I liked the sound in the video. Seemed like it moved that flat-bottom boat right along.

I hear ya...gotta start with a good baseline though, then amp it up. The fact of making turbine hp down the road gets me pumped...but, gotta stay focused and start simple.

Ed, if that little boat was flat bottomed, he would have done quite a few endos after pulling the big boat he was next to. That boat had some Vee or it would have simply swapped ends!

That sound reminds me of the jetski I built back in 2002. Only two rotors...but without a muffler, it sounded like it was powered by nitromethane...down right nasty.

lol rotor = Pissed off bee hive!

you keep talking about this " 6 rotor" like it actually exists. when mazda tried to race the 4 rotor in gtp it needed a muffler roughly the size of the entire side of the car and the heat generated would routinely light the car on fire... and these were the factory guys that actually knew what they were doing. when it came by on the straight at daytona it sounded like an f 16 at about 185 db. and they don't make enough torque to do anything at all. yes you can turbo it or supercharge it and make 300 hp at 8500 rpm... but at 3500 trying to get up on plane you are going to need rocket assist. and you better plan to have an oil cooler roughly the size of your swim platform.

its an interesting notion... and fun to talk about... but the practical application falls into the " what the hell are you thinking about " catagory. do some hard research about the thermodynamics and fuel efficiency of that motor. they are about the worst on the planet... reliable ? yes... nearly bullet proof. applicable to boats or trucks or farm equipment that need grunt ? no.

but its your time and money...

I keep hearing about budget. What is your budget for the turn-key solution? What is your projected height of this package? Shaft height must be very low, which means you will be gearing up the shaft height with a custom box capable of lots of torque if you plan on bravos. You may go straight out if you use surface drives. Xr drives will cost you about 10K each and surface drives are more. Are you thinking that you are going to extend your cockpit floor back to the transom without a step? The dyno idea is a good suggestion; however you will be spending many thousands for enough time to test your theories about endurance. I suggest you buy a beater direct drive boat, direct couple and run her hard for 40 hours to test out your predictions. Your new boat ain't no jet ski I am guessing 15,000#s fully dressed. Someone has probably powered up a 37 to say 650HP a side and do they go 70?

My boat is stated to be at 10,000 lbs with two big blocks. I don't think it unreasonable for 1200 hp to get it at around 70 mph. From what I understand, over 800 hp total gets it over 60 mph.

There is a budget or should I say, prohibitive financial direction. I can figure out to put different powerplants into whatever setup, but if someone tells me it is $4k per motor times four (outboards)...that math is simple and cannot be done. I have nearly four rotaries in my garage...probably end up picking up another 4 rotaries to complete the project. They average about $500-$1000 ea...but each one will be rebuilt at a cost of $500 each.

The biggest cost will be the coupling. No...don't think it has been done before, but then again, I'm guessing a nutty propulsion engineer has never been signed up to the task.

Muffler will be about 3-4 cubic feet each and fed with water...should quiet them nasty rotaries nicely :)

No coupling system needed. Just need to adapt a 454 flywheel or ringgear to the rotary counterbalancer, then build a billet adapter from the mercruiser bravo housing to the rotary engine. Straight forward.... Coupling the motors will be another interesting task...but nothing difficult. Just need compliant couplers and there are many to chose from.

rexx,
this is really exciting. a few thoughts: 1.) there is always the turndown pipe option for idling/low speed noise reduction. 2.) as a strategic excercise, reverse your chronology on engineering challenges; since it seems that you've got the bascic powerplant issues solved or have the ability to solve them, spend most all of your initial energy on the ancillary systems- cooling water delivery/pumps, hydraulic systems/steering, adequate electrical systems/charging, marinized fueld management/delivery and filtration, engine mounting, placement/ x dimension considerations, quality air delivery and backfire prevention. etc. etc.if you were to run into engineering or financial challenges you'd know it before you made the whole leap - keep us posted - jeff

Hmmmm...first stumbling block. I measured wrong. I can't get 3 two rotor motors installed as initially planned....short by about an inch or so if accessories are included.

Now what! Well, I can either supercharge 2 two rotors or revert back to the 454s. If I revert back to the 454s, about one foot of deck space will be lost on the longitudinal axis. Plenty of space to be had with the 454s and seats moved further aft and a storage area would be included of the would-be very short sundeck. So now the quandry, do I attempt to pull this off with rotaries or stick with BBCs and lose about one foot of deck space? The lazy side of me says stick with 454s...the crazy engineer side of me says go with two 2 rotor motors fed by roots type blowers. This will take more pondering for sure...it was a slam dunk with three 2 rotor N/A rotary motors.

I still don't understand how you are going to get a deck back to the transom, over the top of the rotary’s using the bravo o/d input shaft w/o a drop box.