My original thought was very simple.

A thinned down SSM#6 propeller only gets about 0.040 to 0.070" ground down in key areas to make a big difference in speed.

A Bravo propeller is only like 0.125 thick and a SSM#6 is nearly 0.500" thick in places.

An outboard propeller is no thicker than a Bravo for the most part. So it would stand to reason that IF it could hook up, the outboard propellers would be substantially faster than a SSM#6 propeller and the hub would be small enough that it would work for a Surface Drive.

Now, an outboard has little camber to the blades, they are limited in diameter (from Mercury) to 15.25" and they have a small amount of blade area in comparison to a SSM#6. Recipe for failure but one never learns if they are not willing to spend the $$ and try.

So if there was a propeller that shared a some of the characteristics of the SSM#6 blade area but substantially thinner, it would be a great combination. I do not know how many cycles it would last for but it would be a fast propeller.

They would not be advisable for higher hp, but with a 525 Merc it would be a good propeller.

Sounds like a winter project for me.

Matt

I just read an article in an old Hot Boat mag where a guy is running a single 588ci n/a motor making approx 680HP. The boat was a 28 foot cole running a bravo XR with a 17.25 X 27 mercury racing prop at 88.6 MPH. The boat weighed 5200LBS. Did not say whether 4 or 5 blade but thts some pretty darn good numbers. If he's spinning 5600 on a 1.5 ratio am I correct that he only has 6 percent slip??. It got me thinking! I just went on BAM's site to see the price of a prop. My 30 foot Infinity (Canopied version of the Challenger DDC) used to be run with this style prop on a pulse drive, over 90MPH the boat became a handful to drive but the boat was alot faster than it is now with the Bravo XR. I'm running the same A-class spec motor with the bravo as with the pulse drive. I ran the boat split bullet (no bow lift and a alot of bow steer with a Bravo 1 26"), dropped it 2 inches, didn't get any better does not respond to positive trim at all. The bottom of my boat is absolutely straight, no hooks, no rockers What's everyones thoughts on running a high X with a large dia merc cleaver on a Bravo. I know the cleaver will give much stern lift but if the diameter allows + trim to lift the bow shouldn't this work???

My first thought for that prop on a bravo drive is lets say BOOOOM. Boom is spanish means scap metal!
My X Was 2 Below With A Bravo Drive 15.25 4 Blade Slip=14%
Then X 1 Below Speedmaster Drive 16.5 - 4 Blade Slip=15%
Then X 1 Below Speedmaster Drive 18 - 3 Blade Slip=21%
Then X 1 Below Speedmaster Drive 17 - 3 Blade Slip=22%
Higher X,s Need More Blades To Have Better Slip Numbers If You Ask Me. Next Is A 5 Or 6 Blade Who Has A Single Left Around 34p