91 octain

If you dont and hit boost the conditions in a engine going over 100% VE make the air/fuel mix want to explode before the piston makes it to TDC. Not to mention the extra heat created by running a turbo, etc. Octane = resistance to burn. You "could" run low octane.... but your asking for a missing ring island or a hole in the head gasket.

OUCH...good point. Just wondering is all.

you can run a lower octane you just wont be getting the most of what your car can go. i've know plenty of idiots who ran 87 octane and it as fine. but you are soppose to run a higher octane.

Is that a stock car running boost with lower octane? If so thats an ecm that understands boost. The can handle protecting the engine from detonation alot better than one thats ment to be N/a. Run low octane on a car with a piggyback and watch what happens if your pushing anything other than 5psi. Not to mention stock boosted cars typically run lower compression and run rich anyway.

yeah, all they have is a fmu.