Rodknock You are paying this guy for his PROFESSIONAL KNOWLEDGE and tuning your motor. He is asking you what you THINK???
12.5-12.8 A/F is where the most power will come from your motor under full WOT. Is your motor broken in??? If not,IMO I would go back to running a little richer at a 12.0-12.2 A/F. What exhaust exhaust is on the motor?? The car pipes or the dyno pipes? with or without mufflers. This all makes a big differents with tuning the motor. The motor dyno will get your setup in the ball park. To get the most power and performance out of your car you need to go to a chassic dyno. To twick the motor at the end a LM 1 tester will tell you at any rpm what the A/F readings are. What gas is the dyno shop running??? This will effect the numbers also. Take the motor and install it in the car. TOW it back to the dyno shop and have the A/F checked out with the exhaust on your car hooked up. This will save some money in the long run. An EGT reading also would not hurt. You want to talk call me 732-254-3536 in the evenings after 8:00pm est time. Rick L.