AIR fuel readings ?

[Jim Vaccaro]

my gauge shows 12.7 at wide open throttle and on dyno tested at exhaust pipe it reads 12.9 :shrug:

which one is more accurate??

 

[SILV03MustangGT]

my gauge shows 12.7 at wide open throttle and on dyno tested at exhaust pipe it reads 12.9 :shrug:

which one is more accurate??

The gauge, tailpipe sniffers tend to be off a little.

 

[sloppymax]

I have seen some tailpipe sniffers read up to .5 too lean when cats are present. Maybe yours is only .2 leaner with the high flow cats in your x. Just my experience.