Bouncing (surging) Idle | AEM
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Last seen: 2 weeks 13 hours ago
Joined: 04/03/2020 - 06:58
Bouncing (surging) Idle

2nd post. Hope all is good. Newbie tuning the AEM.

All flex tables blended at 100% I only run E85. Timing at idle (vacuum) was around 10*, the higher I set the timing, the more the idle bounces. I'm assuming I need more fuel, what would be the best table to adjust if it is leaning out. Looking at running 30-36 degrees of timing.

Also, tip in at  any temp has a small hesitation but gets a little better with more timing.



Last seen: 11 hours 24 min ago
Joined: 06/06/2014 - 09:31
Last seen: 1 week 4 days ago
Joined: 09/14/2014 - 10:21
Idle timing is part of tuning

Idle timing is part of tuning. Some older 4 valve per cyl engines want more like 12-15 deg BTDC, while I've had some other engines with variable valve timing, zero overlap etc. want more like 5-6 deg BTDC for a stable idle. A lot of it has to do with cam timing, port flow, compression ratio, and combustion dynamics of the combustion chamber. 


Gotta test it out. 


Other stuff looks like general tuning.