Croceye

I got an Air/Fuel meter installed. I'm curious what's "normal" on a stock engine. I get 14,6-15 when on cruise sontrol and at WOT it goes down to 11,3 on 2nd gear on high rpm. On 3rd it's even a bit lower at high rpm. I think its a bit low, what do you guys think? Maybe the sensor could be off "scale" a bit?!

65sohc

That sounds correct. During closed loop, ie. part throttle when the engine is controlled by the O2 sensors, AFR always oscillates on either side of 14.7. Mustangs run quite rich at WOT. Most of the power that one gains with a tune is by leaning the full throttle mixture to between 12.5 and 13.0. Do you have a wideband O2 sensor or just a meter that reads off the stock sensor. Only widebands are capable of giving accurate WOT numbers and even then some brands are more accurate than others.

Croceye

I got a Autometer Sport-Comp Wideband.
So theretically I should have more power if I go WOT minus just a little bit? If I do that, example WOT = 11,8, and I back of a little bit it tries to maintain 14,7. I can't say I notice any difference though. Could it be bad to do hard accelerations but not going WOT?

DarkFireGT

The stock tunes on these things suck. My first run on the dyno my AFR dipped down to about 10.5, and the second run, it went below 9.

tom281

Agreed, the stock tune stinks.... get a tuner and tune from Brenspeed when you can. For now though that sounds about right IMO.

Croceye

I belive it will be sorted when I put the Whipple on and upload the VMP tune.