Does anyone have this engine? If so what RPM are they getting? I have a 91FX that peaks out an APC 14x6 at 11,800rpm or 11,500rpm smoky with a Performance Specalities UltraThrust exhaust.

Is the bolt pattern the same for the TT Pro 91? Will the Pro 91 respond instantly after 5-10 seconds of idle? Do high and low end mixture sync up well?

That is truly outstanding power if those numbers are correct[X(] I have a 91 FX that holds 11300 rpm on APC 14-6 using the Tower 75 muffler and a 60L carb. I can not imagine the Pro .91 will match your FX