Thread: What works best AFR's to aim for at different loads?

My 12.5:1 CR kept making power all the way up to 13. I would say 14.7 for cruising, then aim for 12.5 at the top of the load scale and blend it in between. If/when you get to the dyno you can dial it in further, but without knowing you dont want to go too lean.

when at WOT my car likes 14.3-14.7 before the VVL engages, after VVL engages i bring it to 13.1 untill just about redline, then i richen it out so i can shoot a mean fire ball at my shift

under light acceleration i aim for 14.3-14.7

when cruising i go for 14.7-15.4.

this is on a stock VE

When I had the sr16 pistons I found the car made more power at 12.1 vs 13.1. I heard Corey talk about that change when he bumped up his compression.

On pump gas or E85? I started out around 12.5 and moved toward 13 and it made more power. Next time i get to the dyno i will try it a little richer and see what happens.

pump gas.

For N/A motors, you want to be in the 13.0-14.0 range on WOT to gain the most HP. Some of you guys are running too rich, I run my sr20det at 11.8 WOT

I haven't taken a good look at this map on my tune in a long time, and I don't actually use it for O2 Feedback but it is a good representation of what I recommend. I've highlighted the N/A portion. Tuning for N/A and turbo IMO is exactly the same in this area. Ignore the boost sections, and the stuff at 8k RPM and higher is completely un-tuned so completely ignore that.

The 12.8-13.0 AFR at 100 kPa (WOT N/A) is dyno proven world-wide to provide best power. My engine when N/A on the dyno was no different. It is so certain, you can use this phenomenon to calibrate your O2 sensor by if you want. If you're seeing best power at any other reading, then either the O2 sensor is out of calibration (this happens all too often) or there could be a mechanical issue.