you will need to swap out the crankshaft for that sort of mod to work. I have 2 of these trucks, 1 is modded out with all blue aluminum everything and a DTX .18 with a steel spurgear and dual slipper assembly (too much engine for the 2 sp tranny, burns up the diff) I also have an OS .18 CV-r that is already set up to be used on the single speed tranny and has the output shaft you need also, it is just collecting dust and has great pop left and the recoil is in great shape also PM me if you are interested, I'll let it go cheap...