260SS with 6.2 Merc prop question.
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260SS with 6.2 Merc prop question.
I put this question out on another Formula boat forum but I thought that I might get some general information on OSO. Probably not many, if any, 260SS owners (not a go fast boat) here but here goes:
We bought our 260SS late in the season last year so only had one chance to take her out. The water conditions were very good for a high speed run. We had 3 people on board with a full tank of gas. All of us were 250 lbs plus the weight of the fuel plus the weight of all the added safety equipment. The boat topped out at 47 mph GPS and speedo. What concerns me is that we got as high as 5300 rpm. Max engine rating is 5200 rpm. Naturally, I backed off the rpms as soon as I saw that. To me, we had a pretty heavy but probably normal load so should I be considering increasing the pitch to 25?
I thought that it would be a good idea to see if the practical experience on this forum might provide an answer. I checked the math on a prop slip calculator and it came out to 14.1% slip. 5300 rpms, 2.2 gears, 24 pitch prop and 47 mph. If I go to a 25 pitch, with everything remaining the same, the rpms would be 5088 rpms which would be better, I believe. If any other 260SS owners can give their experiences, I would appreciate that.
We bought our 260SS late in the season last year so only had one chance to take her out. The water conditions were very good for a high speed run. We had 3 people on board with a full tank of gas. All of us were 250 lbs plus the weight of the fuel plus the weight of all the added safety equipment. The boat topped out at 47 mph GPS and speedo. What concerns me is that we got as high as 5300 rpm. Max engine rating is 5200 rpm. Naturally, I backed off the rpms as soon as I saw that. To me, we had a pretty heavy but probably normal load so should I be considering increasing the pitch to 25?
I thought that it would be a good idea to see if the practical experience on this forum might provide an answer. I checked the math on a prop slip calculator and it came out to 14.1% slip. 5300 rpms, 2.2 gears, 24 pitch prop and 47 mph. If I go to a 25 pitch, with everything remaining the same, the rpms would be 5088 rpms which would be better, I believe. If any other 260SS owners can give their experiences, I would appreciate that.
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Given the notorious inaccuracy of tachs (or is this a Smartcraft boat?), and that you were less than 2% over the RPM rating, I'd say that the boat was propped perfectly. Adding an inch of pitch is a 4% change, and will slow the boat out of the hole. Unless you run WOT all the time, I'd leave it. If you run WOT all the time, you need a bigger engine...
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Given the notorious inaccuracy of tachs (or is this a Smartcraft boat?), and that you were less than 2% over the RPM rating, I'd say that the boat was propped perfectly. Adding an inch of pitch is a 4% change, and will slow the boat out of the hole. Unless you run WOT all the time, I'd leave it. If you run WOT all the time, you need a bigger engine...
You're right, it probably isn't necessary to change the pitch. Probably won't run it flat out again and it does accelerate very well. Can't wait to see what fuel prices will be this season, won't be able to afford a flat out run. LOL.
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What year is the 260 and is it a Bravo 3 drive with the counter-rotating props? I don't know if this will help,but my 260 SS is an 05 with 496 mag and Bravo 3 with 26 pitch props. I consistently run 53 mph regardless of load and water condition. Been a few months so I don't recall the rpm at WOT, but it is right at the normal range for the 496 mag (not H.O).
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What year is the 260 and is it a Bravo 3 drive with the counter-rotating props? I don't know if this will help,but my 260 SS is an 05 with 496 mag and Bravo 3 with 26 pitch props. I consistently run 53 mph regardless of load and water condition. Been a few months so I don't recall the rpm at WOT, but it is right at the normal range for the 496 mag (not H.O).
I could probably increase my prop pitch but considering how very few times I'll go for top speed, I think C Spray is right, best to just leave well enough alone.
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Another thing to consider is the one test was late in the season and likely cool conditions for making a bit more horsepower. In the heat and humidity of the summer those 24 pitch props may be right on.
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Having a 260 myself, I agree with both Chuck's and 4mulas points. On a hot day out on Lake Mead with several large people and a lot of photography equipment on board (boat magazine shooting the SCOPE Lake Mead weekend), it took awhile longer to plane off. Another one of the drawbacks to owning one of those "outdated" Formulas ... they are always set up spot on and dialed in from the factory.
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Ok, so it does seem to be propped spot on.
I agree RedDog, Formula makes an incredible boat. I had a 40 plus year experienced boater on board. He likes Sea Rays but older not new Ray's. He carefully examined the Formula 260SS for quite some time. Sitting in the cabin on the Ultraleather he said, " I can sum this boat up in one word: Exquisite! Next time I decide to buy a boat I'm going to look at Formula!". That says it all!
I agree RedDog, Formula makes an incredible boat. I had a 40 plus year experienced boater on board. He likes Sea Rays but older not new Ray's. He carefully examined the Formula 260SS for quite some time. Sitting in the cabin on the Ultraleather he said, " I can sum this boat up in one word: Exquisite! Next time I decide to buy a boat I'm going to look at Formula!". That says it all!
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I've been addicted for a long time. Back when I was struggling thru residency on the east coast and had no money, my wise older brother living in Ft. Wayne took me down to the Formula plant in Decatur. I saw the 357 sitting in the factory showroom and I was hooked. It was inspiration to help get thru a tough residency and a very difficult time in my life. That was around 1988.
Before I moved to Vegas in 2008, I took a few friends and a graduating resident from my workplace in Ohio over to Formula for a factory tour and saw a 240 BR in the showroom. For a bowrider and small boat, it was incredibly well-made and laid out with room for a lot of people. After my move to Vegas, I found out how much I missed boating but didn't have storage available for my 382 and F350. The 260 SS was the perfect fit for boating out here, and I was fortunate to find a very nice, clean used one at Hilltop Marine in Kentucky.
I am planning to eventually bring the 382 out here once I have the funds to put up a storage building at my home out here.
Before I moved to Vegas in 2008, I took a few friends and a graduating resident from my workplace in Ohio over to Formula for a factory tour and saw a 240 BR in the showroom. For a bowrider and small boat, it was incredibly well-made and laid out with room for a lot of people. After my move to Vegas, I found out how much I missed boating but didn't have storage available for my 382 and F350. The 260 SS was the perfect fit for boating out here, and I was fortunate to find a very nice, clean used one at Hilltop Marine in Kentucky.
I am planning to eventually bring the 382 out here once I have the funds to put up a storage building at my home out here.