[Fr. Frank]

Flats boat at 90+? Sure. Not too hard to do. Got one locally.
SeaCraft at 90+? Not without a complete redesign of the center deadrise toward the stern.

In 1985, I rigged a 20 MA for a lady lawyer with a Merc 225 that would go 65-66 or so after adding nosecone, jackplate, blueprinting the hull, etc.

We also rigged a 20 with a 3.4L Merc on a jackplate that we got to 73 mph after weeks of trials. It was flat out dangerous. The chine walk passing through 67-68 mph was extrmely violent, and required putting some down angle on the K-planes to overcome. It turned either a 28" cleaver or a 32" cleaver to achieve the same 73 mph. It just had different jackplate heights. The limitation was hullspeed.

I have ridden in a 23' Seavette with twin 235 'Rudes that would indicate 78 mph on the Airguide racing speedo. It was rock-stable at that speed. BTW, it would not get over 70 mph in flat water, it had to run in a pretty good chop to hit 78 indicated. Again, the limitation was hullspeed.

But there is always some nut who will strap a jet engine to a skateboard.

Locally, we have a physician from Tampa living in Homosassa who has a 16' Shypoke with a 2.4L Merc Bridgeport on a jackplate that will run an honest-to-radar 98 mph. In a race across Ozello bay, wherein both boats were also radared by a complicit Sheriff's Deputy, the 16' Shypoke positively smoked a 20' Talon picklefork running a 520 hp Mercruiser. The Talon owner had claimed a top speed of 108 mph. In the race, the Shypoke radared at 98 mph, the Talon at only 90.

It wasn't even close. The Shypoke just flew away from the Talon. We were in a chase boat that was a Formula 233 with twin 350 EFI Magnums, running our top speed of about 70 mph.

Let me say this about the Shypoke: it is a pure "Come-To-Jesus-Now" machine. I swear he was out of control half the time. But it surely did go fast.

So it can be done. But I think you have to be really stupid, or really young (and stupid). (Like I once was )