In Reply to: Fuel posted by Steve Bullock on November 08, 2000 at 15:20:13:
As for fuel, there seems to be a fairly widespread misunderstanding of the relationship between octane rating and performance. The higher the octane rating, the slower burning the fuel -- this is desirable (and necessary) in high compression engines to prevent pre-ignition. Lower octane (more volatile) fuel in a high compression engine will tend to ignite far too easily and result in pre-ignition and/or detonation. Using a higher octane fuel than specified by the manufacturer will result in poorer fuel economy, lower power output, and an excessive drain on the wallet. Don't be mislead into believing high-octane always equals high-performance. That statement is true only when the engine is designed to burn high-octane fuel.
Just got a 1998 z3 for birthday. Wife handled whole deal?? After sitting for a few days it starts and runs rough for a minute or 2. Any ideas? i was thinking that the dealer may have filled up with 87 octane to save $$ on the deal. Could this be the problem? Filled up with 93 just too see but no miles driven yet. Pls help before i go to dealer and make a fool of myself.