RE: Differences between those 3 engines ?
perhaps I'm wrong for the name "cx21" is the one coming with the first 1/8th scale buggy of the same firm (not the first Hyper 7).
Thanx for you quick answer for the reliability of the 4port, I don't care if I loose 5mph...for a more reliable motor.
so its specs are good, that's nice.
Other advices ?