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#80: 02-05-2014, 08:29 PM
Avcs 10*
covertrussian's Avatar
Title: MPG Tuner
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Location: VA
Car: '05 LGT, '12 OBP, '00 G20+T
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Little tune update, had a 1k mile trip this weekend and got to play with the tune a little bit. Main thing I wanted to see is if filling the AVCS map hole would improve or reduce gas mileage. In short, AVCS control the intake cam advance/retard based on oil pressure, by giving advance to the intake cam, you can increase the valve overlap.


Generally speaking on restrictive turbo setups, you don't want too much overlap because it causes reversion. But at low throttle your back pressure is much less, thus overlap might be able to help you out. First map shows the "emissions" hole in the map at cruising speeds on the highway, second is me filling that hole up.

AVCS at 10*, fixing the emissions hole

I expected gas mileage loss due to fresh charge contamination from overlap/possible reversion. But results were otherwise, bone stock I got 24.60mpg (which has been about my average highway MPG lately). After filling the AVCS hole, I got 26.14mpg! I know 1.5mpg is not much to brag home about, but on this car I will take every MPG I can grab. Keep in mind this is actual MPG, not gauge MPG which is -5% to 15% inaccurate!

Last edited by covertrussian; 08-06-2014 at 08:03 PM..
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FJuan (02-06-2014)