Can you over-rev a rotary?

[atehrani]

I was in my friends 3rd gen RX-7 the other day and I noticed it does not seem to have rev-limiter. It just beeps, but it will just keep going. Then I thought about it and it kinda made sense, you really can't over-rev and damage a rotary motor. No vavles to bend, or rods...etc.

So assuming that the fuel pump can keep up and the water pump doesn't cavitate, and the turbos don't blow up how far can the motor go? Or am I completely wrong? :confused:

[00 scrub]

hahaha yes I know that buzzer noise, does your freind happen to have a 2nd gen rx-7/FC? The first time everyone hears that they think it's someone honking at them. As for your question I have no idea, mabye an apex seal will blow?

[yakkosmurf]

Yes, you can over-rev one. The engine parts are only balanced to certain tolerances. At higher rotation speeds you need tighter tolerances on your balancing. One your engine speed exceeds the tolerances, the motor will start to resonant and will eventually shake itself apart.

[atehrani]

But don't you think that rotarys come with tight tolerances? Besides balancing and blueprinting it wouldn't be too difficult. It only has 3 moving parts (excluding the turbos). The two rotors and the "crank".

[yakkosmurf]

You don't know much about the balancing of rotating parts do you?

[atehrani]

Obviously I don't, thats the reason why I posted the question. :rolleyes: