cams (kinda pricey)
jet kit (if its custom its gonna cost ya)
ive seen a katana handle a 30 shot ( dont know if i would go more)
and go 6 up in the back and 4 down in the front your top speed will be 50 but you could do sweet wheelies (no really 1 down in the front )
other than that i think your underestamating the power it would still get ya up to like 80 or 90 prolly if you want more than you need a bigger motor period