how much boost EVO GT640 should run?

 

I would not go over 1.3 bars in 3rd or 4th under full load... preferably with 100+ octane.
1.2 bars max on 93 octane.

 

Thank you for your fast replay. what about 91 octane. i called Mike and he said the GT640 has only one program and it adapt to low and high octane on the same boost. just add or remove timing based on knock.

 

The GT640 is the base platform for GT700, minus upgraded fuel system.
Timing is pulled on top end because lack of fuel supplied.
Run the best fuel you can, so knock sensor doesn't pull even more timing.
I run 93 min and 100 mostly in the summer.

 

what is a good AFR readings on these cars during WOT?

 

usually low to mid 12s and sometimes at the higher Rpms it will peak to high to 12s... it really depends on the tuner...

 

is this a safe AFR numbers. i was thinking more like 11.6 at peak torque and 12.00 at top ends.