so i want to no wut i got so i looked up my casting numbers off my heads and it just said 85 to 88 truck oval port is that all it usually says or how do i no wut they are the stamp reads 14092360 also says a179

how would i figure out wut they really are

i wanna do 85 to 90 mph wut kinda heads would u think i would need,im pretty new but wanna learn more

I would start with the hull.
Is it safe at 90 mph?

wut about those 990 heads u got for sale?

There are some of the best cast iron heads that GM made.
A lot of guys prefer the steel heads.

Nothing wrong with aluminum.
I've got a set of CNC'd Dart heads that cost close to $3200.00

  Lupo your better off like Ron said and going with a different hull, i really i don't think you'll see very much change in performance throwing money into it,that hull wasn't designed for what your looking for   I'd start by finding a better hull something a bit lighter and a better bottom.

alrighty sounds  like i just gotta start a jet boat savings  account

  Your on the right track just keep asking question your doing good bro find a solid hull with a good pump and do a swap, River Dad here on the boards always pops up with great finds.....

thanks guys