lets just say that subaru HIGHLY RECOMMENDS high octane for a wrx. All TURBO cars should use nothing less then 91.

 

Octane is directly related to the amount an engine pings. The lower the octane, the faster it will burn. The higher the octane, the slower it will burn. This makes it less 'explosive' and less likely to burn uncontrollably.

Richard

 

Another misconception about detonation is it doesn't always happen when your running lean. You could be pig rich all the way through the RPM band and detonate like crazy. If the cylinder is reaching max cylinder pressure when the crank, rod and piston are right at or slightly before TDC then you get a cylinder pressure that will normally double. So it could go from 2,000 psi to around 4,000 psi. That extra pressure has to go somewhere so it will end up trying to beat the crank out of the bottom of the engine or the head off the top. Or just blowing headgaskets. Too wide of a plug gap can cause detonation. A weak coil can also cause detonation.

About cooling charge pipes, a little trick I always did was go buy one of those cheap windshield visors that are like the aluminum foil look that only cost about $2.00, and just cut it to fit the pipes and wrap them and zip tie them onto the charge pipes. Always worked like a charm. The way I would describe detonation would be it sounds like something is loose and ratling under the hood. Hope the helps.

 

Would you guys suggest going with new plugs on a turbo set up? If so what kind...

Keep all the info coming its a great help.

 

LOVE the idea of the windshield visors. I ended up making a decenly clean looking setup, but if I did that man, my friends would laugh even more... lol.

 

Yeah we used to have people laugh at us for using it too till they saw our cars on the dyno. 97 Civic DX non-VTEC, with a T3, 340lph pump, FMU, with Rx-7 Turbo II Intercooler sitting on top of the engine(the car had a ram air hood so the cooler actually fit), put down 316 HP. And we wrapped the pipes in the sun visor material. Not too many people laughed after that. Look at alot of Indy cars and other track cars and see how they wrap pipes and hoses. Basically the same thing. It reflects heat.

About plugs to hinder off detonation, it's usually a good idea to run a colder plug and a little bit shorter gap.