1) I didn't start a new thread, I searched and brought up the official one.
2) It's the same engine family type which has similiar layout to a 13B NA engine
3) The both have 6PI but since I don't have a renesis in front of me I can't exactly take out my measurin' stick and see if it works.
4) It was answered lickity split by Kevin, and that's all I needed to know.

Thanks Kevin.

 

technically yes, but its not a good idea.

the eccentric shaft actually helps counterweight the rotors (believe it or not!), so by switching to an RX-8 shaft, additional counterweighting becomes neccesary due to decreased weight. the problem is you end up ADDING weight to compensate, and this added weight is on the regular counterweights, so its further from the point of rotation than the stock e-shaft weight was, so you end up with an ultimately heavier rotating assembly.

NOW, if you use a full RX-8 rotating assembly you'd be okay, but you'd need to machine the apex seal grooves to accept the taller FC/FD seals to handle the peripheral port exhaust, and the cost of a full RX-8 rotating assembly PLUS custom machining really makes it not worth it.