Cody,

I'm not sure I understand your comment but turning an 11x6 at 13K+ rpm on a 45 is well doable. In fact, a well tuned, piped, plugged and fueled YS 45 FR can turn a 10x9 in excess of 15K. So yes, everyone did use those engines and some, speed and classic folks mostly, still do.

The YS 45 is the class benchmark in my opinion and can do better than a Rossi 45, Jett 50 and even approach the thrust of a 55 (Webra, OS). Compared to engines such as a stock muffled OS 46 AX, the YS is in a class of its own.

This e-conversion discussion was really about getting a little over a horsepower out of the setup as far as I'm concerned. The 1 bhp power output figure equates to a decent bushed 40 in my mind (e.g., K&B 40).

David