Jet drive
 

Has anyone converted a performance boat to a jet drive? Is it possible to just remove the lower unit and replace it with a hamilton or equivalent jet?

It has been done but the transom Angle has to be changed and the bottom needs some inlet changes some Jet Boat companys have inserts we did at TEAM SCARAB.
Mike J.

A few builders offered jet's on their boats as an alternative. Seen Donzi's 18's and sweet 16's, a Cig 20, small Scarabs, forsale, etc. Boston Whaler made a small 20 rage for short time with a jet.

I think that jets work best on small light weight applications; smaller, flat bottoms that air out easy, jets are a blast. Has to do with the "energy" absorbtion / torque / RPM range. Deeper V's, heavier boats torque and rpm needed is just not efficient to make them worthwhile. Hence why you dont see jets on the boats mentioned above much. The added work to fit a jet would'nt be worth it, if your talking about something like an 18 Donzi Classic, or other V bottom in that size range.

Actually jets are more associated as a safety feature right now rather than a performance option. They have the ability to advertise no prop, shallow water operation and such as that. I have been into the sea-doo jet boats for years. They make great toys, and hence I said toys. Nothing you'd want to stick on the water and say its a dependable water toy. Known for breakdowns all the time, but I will say they are the funnest toys on the water as long as you don't mind wrenching on them some. I had a speedster with the twin 110 HPs, a bunch of mods and it would GPS at about 63 MPH. There is one guy on the sea doo boat forum that has the new supercharged twins cutting 74 MPH top speeds. But keep in mind they aren't pushing much of a boat either. Sea doo did some with the Mercury sport jet engines, by far the best ones they ever made in my opinion. Basically a 240 HP mercury engine mated to a jet. Probably the best two out there are sea-doo and sugarsand, yamaha is in there as well. The rest were kinda underpowered. However, you are probably speaking in terms of adding like a berkley jet drive to a bigger performance engine. There is some out there, but rare also.