In Reply to: Overrev problems posted by tbbmwm3 on June 19, 2000 at 06:03:52:
Most of the time when one speaks of an "interference" engine, they are referring to an engine that if the timing belt fails the valves will make contact with the pistons and do damage.
If a BMW engine is over-revved there could be contact with the valves and pistons causing damage. I quess this could be called "interference" but it is caused by driver error, not by an engine part failure as would be the case with a failed timing belt.
BMW's have protection against over-revving the engine while the engine is increasing rpm on acceleration with the rev-limiter but no protection against over-revving if too low of a gear is chosen while downshifting.
: Just a thought. Are these overrev problems common to only M3s or any BMW with a manual transmission? Do they all have "interference" engines?
: Thanks in advance.