IROCThe5.7L

Is this normal? Thats what datamaster shows me.

sofakingdom

iTrader: (1)

That's a reasonable starting point for tuning, if not necessarily exact.

The low-load AFR will always need to be very close to 14.7; that being the stoichiometric mix for gasoline.

The WOT AFR will vary widely from one engine to another.

Typical well-built motors with good fuel distribution and low BSFC will usually want a WOT AFR in the 12.7-13.1 neighborhood. Occasionally even a little higher.

dimented24x7

iTrader: (2)

Probably the most important part is if your actually getting those AFRs. At part throttle, the stoich AFR is there to ensure that the AFR used in the fuel calculations meshes with the closed loop setpoints in the O2 PID loop. No 14.7:1, no closed loop. At WOT, those AFRs are only as right as the calibration. As far as the WOT AFR, 12.5 or so is good, but much leaner then that will probably melt the cat down due to too much O2 combined with excess fuel. If you dont have a cat, then it doesnt much matter. You can run whatever you want at WOT.

IROCThe5.7L

Thanks guys. I am on the stock tune. Under WOT, datamaster shows a AFR from 12.37 to 12.78.