buddy of mine just bougght a 1999 baja h2x with a 502 mag mpi and a 23 m+ prop. he was told it will run 85 mph but thats according to the speedo. any guesses on what true gps speed should be with this boat?

With a 23" prop, I'd say 66 on gps. No way 85...

Maybe 70. +1 on the no way anywhere near 80.

X2...lets get wet!

Friend of mine has a H2X with a 496HO and he sees right at 68ish on GPS depending on load. 80+..no way.

+1

Even 70 is rather impossible with the stock 502. With a labbed prop and right setup 68-69ish. A 25OL is a 65 mph boat with a 496HO. A little heavier but also a bit more efficient. So more or less the same.

That thing will need a 600sci to run 85. Even at 70 slip would have to be around 5% @ 5100. 85 @ 5100 rpms -15% There it is again, the magical negative slip. I want that in my life

I ran with one with a 502, he claimed he had some work in it but we ran neck and neck, best EVER on mine was 71.6 gps, so he had to be maxed out around 65-66...

My buddy had a 2000 H2X Boss with a 502, he claims 70mph GPS.

-Rob

Gotta love those "happy" speedometers. A buddy of mine just bought a 25ish Cobalt cuddy with 454 Mag MPI running stock exhaust thru the Bravo 3. The guy selling the boat claimed it would run 70 MPH. Yeah, right, and I have some prime swampland I'd like to sell...

My 1999 H2x had a 454mag in it and I hit 70gps with it one time by myself light load on a cool evening. Would run 67-68 without a problem. Not sure but I think it had a 25 mirage?, its been a while....502 boat should get to 70 real speed. I though the 496ho boats were around 72? Mine ran real well, fast 21 degree hull but not so good in the 3 footers......

My 253 with a 502 spun a 25 mirage to 5000rpms so im sure that h2x being much lighter is propped wrong, should have a 25 not a 23. By the way I used to see 75 on the speedo.......