Wayne, you quoted number for the "trainer power system" Believe it or not, the TPS Evo and the Evo .46 are NOT the same engine. They are very close, but they have slightly different displacements. I haven't taken each apart to compare them, but I'm going to make a guess that the porting on the TPS is more conservitive to result in more torque and easier starting and idle handling, while the .46 is more aggressive, resulting in more power and higher peak RPM.