-logging to review the areas where you are going lean/rich?

I've had excellent results using Speed Density (MAP) tuning, but, as has been mentioned, you can try alternative methods of tuning. I've also had excellent results with Alpha-N (TPS) tuning. There is also the ITB method that is a blend of MAP & TPS. (MAP has better resolution at low RPMs and TPS better at higher RPMs)

regards,a
l

regards,
al
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Old 08-13-2018, 08:22 AM
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