[yjsjin]

Originally Posted by qubert

Using lower octane gas than rated can cause detonation (AKA Autoignition of fuel) what happens is that the temperature inside the cylinder will ignite the fuel mixture before the piston is ready, before the spark (Higher octane gasoline has a higher autoignition temp) This causes bad things for obvious reasons, and can often be heard as a pinging sound. Serious detonation will break your engine, again for obvious reasons -- 1 piston pushing left, one pushing right... something has to give.

All that being said, its not really a problem AFAIK to limp around on lower octane gas IF YOU GET STUCK. Don't romp on the throttle, or push it and you shouldn't have a problem.

thanks for the info!