I have a 10mil serval running shearer sb in frames 39pwks 22cc domes 7deg timing and race fuel it is a monster in low to mid rpm but does not rev to the moon compared to a cub.. Off pipe it had a shit load of power and comes on hard has a decent hit "which I don't really like".
On the pavement it will blow tires off very easy even off pipe in the 1st 3 gears I would say I'm 330lbs and it has a 8in swinger thou.
I rode my buddy's 492 cheetah and my serval has more real low in the rpm range but the cheetah had less hit and way more topend .
But his is a 4mil where mine is a 10mil
Hope you find a setup that works for you