FWTexas

I assume the factory tune is a bit rich but what is the sock air/fuel range on an LS3?

What is considered a safe A/F with a typical custom tune?

Any input would be helpful...thanks.

REVAK

Don't have info on the LS3, however the factory WOT a/f ratio on the LS2's run around 11.3 to 11.7 . Generally speaking 12.8 to 13.2 seems to make the most power on the dyno, 12.5 to 12.6 is safer for the street. I have heard that the LS3's run better a little richer than the LS's. I'm sure one of the forum tuners could give you more specific info.

Redline Motorsports

We have seen many LS3 cars do into the high 10's for power enrichment. At best there in the mid to high 11's.

You should target 12.5-12.7 as an "average".

Howard

FWTexas

Thank you, Sir.

kelp

Sorry late. Did AFR study. 13.2 best for me. Depends on your mods, try multiple dyno runs to be sure.

Oh and D/C the evap when you are tuning.

midgetracr

My LS3 liked an 11.5 AFR up till about 5500 RPM then transitioned to 12.5 above 6000. This was with 93 octane pump gas that included 10% ethanol and an LC-1 wbo2 sensor. Your results may and probably will vary.

'VETTE PHASE

If they are NA, they must be running a lot of ethanol. Surely you can't be seeing high 10s on gas.