[Idaho]

Hey y'all...

Just purchased a cherry 94 Davanti.
Anyone else have one?
Was wondering what the best prop for skiing/boarding is?
Have a 350 Mag w/Merc......

Thanks,

Idaho

[mikeyt]

I'll go a little overboard here in hopes of answering any follow-up questions in advance.
What's on your boat now? Does it run within the engine's recommended rpm range when at wide open throttle? Is your tach accurate? Once you have the answers to those questions then you can decide what to do about your prop. If you are running a 21" pitch prop, dropping the pitch by 1" will increase your rpm's by 150-200 at WOT assuming the same number of blades on each prop. Dropping the pitch will also lower your top end but provide more low end acceleration. Increasing the pitch will act in reverse. In theory, a 21" - 3 blade aluminum will run very close to a 20" - 4 blade. The 4 blade will have more "bite" but also cost you maybe 1 mph at top end. Stainless props are "stiffer" than aluminum props & should gain you a little performance but at a higher $$ cost. They also generally cause more damage when an impact occurs. Composites props are okay as a back-up prop.

You can check your prop choice at the Mercruiser on-line prop selector site below: http://sites.mercurymarine.com/porta..._schema=PORTAL

[180diablo]

Hmmm looks like MikeyT nailed that one down.

If you multitask with your boat, a few different props of different blades or pitches would be a worthwhile item invest in. Lower pitch for lower end bite to grab the person out of the water and higher pitches for top end speed. As long as it is all running within the WOT rpm range of the engine/sterndrive of course.

For the costs, if I had to smack something I would rather it take out the $175 prop vs the $2500 lower end unit if I was running a SS prop.



btw - welcome to the forum

[WetWilly]

Welcome to the site Idaho,

mikeyt's right about the performance of the props and pitches. You need to assess your boating style or activities. For many years I ran a single prop for better bottom end for all around water sports. The top end was enough for me at the time.

As for Aluminum verses Stainless Steel, there's a lot of debate on this one! From my experience, there has been little difference with damage to the out drive with either prop. Excluding the Bravo 3 out drive, most single props have a insert in the prop hub that strips when a hard prop strike happens so damage to the out drive is minimized with ether material. The big difference is a SS prop will probably ding or just bend a blade or two where the Aluminum will most likely break parts or all of the blades off should it hit something. Again, this is relative to your speed and the object you hit. I would say, it depends on where you boat and if strikes are common there.

In 24 years, I've only had three known prop strikes with very little to no damage to the prop or out drive. (That included one grounding during low tide on a very high shoal which caused the out drive to kick up! Scared the beegeebees out of me!)

I remember hearing awhile back that Mercruser had a prop trial program where you went to participating dealers and they let you test several props on your boat to determine which one you like before you purchased it. Check around for prop dealers on line as well. Here’s one that has an exchange program: http://www.propmd.com/t-propellerexchange.aspx

Well good luck,
WetWilly