Ive waided through magazines and forums etc and from what I can tell a .12 or .15 generally goes in a 1/10th car and .21 in 1/8th and .25/.26 big block go in trucks am I right?

Ive been looking at the ofna hyoer 8 port pull start (2 year warranty) its only $130 and develops 2.4hp
will this drop into the kyosho 7.5 or the mugen mrx3
The ofna's have pretty high compression therefore can have starting probs especially when new thats not a prob when breakin in id expect it but is it a thing that crops up to often compared to other engines.
any O.S. / novarossi recomendations? this seem to be race engines tho at a high price.

can any1 help[&o]