Originally Posted by champi0n

It is similar to a piston engine only that is combusts fuel in 4 cycles. (intake, compression, combustion, exhaust)

for every full cycle of one rotar face, the shaft turns 3 times. On a piston engine a full cycle the shaft turns 2 times. So for the one rotor face to come back to its starting position there has been 3 combustions (including itself), or 6 combustions (ie 2 rotor) for 3 shaft rotations (1080 degrees).

For sake of easy math lets shoot for 6 shaft rotations (12 rotary combustions).

Assuming a 4 cylinder engine to do the 6 shaft rotations we would need the same 12 combustions. (each cylinder would have 3 full combustion cycles since we have 2 rotations for each cycle, 2x3 = 6 rotations)

Assuming a 2.6L (650cc per cylinder) vs the 650cc per rotar, they have both used the same volume and combustion cycles to achieve the same shaft rotation.

While shaft revolutions and number of combustions should stay the same for each type of engine, the change would be in the cycles themselves. While one rotar face would have to do 2,000 full rotations, the piston would have to do 3,000 in order to achieve the same result.

Or maybe i just ate too many mushrooms and im talking out of my ***?

Originally Posted by DemonRX-8

I think we have a winner! IMO the closest piston engine comparison to the 1.3L rotary would be an over-square (larger bore than stroke) 2.6L 4 cylinder.

Originally Posted by MazdaManiac

So, you want to say the Renesis is 1300 ml?
Don't forget that we are measuring air, not liquid.