Next Question, "flywheels"

[boatman4021]

Is there any reason why you can't use an automatic flex plate instead of the heavy standard trans flywheel? I know from back in my drag racing days, the stick guys would run super heavy flywheels to keep the rpm's up when dropping the clutch, which also made for nice wheel stands. But, it takes more power to get them turning. With a boat, you don't have the option of mashing the throttle before you drop the clutch. Seems like using the lighter flex plate would be cheap hp and the only strain it ever see's is the starter. Any thoughts?

 

[Gimme Fuel]

Im not sure that the engine coupler would bolt up. But it might. On the flipside, you dont want the engine to bog down fast when hitting a wave. With the sustained torque and rpm a marine motor turns, i would stick with the large flywheel. The heavy weight also keeps motor from dieing when shifting gears also.

 

[boatman4021]

Coupler shouldn't be a problem, it bolts to the crankshaft through the same holes in flywheel.

 

[Gimme Fuel]

Ahh, thats my bravo mentality kicking in. Those couplers bolt to the flywhel.

 

[Jetmate]

That is all I have ever run on my Jet Drive. Flex plate works fine. Don't see why an out drive would not bolt up also.

 

[RNGRDVE]

What drive package is he running. I replaced the coupler in my '90 sea ray with Alpha One and it bolted to the flywheel.

 

[ezstriper]

the bravo one bolts to the clutch pressure plate holes, not the flywheel bolts, now you might be able to drill the auto flexplate and get it to work..sure somebody tried it..don't think you would gain anything from it +...you could try a light alum flywheel would do the same, still not sure what gain you would see...

 

[boatman4021]

the bravo one bolts to the clutch pressure plate holes, not the flywheel bolts, now you might be able to drill the auto flexplate and get it to work..sure somebody tried it..don't think you would gain anything from it +...you could try a light alum flywheel would do the same, still not sure what gain you would see...

Rotating weight kills horse power!

 

[ezstriper]

thats not true, will not effect power, will allow to rev quicker, but a heavy flywheel keeps RPMs up with enerchia and a lighter ones allows it to fall off quickly..

 

[atc250r]

Yup. Will make motor slower to rev up and down but won't alter the hp numbers.

 

[Fuelblender]

You need the heavy fly wheel, believe me

 

[jazzy]

Fountain got busted in factory class running aluminum flywheels a few years ago. So there must be some advantage.

 

[Gimme Fuel]

Lighter flywheel gives faster acceleration in racing. But they dont store as much energy for when boat enters a big wave and drags rpm down. Also, can make shifting gears around docks difficult due to less stored energy to be released when going from neutral to gear.

 

[fox88gt]

Good point there about docking. When you are idling, shifting into gear could possibly stall the engine without a heavier flywheel to keep the idle rpm up. That creates a possibly dangerous situation, approaching a dock or seawall without power to maneuver.

I could see a lightweight flywheel being an advantage as far as the boat's center of gravity is concerned. Not to mention, anything that can make the boat lighter is going to be a big advantage. However, faster acceleration wouldn't be the primary advantage in my opinion.

If the manufactures could get away with a light flexplate, I think they already would have. It would be a MASSIVE cost savings. A flexplate is nothing but stamped steel with a ring gear and a half dozen holes. A flywheel must be cast, machined, balanced, drilled, and have a ring gear installed.

An outdrive goes through unbelievable stresses when it exits and re-enters the water at speed. The shock loads on the drivetrain aren't that much different from picking up the drive axle of your car or truck at freeway speed, lifting it 3 feet in the air, then dropping it to the ground while going 60 mph.

I'll take the beefy flywheel anyday just for durability sake.

 

[Troy Boy]

I would be concerned about the drive shaft engagement to the coupler …The flex plate is not as thick as the standard flywheel….could wear out the coupler splines quick. Just my opinion

 

[ezstriper]

there's a guy on OSO doing a LS swap and going to try a aluminum flywheel...it going to come down to HP vs weight...personally I do not think it would be worth much at all, may even be a neg at times..just my .02