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Halo · 10-23-2006, 09:22 AM

I tried some 103 from Unocal after I got the SC installed because it had a grinding noise that I wondered (though seriously doubted) if it could be detonation. It didn't do anything noticeable with the butt dyno since the system is designed to run on 91. (Turns out the grinding noise is just gear lash and most of the Comptechs have it).

Anyway, the only theoretical problem with running race gas is that it is so high octane that it might not fully ignite during the combustion phase and some of it might still be igniting around the exhaust valve as it exits the chamber. I say theoretical since this probably doesn't happen with 103. The point of using 103 would only be if you are tuned to run very high compression and very lean and to prevent detonation. Since our cars are tuned to run on 91, higher octane won't help boost performance by itself.

10-23-2006, 09:22 AM	#4 (permalink)
Halo Senior Member Join Date: Mar 2004 Posts: 610	I tried some 103 from Unocal after I got the SC installed because it had a grinding noise that I wondered (though seriously doubted) if it could be detonation. It didn't do anything noticeable with the butt dyno since the system is designed to run on 91. (Turns out the grinding noise is just gear lash and most of the Comptechs have it). Anyway, the only theoretical problem with running race gas is that it is so high octane that it might not fully ignite during the combustion phase and some of it might still be igniting around the exhaust valve as it exits the chamber. I say theoretical since this probably doesn't happen with 103. The point of using 103 would only be if you are tuned to run very high compression and very lean and to prevent detonation. Since our cars are tuned to run on 91, higher octane won't help boost performance by itself.