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Old Aug 4, 2012 | 04:41 PM
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LS1T56FTW's Avatar
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Default Lean Spikes

Hi Guys,

To make a long story short, I recently installed a 228/232 cam with PRC 5.3 heads on my car. We have dialed in the VE and MAF, and around 3000 and 4000 at 37% throttle, the car goes VERY lean (20.0+ AFR for a split second) and the car stumbles hard, then comes back into decent AFR at around 3200ish and then does the same thing around 3800-4000ish. Any ideas on what could be missing from a tuning standpoint. Prior to tuning the car, it would not "stumble" like it is right now (but no idea on where the fueling was).

Any ideas what the issue could be?

Thanks.
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Old Aug 4, 2012 | 04:43 PM
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Post the tune. Interested in seeing the MAF curve and VE table. Got any log files to post?
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Old Aug 4, 2012 | 04:46 PM
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I will send this to my tuner and see if he can post anything up.

FYI the car has a Racetronix 255 fuel pump with rewire and 42# Bosch injectors.

The last scan we just did he should have a few times where it happened.
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