ok.. the buggy is a good buggy.. dont get me wrong.. however.. there are things that are very poor on the car..
1. Shocks.. bend very easily
2. Diffs.. front- comes with only 2 planetary gears inside, aluminum ring gear, and the pinion gear is weak as well. rear- same as front. center- plastic spurgear, only 2 planetary gears
3. chassis braces. definitly need to get some of those
4. chassis- there is no notch out in the chassis for a newer motor. if you put a newer motor in your car.. the clutchbell rides on the chassis.. causing motor wear.. need to space the motor plates up for clearance.
5. the center dog bones are thinner.. bend pretty easy.
6. same with the front and rear dog bones
Do not get the K3 front diff.. get 2 K3 rear diffs.. alot of racers are getting rid of their LSD diffs for the standard diffs..
the buggy is a good buggy.. to get you going.. but you gotta put alot of money into it.
If you replace the motor.. you gotta get all new stuff.. new header, pipe, flywheel, clutchnut, bearings, shoes, clutchbell, motor mounts and plates.. alot of stuff just if you replace the motor..
This is all from experience..