I just moved to a remote location that only has 91 octane. My car was dyno tuned for 94 octane and a base 91 tune was provided.
Details:
04 Cobra
Gen 2 Whipple 3.5 pulley at a max of 15 psi
Other typical mods are catback, TB, RAI, HE, etc
91 Octane
So I loaded the base 91 octane tune and dropped the timing back a bit and added some fuel and I will test the car until I am satisfied that the gas is okay here (note not many run 91 octane so it likely sits for a longer period of time).
Did a bit of datalogging with only my Aeroforce guages and noted that my timing was 20 degrees up top on 15 psi and my AFR is low 11's to high 10's.
I did some research and did not find as much information as I wanted to determine what is a safe and optimal timing # on 15psi at redline with an AFR of low 11's on 91 octane?
Seems to me this is in the upper range of typical / safe?
Thanks
Details:
04 Cobra
Gen 2 Whipple 3.5 pulley at a max of 15 psi
Other typical mods are catback, TB, RAI, HE, etc
91 Octane
So I loaded the base 91 octane tune and dropped the timing back a bit and added some fuel and I will test the car until I am satisfied that the gas is okay here (note not many run 91 octane so it likely sits for a longer period of time).
Did a bit of datalogging with only my Aeroforce guages and noted that my timing was 20 degrees up top on 15 psi and my AFR is low 11's to high 10's.
I did some research and did not find as much information as I wanted to determine what is a safe and optimal timing # on 15psi at redline with an AFR of low 11's on 91 octane?
Seems to me this is in the upper range of typical / safe?
Thanks
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