Very interesting Ed, so what r we looking 4 in performance wise with this bi metal sleeve and the new crank as well ? Yours original BRB set was placed into Mark engine and i was getting similar lap time with 16 % and 25 % nitro. Hence with the latest crank and sleeve...where would the engine benefit from ?

P.s any more news or test results with crank or sleeve....email me as racing is soon around the corner !!!

Philip