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Woodsy · 03-02-2017, 03:36 PM

I have to disagree here guys....

1st... No single prop outdrive is going to match the holeshot and mid range performance of duo-prop design.

2nd... Going from an aluminum prop to a SST prop might net you 1-2 MPH top end with A LOT OF TESTING but there will be drawbacks. Think of propellers as gears... Everything is a compromise. You can gear it for max RPM and speed, but you lose holeshot. You can gear it for holeshot but you lose top end. In the end its always a compromise.

3rd... Shreddy mentioned his boat is a 94 and has an OMC drive. OMC went out of business in 98-99. They haven't been in business for 18 years. So his boat/motor combo is 23 years old. My guess is the engine probably has 800-900 hours (40 hours per year on average). The motor and outdrive are tired and not making peak HP/Torque. A mistake changing a prop could cause an outdrive or engine failure...

If I were Shreddy (and not ready to totally throw in the towel) I would figure out what prop originally came with the boat, and what do I currently have on the boat. Then I would go look for a similar pitch/rake/OD prop in SST. If you go to a four blade, drop 1" of pitch to start. Merc makes the hub kits so you can use a Merc prop on an OMC drive. This gives you tons of choices. But.... a new SST prop will run ya $450-$500 or so depending.

Woodsy

03-02-2017, 03:36 PM	#1
Woodsy Senior Member Join Date: May 2004 Location: Weirs Beach Posts: 1,967 Thanks: 80 Thanked 980 Times in 440 Posts	I have to disagree here guys.... 1st... No single prop outdrive is going to match the holeshot and mid range performance of duo-prop design. 2nd... Going from an aluminum prop to a SST prop might net you 1-2 MPH top end with A LOT OF TESTING but there will be drawbacks. Think of propellers as gears... Everything is a compromise. You can gear it for max RPM and speed, but you lose holeshot. You can gear it for holeshot but you lose top end. In the end its always a compromise. 3rd... Shreddy mentioned his boat is a 94 and has an OMC drive. OMC went out of business in 98-99. They haven't been in business for 18 years. So his boat/motor combo is 23 years old. My guess is the engine probably has 800-900 hours (40 hours per year on average). The motor and outdrive are tired and not making peak HP/Torque. A mistake changing a prop could cause an outdrive or engine failure... If I were Shreddy (and not ready to totally throw in the towel) I would figure out what prop originally came with the boat, and what do I currently have on the boat. Then I would go look for a similar pitch/rake/OD prop in SST. If you go to a four blade, drop 1" of pitch to start. Merc makes the hub kits so you can use a Merc prop on an OMC drive. This gives you tons of choices. But.... a new SST prop will run ya $450-$500 or so depending. Woodsy __________________ The only way to eliminate ignorant behavior is through education. You can't fix stupid.