Chris Bacon wrote:

I wonder when petrol injection came in, then.... would it have been in
the 1920s? I was just saying that the concept is old - improvements in
manufacturing and materials make old ideas viable. There aren't very
many new ones!


It was certainly in use in some pre war aircraft engines...


You wouldn't be testing my knowledge, would you?
No, not at all.... would you regard the Wankel as a one-stroke, 1 1/2
stroke, 3-stroke, or four stroke, though? ( here - FWIW ).

I need some time to think about this. I may not be able to answer you.
I _did_ know, but my memory has probably let me down.

It's sort of a joke question, really... the answer is there, though!

I'd say its still a 4 stroke, in that the induction and firing cycles
are done in two volumetric compression expansion stages.

Depends on how you define 2- stroke/4 stroke.