[05mustang_TT_charged]

I am data logging my car and Mass Air is reading 4.8 volts and the fuel injectors are 39# and showing 92% duty cycle. All I did was up the boost on a 2.8l Kenne Bell, The A/F Ratio is around 12.1-12.3 at WOT and just cruising it's about 15.6-16.8 average. I got the kit with 8 psi. and upped to 10 psi. and was told not to worry about it and the dyno is closed for another week or two. Could it be the tune or maxing stuff out. I was told the mass air was good for 535 rwhp and injector for 515 rwhp

[impetus]

i believe you need a new tune. 15.6-16.8 is way too lean. fuel pump seems to be keeping up ok (WOT).

i went to the Kenne Bell website and found this...

"you may be suprized to see the air fuel ratio is the same WITHOUT RE-TUNING, even with HP jumping from 401-469 and boost from 5.5-9.5 psi."

did you log any data @ 8 psi? who does your tunes?

[05mustang_TT_charged]

the tune came with the supercharger, the fuel pump cycled on and off and kept delta between 40-60 psi. i am waiting foe Shreve's Automotive to open back up to get the car custom tuned. Steve is one on the better tuners in South Louisiana. Never datalogged injector, mass air was 4.3 and fuel was about the same.