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What does determine an engine top speed? Answered

I was asking myself what does determine the top speed on a gas motor like on a car( E.i why a lamborghini motor is faster than a normal mazda) so do you know what does determine an engine top speed?



Best Answer 8 years ago

The design of the motor determines the top speed or the max rpm it will achieve. It has to be balanced very well. It has to me engineered for strength but light weight. It helps to be a short stroke engine. The exhaust and intake has to be high flow. The valve springs have to be high pressure or the valves float and don't close completely. If you run a mazda at 8k rpm it won't last, but nascars that are built to run a high speed will do it all day. It helps that after every race they are rebuilt but that's another story. Motor cycle engines rev very high but they are usually multi cylindered and short stroke. Model airplane engines have very short stroke but will rev in the 20-25k range for the racing engines.

I think F1 racing engines can run at 20,000 RPM - 400 revs per SECOND ! They don't last terribly long in the scheme of things though.....

Yep. There are a lot of thing that I can't even imagine and 400 rps is one of them. Think about the stresses on the parts. The pistons start and stop 800 times per second.

Hey thx for your answer guys!