4g63t boat

77amc · Post by **77amc** » Mon Jun 29, 2009 8:10 am

Keep in mind that a 'craft' in water is ALWAYS under resistance. It's not like after you get rolling that it gets easier and stays that way.
I don't think that you will be able to shift it either for the pssshhaaasssii sound you want.
You would need plenty of torque at low speed. Just like those little thin boats you see in the South East Asion countries.

A friend has a small jet boat that he got at a police auction that I'd like to get the drive/running gear out of. It was confiscated from drug runners down the Mississippi, and suposedly a 'hopped up' rotax motor and impellers.
I'd like to adapt it to my 16 1/2ft fishing boat to get into the shallows and wouldn't have to worry about a prop with the youngins swimming around it.

Just my .02

E

77amc · Post by **77amc** » Mon Jul 06, 2009 4:19 pm

It's the torque and a different pitch prop.

citrus3000psi · Post by **citrus3000psi** » Wed Sep 02, 2009 9:29 am

If I was doing a boat setup it either be a 350 or a turboshaft

This guy has a few turbo boats he built.

http://www.turbokart.com/home.htm

kezark31 · Post by **kezark31** » Sat Sep 05, 2009 12:25 pm

the wooosh sound come from the throttle plates closing creating vaccum and opening the bov. shifting has nothing to do with the bov. i think a 4g boat would be pretty cool. i would go all motor though for a boat maybe some side drafts

crackerman · Post by **crackerman** » Thu Sep 10, 2009 12:48 am

what kind of rpm do you want to run? i have been seriously looking into the boat thing as well.

standard inboard/outboards will not take the constant 6000-7000 rpm for long periods you will want to throw at them.

jetboats however, will.

berkley jets require 120hp at 4300 rpm to push their jet drives, stainless impellers will take unlimited horsepower (hence the twin turbo'd big blocks you see in these things) the jacuzzi jets are similar in design and requirements, both have aftermarket ride plates, scoops and filtering grates(to keep small children out of the jet) available to make the boat faster.

craiglist will have jetboats ranging from 200 to 19,000 depending on size, quality, completeness and how old they are.

and its a great idea, unlimited supply of 50-85 dg water to cool aircharge, oil temps and closed system cooling temps is a great idea.