I have looked at a number of 272 Islanders with the 496 HO. Every person that has one has a different GPS top speed. Most guys have a 23 pitch 3 blade. Anyone out there have a 272 Islander with a 496 HO that can give me an idea of the top speed they can run and what prop you are running?

Mag HO 425 HP ? should run mid 60"s

I'm looking at 1998 272 Islander with the 496 HO and I too thought it would run in mid 60's. Guy said it would only run 54 on his gps. He claims boat was just checked out by mechanic and everything is working great. It's exactly what I am looking for and priced right, but it's 15 hours away. Don't want to drive that far to find out something is wrong with the boat. Any suggestions to possibly see why the disparity in speed?

54?? Wow, that's slower than my slow boat!! I would guess low to mid 60s as well. I had a friend with the old Baja 270 and 502 carb. Boat ran 70 on the speedo so mid 60s on gps most likely.

old 270 with 502 carb runnign mid 60's... Im thinking more like high 50's maybe 60.

Lots of wind drag on the islanders my guess is 60 mph on the nuts... with the 23

For comparison Steve's 232 islander with 454 mpi (310 or 320 hp) runs 59 top end on light load, with low gas

My 265 with 502 mag efi only runs 55-56 on gps. with normal/heavy load.

Both of our boats are turning mirage plus 23/ How ever I sent my prop out to bblades this passed winter.. See it that will help me out on top end.

For reference, my 252 with a mildly built 454 (400hp) would turn 62mph on GPS, with a labbed 23p 3 blade. That was with a half tank in mild chop.

I replied to your other thread as I have real world experience with the exact combo your looking at.
My 272 islander (496ho) turning a 23 P prop will run 62 mph all day long but I once hit 64 mph, maybe I was going downhill???? Lol
I tried a 25 P prop but the only thing that changed was my rpms, mph stayed the same but rpms dropped a couple of hundred.

I didn't have an islander but 1995 272 with carbed 454, stock it went 54 with Mirage Plus 23, after many mods I could get it to creep over 60 with a 25 Mirage plus. The only thing the 25+ did was lower the RPMs like Tom272Baja already posted.

I don't know where you are but if he's 15 hours away, that may mean he's in a state with a much higher altitude and that crushes performance numbers. Growing up drag racing in Colorado was an exercise in humility comparing numbers to the sea level guys

The boat is in New Orleans. Tom272Baja, what RPM's were you running at with each prop? Were you running a 3 blade and what brand? Is that GPS speed with the 62 or is that what the speedo said? Sorry for all the questions, but I really want this deal to go through with this boat, but the fact that is will only hit 54 makes me a little nervous.