Should I leave it Stock?

jau126 said
No room to do a motor swap right now and the 273 seems healthy. If it does ever die I will drop a bigger cub motor into it but for now the 273 is sufficient.

I am SLAP happy with my 64 with the stock 170. It's an absolute hoot to drive. Were it not for the worn main bearings, I'd be leaving it alone.