First mod: PPE Headers... +35WHP

alecnet · 01-29-2012, 07:19 PM

Looking at the AFR curve below his TQ/HP curve and you see that those two dips low in the RPM range correlate to the car first running rich then overcompensating and leaning out before stabilizing at a nice consistent ~12.7 for the rest of the rev range. Most likely a little more tuning would straighten this out.

Interesting to note that this header seems to only really make a difference above ~6500rpm or so. I would bet that the rest of the gains come primarily from leaning out the excessively rich stock mixture. AFRs of 11.8-12 would be great....if the car was turbo charged. Granted, I'm brand new to 370Z's and the VQ engines, but when tuning L series engines in older Z's, ~13-13.5 usually returns the best gains on NA cars. For my turbo L28ET i shoot for AFR's of about 12.5 for low boost and 12 or so for higher boost and higher up in the rev range.

Are all 370Z coming out of the factory with WOT AFRs around 12? If so my first investment is definitely a decent tune to lean that out.

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01-29-2012, 07:19 PM	#34 (permalink)
alecnet Base Member Join Date: Jan 2012 Location: Midland, TX Posts: 19 Drives: 2010 PG 370Z 6mt Rep Power: 15	Looking at the AFR curve below his TQ/HP curve and you see that those two dips low in the RPM range correlate to the car first running rich then overcompensating and leaning out before stabilizing at a nice consistent ~12.7 for the rest of the rev range. Most likely a little more tuning would straighten this out. Interesting to note that this header seems to only really make a difference above ~6500rpm or so. I would bet that the rest of the gains come primarily from leaning out the excessively rich stock mixture. AFRs of 11.8-12 would be great....if the car was turbo charged. Granted, I'm brand new to 370Z's and the VQ engines, but when tuning L series engines in older Z's, ~13-13.5 usually returns the best gains on NA cars. For my turbo L28ET i shoot for AFR's of about 12.5 for low boost and 12 or so for higher boost and higher up in the rev range. Are all 370Z coming out of the factory with WOT AFRs around 12? If so my first investment is definitely a decent tune to lean that out.