odd question about SS props

This is going to sound really silly to ask.. but, recently I bought a stainless steel prop at garage sale (got it for $20 and couldn't pass it up). I'm surprised by the weight difference between an aluminum and a SS prop.

The odd question: Is it bad for an alpha 1 outdrive to have to hold and spin the weight of a SS prop versus an aluminum prop? Just seems like it would be harder to spin such a heavy prop and would put more pressure on the outdrive to turn it.

I'm sure it doesn't matter, but I had to ask..

Re: odd question about SS props

It is actually easier to spin a stainless prop even though it weighs more. What seems like a drastic difference in weight to you is not noticed by the engine.

Proof: you will see about 400 RPM more at full throttle from the stainless prop than the equivalent aluminum and usually a couple of MPH more. Stainless prop blades are thinner than aluminum and are more rigid. It takes less horsepower to physically spin the stainless prop through the water so more horsepower is available to drive the boat.

A similar difference existed in drag racing circles where some use a heavy flywheel and some use a light one. The theory is that while it takes more horsepower to accelerate the heavy flywheel, during shifts this horsepower is stored and engine speed drops less on the upshift, resulting in a lower E.T. Since a boat is not shifted, heavy versus light makes no difference and because the prop is easier to screw through the water, it will be accelerated faster than the aluminum prop anyway.

As far as damage control, if you hit something hard enough, you will bend a prop shaft whether the prop is stainless or alumimum. Anyway, this argument to me is similar to saying that a plastic bumper on a car will cause more damage to the auto, because of less protection, than a steel one if you hit something--sure, it will, but the object is not to go around hitting things.

As far as I am concerned the only downside to stainless is initial cost (new) and price for repairs--about twice that of aluminum.

Re: odd question about SS props

I'm sure it doesn't matter,

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