Pro motor ?

[Steve Johnson]

with the high horsepower that modern snowmobile engines are making on gas these days, they would seem the way to go if you wanted to fab your own.
Any one messing around with these? I wonder what the down side would be.
Buddy Bear has a older rotax 570 that puts out close to 125 ponies on pump gas. looks like a bunch of room to improve from there

[MN1]

I'd like to see someone use one of these. Looks cool !!
http://www.aaenperformance.com/V4_racing_engine.asp
Mark N

[Bill Huson]

except for the extra wieght . . .

I've wondered how a multi-valve/cylinder 4-stroke would do racing. Motorcycle engines are cranking out serious power.

[nbass]

How much $

I'd like to see someone use one of these. Looks cool !!
http://www.aaenperformance.com/V4_racing_engine.asp
Mark N

Any idea what they cost?
Neil

[flaursen]

Does the mod class allow for experimental engines like the rotax or aaens in the inboard classes you certainly could play in the unlimtited hummm one would have to wonder

[Steve Johnson]

I suppose the size and weight might be some disadvantage.
How would they run sideways

[epugh66]

World wide, PRO, or "O class" rules are open. I can only imagine that if it were better, it would have been done. Over the years that I was envolved, I saw many "better ideas" come and go.

[flaursen]

I would flip that baby on edge and try to connect a mid tower and lower turn the carbs on edge I am sure they don't care what orientation they run no crank case oil and if it was in a inboard then connect to a drive and out to a alpha 1 or direct shaft like in a Cracker or Jersey
those engines are alot lighter than they use to be and back when they had a very limited horse power too my neighbor kid says they are getting 280 in his new thing 700 Polaris

Frank

[James Aderholdt]

Bob Solvie tried the 700 Polaris on a Pro Capsule Hydro back in the late 90's and didn't have much success.

[Dave M]

Yup

Lots of talk over on BRF on those snowmobile engines.

My theory is, if you could somehow implement the clutch system to go along with it, you would do okay in MOD. Without the clutch, the engines are slow pokes and can't get out of their own way when accelerating.

[26V]

Quote "the engines are slow pokes and can't get out of their own way when accelerating."

Did the motor reach top rpm? If they will run a drive system for a snowmobile they should have the punch to make a boat fly. Not sure how the drive is setup for a snowmobile but you may have to run a larger, shallower pitch prop to get good performace from the motor.

[kws]

LOL the road motor IE not the drag ones. put out 200 hp the drag one 215
if thats a slouch ill eat a prop (ground up of course )

[Charlie Pater]

My uncle tried a snowmobile engine several years ago. Had to pull the boat to get on plane because those motor had little torque at lower RPMs. The motor could not turn the prop fast enough to get up to the power band. Also, it was very difficult to keep the R's up in the turns. That's is why snowmobiles are clutched to engage (depending on setup) at 5,000 to 6,000 RPM. A snowmobile clutch could probably be installed in a boat to solve this problem. We have Yamaha 700s with Bender aftermarket equipment and they like to run at about 8,500 RPM while putting out 155 to 165 hp on pump gas. They are fun to ride. My son has a Yamaha Apex 1,000 cc 4 stroke with a supercharger installed. Depending on the blower drive setup and fuel, 250 to 300 hp can be achieved. Pump gas can be used for the 250 hp setup and race gas is required to the 300 hp setup.

[bh/]

Sovie

Bob Solvie tried the 700 Polaris on a Pro Capsule Hydro back in the late 90's and didn't have much success.

The Sovie's , [Ogdensburg,NY] are still at it, with some sucess, installing snow machine engines in small inboard hydros, ie; -the 1000/1500cc class which normally runs 4stroke Toyota motors. He ran at Long Sault [ON] last fall , showed good speed, and great sound, but did not finish. They run a motor with a broad torque curve, [aka 'low HP'], -as snow machines run an infinitely variable belt drive system, which allows the motor to operate in a very narrow torque band, and produce those extremely large HP values.
Not much use in an outboard, on a short course, where big grunt, not big smoke wins..

[pro350hydro]

Sanvigs did this with a Rotax 1000 cc with a Pro Capsule years ago. They fought many different problems with it, but when it ran it made huge power and was fast.