A turbo motor with a knock sensor may make more hp with premium, it will allow timing to advance slightly, and possible increase boost (if ecu allows that adjustment). Low octane can cause pre ignition, which may damage the turbo only if a piston comes apart and makes it out the exhaust!! High EGT can damage a turbo, as well as whats stated above..why am I rambling, guess I'm sick of work

 

Yes but the knock sensor works the same with what ever grade gasoline is in the car.It all works the same.I admit that premium will make the car run cleaner and possibly a little better.With the cost of high fuel prices it wont hurt the car being run on lower octane fuel.

 

Yes, I guess my rambling was only that you may make more hp with premium. I'm sure regular is fine by the ecu..