If that motor ain't hurt, that thing won't last long they are good motors. You don't see many in 25" either. Ferm is right on about the transom. I would add that the rest of the hull be up to the task as well. While the 300 ProMax may not have the same service life as a 250EFI, they aren't that bad. Same 3.0L displacement and intake as the 250EFI with slightly higher port mapping, exhaust chest, tuner and different electronics. It was 2001 when Mercury started calling them the 300x and they changed the intake and used chrome bores (which require a re-ring @ 250 hrs). The 300 PM should put you into the high 60's IMO. I still don't know what will happen after 63 MPH. I would suggest you to ease into those speeds. It should get interesting.
The 20v does start to chine walk at 60 plus. It is a sickness.
BTW- That motor will use over 30GPH @ WOT.
|