Stainless Prop

I am thinking about changing my OEM aluminum prop to stainless on my 2004 40HP fourstroke. Is this worth doing? Right now there is a 10 3/8 X 13 prop on the motor. Should I stay with the same size?

Thanks

Stainless certainly looks hot. The pros and cons as I've understood them (assuming I have understood them) are that stainless props flex less and therefore offer more bite on the water.

The cons of a more rigid material is that you no longer have that cushion afforded by the softer aluminum to help protect your driveline should you strike something really hard - like a shoal. I know there are other protection measures such as rubber hubs and shear pins so I don't know in the long run if this is an issue. Local wisdom in the shoal-strewn areas I boat in tend toward sticking with aluminum if think you're going to be finding bottom on a regular basis.

As for prop size (and pitch) I believe that's dictated by the need to have your engine turning within a certain RPM band at wide open throttle (WOT) and by changing these specs you are impacting the performance and health of your motor.

Dave, on a 40 you will not see much of a difference and it will be expensive. At best, you might see 1-2mph difference. Unless you are loaded with extra cash, put the money into fishing gear.