PQ website advertise low 80's with 496HO's?
I've read 75-78 on that forum with 1999-2001?? Did they make changes to the hull lately? Or are their numbers way too optimistic?

My 99 had 500hps in it and it wouldn't run that,,,,sounds pretty optimistic to me.
That is just my opinion though

I have seen a 300 Revenge run in the high 70's and break 80 when it was brand new with twin 496.
80+ sounds unrealistic for that boat with 496. Maybe with 525 or bigger.

My '02 Vyper w/ 496's would run 80-81 w/ labbed 30P props. W/ stock props it would run 78ish.

Vyper340's '02 boat ran 80 w/ stock props.

My buddy's 300 revenge w/496s spins stock 28p bravos and run high 70s at 4700-4800
He has touched 80-81 when the boat was brand new with 26p bravo spinning 5000-5200
Does the Vyper have a faster or more efficient hull?

You have to realize some of these speeds are in salt vs fresh water. Salt could be worth 3 MPH?