What should it run?
 

New to me 99 zt280 with 700hp what should the top end be on this boat?

Guessing low to mid 80's???

I have heard with an hp 500 they are 71-73 so I was thinking the same thing, low 80's..... Anyone else have experience with this hull and additional power, and If so what were your results?

Member Kelly O had a big power ZT 280. Shoot him a pm. I had a 99 with a 500 efi that ran 71gps.

I don't see his screen name pop up when I tried to pm him??? Anyone had 550,600,650hp, and what speeds were seen? Also what's props have you guys had luck with?

Try KellyO

Got it thanks!

Rob
Two of my friends have that boat with 502 procharged engines, they run in the 82-85mph, also there engines where dynoed @700hp

I bought the boat and am going for a water test and to pick up in a couple weeks. This boat has a 502 mag that was punched out to a 509 had a mild full roller cam installed (not sure which one yet) edelbrock rpm aluminum heads inco power flow exhaust, and a m-3 pro charger with the 5 pound pulley on it. He is claiming the boat is running 72-73 gps right now with a out of the box 28p bravo 1 four blade. The engine was built and run in this tune over the last 2 seasons and has been stone reliable, it currently has 115 hrs on it. He has has seen 78 on gps with a different labbed 29 blade. Anyways I guesstimate this engine in the 700hp range and it just seems like this should be a solid 80 mph boat all day. Boat has a bravo 1 drive with xr upper internals in it and stock lower. I thought maybe charger was weak and not making the boost it should, but he says boost gauge shows 4-5 pounds??? I too figured this setup should push this hull to at least 80 if not a little faster. Could it all be in the prop? What Rpm do these Efi 502 like to run at, he said it is seeing 5100 rpm's with the 28p bravo 1. It just doesn't seem to add up.........

Sorry 1.5 ratio in the drive also.