If you are just out and about bashing and practicing, then I guess its okay. The TRX engines does lack turbo cuts like the .18TZ has, but dnt worry, Dadders will cut at least 2 or 3 turbocuts into the crank in a full engine mod.

As for buying a different mount, all Traxxas stok RTRs have universal small block mounts. What I mean is that a .18TZ or TM, or any other small block SG shaft for that matter, will bolt straight onto the mount without any modifications needed.

You vehicles, is it a 4-Tec? With engines as large and powerful as the .18TZ/TM or your TRX3.3, gear as high as you can go to reduce the torque at the wheels. This will help accleration times in that you are less prone to break the wheels free of the road and drifting. As a result, you top end speed will be increased as well! Traxxas design and build their vehicles to be lighter than HPI vehicles; this is an advantage when accelerating!