GoldDuster360
Petty Officer 2nd Class
- Joined
- Feb 2, 2015
- Messages
- 110
Hi guys, I value your inputs and experience, here is the current set up and performance:
16 ft Super sport hull (Sylvan Super Sportster in name only), Mercury 70hp 3cyl, 1983 model year. With all four of us, full fuel and gear it will do 34MPH (confirmed with GPS) at approximately 5750 rpm's.
The propeller is an unknown brand but is marked 10-3/8 X 13 which to me is the middle of the road-recommended prop when new 13 pitch aluminum prop. It is slightly beat up with a nick on each blade closest to the hub, some cupping damage on outer blades but super minor. No noticeable vibrations, I would say prop is performing 90% as new.
When motor is trimmed (manually unfortuanately) for best all around performance sometimes we experience excess ventilation or break away although only momentary at worst. Basically boat performs satisfactory, gets up on plane easy and can cruise in the 18-20 knot range (3750-4000).
What I was considering: Switching to stainless hoping for more aggressive cupping to avoid excessive breakaway and add a little durability as with manual tilt I sometimes run out of water when beaching or idling through the shallows(mostly sand), nothing that stalls the engine but even minor blade contact with aluminum can ruin your day. I have already read up on how it can make the shift action clunkier and cause prop chatter or you will break the gears In your lower unit when you hit a rock. Some folks opined you may need to change the pitch to account for less blade flex, etc. Really confusing when you start weeding through all the information not to mention who has the best blade design in the pitch I want, is rubex better than flo-torq for smoothness and strike protection?, a stern lifting or bow lifting propeller? etc..
The frugal side of me says get a quicksilver in the same pitch and toss the used one in the boat as a spare and forget about it, 34mph is decent with good cruiseability. The car crafter in me says let's wring out every bit of performance I can get, more power, less fuel consumption if possible and make it look good while doing it, who doesn't like the look of stainless steel
This is my first boat and while I think I have a good handle on it all Inputs would by greatly appreciated.
16 ft Super sport hull (Sylvan Super Sportster in name only), Mercury 70hp 3cyl, 1983 model year. With all four of us, full fuel and gear it will do 34MPH (confirmed with GPS) at approximately 5750 rpm's.
The propeller is an unknown brand but is marked 10-3/8 X 13 which to me is the middle of the road-recommended prop when new 13 pitch aluminum prop. It is slightly beat up with a nick on each blade closest to the hub, some cupping damage on outer blades but super minor. No noticeable vibrations, I would say prop is performing 90% as new.
When motor is trimmed (manually unfortuanately) for best all around performance sometimes we experience excess ventilation or break away although only momentary at worst. Basically boat performs satisfactory, gets up on plane easy and can cruise in the 18-20 knot range (3750-4000).
What I was considering: Switching to stainless hoping for more aggressive cupping to avoid excessive breakaway and add a little durability as with manual tilt I sometimes run out of water when beaching or idling through the shallows(mostly sand), nothing that stalls the engine but even minor blade contact with aluminum can ruin your day. I have already read up on how it can make the shift action clunkier and cause prop chatter or you will break the gears In your lower unit when you hit a rock. Some folks opined you may need to change the pitch to account for less blade flex, etc. Really confusing when you start weeding through all the information not to mention who has the best blade design in the pitch I want, is rubex better than flo-torq for smoothness and strike protection?, a stern lifting or bow lifting propeller? etc..
The frugal side of me says get a quicksilver in the same pitch and toss the used one in the boat as a spare and forget about it, 34mph is decent with good cruiseability. The car crafter in me says let's wring out every bit of performance I can get, more power, less fuel consumption if possible and make it look good while doing it, who doesn't like the look of stainless steel
This is my first boat and while I think I have a good handle on it all Inputs would by greatly appreciated.
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