best A/F ratio for heads and cams??

[east_sidaz]

I got stage 1 heads and cams on my 99 mustang GT . I know on Forced induction applications the A/F ratio should be around 11.5 max to be on the safe side.
So what is a safe Ratio for my car??

 

[nickmckinney]

12.5-13:1 at WOT

 

[bhuff30]

Tuned for maximum power, you'd probably see an air fuel ratio around 12.9 to 13.1 across the band. You can go signficantly richer without a problem, but it will cost a few hp. I'm not sure where the 4.6 is most knock sensitive, but most likely, a well tuned car would have a lightly rich mixture (12.6ish) in the mid range, that leans out to 13:1 by red line.

 

[east_sidaz]

ok so if i tune the car to about 12- 12.5 across the band, i will be very safe, correct??

 

[SaleenGT2001]

yes, that will be safe

 

[2002BLGT]

slightly rich around 12.4-12.6 at 2000-2600 rpm will give more low end torque , but you want it to lean out to 13.0-13.2 for best higher RPM horsepower ....