Hello, I have a 1.6l miata with what's supposedly an "FM2 race kit" installed. It boosts to 15psi easily but requires alot of timing retard to not knock at even 12psi on california's 91 octane.
Recently I've started filling up with Sunoco 100 octane race gas. This has eliminated all knocking with the boost set to 12psi and the ignition timing advanced 1-2 degrees past the FM defaults in zones 4 and 5. It's making great power, but as is usual with these things, I want more, especially given how much I'm paying for the race gas. My question is what are the safe limits of boost and ignition advance one can run when there's enough octane to not knock? When do the rods and/or pistons give up on the stock 1.6l? The FM manual recommends not exceeding 180kpa on a stock motor, so that's why I'm running 12psi... but even with the timing advanced from the FM defaults there is plenty of retard in zone 5 relative to zone 4 and of course zone 3. Any input based on experience is greatly appreciated. With the power levels it's making on 100 octane I'm afraid to just keep bumping the advance and wait for knock to start again. I imagine it will either knock hard and break something, or not knock and instead bend a rod because I've exceeded the mechanical limits of the stock bottom end. Regards, Vito Caputo _______________________________________________ Miatapower mailing list [email protected] http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower
