I like to give my new idea about rotary car engine?

Question

Who do I need to contact with?

Answer 1

Patent office.

Answer 2

If you want a second opinion on your design and don't want to post it here, consider asking a faculty member at a nearby university's engineering department.

If you know a mechanical engineer (or even a machinist or mechanic) you could also ask them what they thought.

Answer 3

Not to bust your bubble, but there is already a rotary car engine. It is called a wankle engine and it has been around for awhile now. The mazda R-x7 and R-x8 both have wankle engines in them. I think mazda has pretty much got the market (not much of one because of how finiky they are) for wankle engines.

But good that you are thinking ...