ORIGINAL: c-traxx
Is there a chance to change body of 1/8 scale buggy to a lets say a savage one? and what engine would you choose betwen the three (hobao, kyosho, ansmann)??
No, you can't use a truck body on a buggy, if you want a truck body, get a truggy instead of a buggy. Also, none of these companies you mention make engines, they rebadge other companies engines.
For good cheap engines, look at SH engines, GO engines, STS (are they still around?). How much do you want to spend?