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.

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... ;)

Not Smartcraft but Livorsi gauges. I didn't realize that tachs could be inaccurate, from past experience usually the speedo gauge is not dependable but, oddly the speedo was spot on compared to the GPS.

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.

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).

It's a 2008 with Bravo 3. In the accompanying link the 260SS boat test has the 496HO doing 54 GPS. In that boat, there isn't a lot of difference in performance, as propped, between the 496's since they both hit the 4400-4600 rpm limit and produce the same speed. http://www.usboattest.com/test/548/2...la-260-ss.html

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.

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.

Hmm, never thought of that. Very good point!

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. :)

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'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.

RedDog, you've got the best combination of having 2 boats. Hard to imagine a more versatile combo than a 382 and a 260SS!

I consider myself very fortunate to have the ability to do this. Only thing possibly better would be to have a matching 400 SS in the line-up like the one on the left in this photo.

Hematite,
I've got the same package as you in my 2006 260 and I top off at 48.6 mph @ 4900 rpm with full fuel and 2 on board.
It's not fast but it's the perfect boat for what I like to do.

A thing you could consider, is to stay with the same pitch and run the 3+4 combo if you are currently running the 3+3. If you are @ 5300 you are on the high side and possibly a bit out of breath. You are posting the fuel prices as a concern, the 3+4 will give you better milage, and drop you from 5300 to about 5100-5150. I would also be very surpriced if they hurt your time to plane. You can always contact your local prop pusher and see if you can try a set. If not, Bblades have a test program with 45$ price for 15 days of testing. Should you decide to purchase the prop, the 45$ will be deducted from the prop price.

A.O., Thanks for the suggestion about the BBlades trial program! I didn't realize that is available. Yes, the boat now has the 3/3 combo. Hmm, that 4/3 combo could have some merit, I didn't realize that there is also a mpg improvement. That never hurts since this boat will be at 30mph cruising the majority of the time that I own it.

I realize I am resurrecting an old thread, but It seems that I have just joined the Formula family.
We just bought a 2005 Formula 260 BR.
The boat came from a lake just north of Charlotte NC. It only has the 300hp 350 Mag-Bravo 3 so I wasn't expecting much, but I thought it would do better than 40mph?
Problem was, the wife loved the boat, so we made the deal anyway.
So, the boat is home, a good cleaning, a little maintenance, a full load of fuel, aaaaaaand 40mph.
My question is, how much faster is the same boat with the 496?
This boat has a thru-hull water pickup, which I'm sure cost 1-2mph, but dayum.
Does anyone else have this boat with the 350? What are the real numbers with this boat w-496?
We got a decent deal on the boat, so I may be in the market for a 496 Mag HO, with smartcraft.
Gawd I love boats... ( rolling eyes )

I had a 2002 260 SS closed bow with a 496 HO that I sold last year. It would run 52 - 54 on GPS depending on conditions and load. Great boat!

Why on earth would it have a thru-hull water pickup? Boat should run 45 - 47 MPH with the 350 MAG. What RPM at WOT? .

As stated above, what is your max rpm? What props are on it now?

Full of fuel, 38.6 MPH @ 4500 RPM
Previous owner had the hull water intake installed. Story I got was, "to avoid seaweed intake into the drive".
I have this little voice in the back of my head saying "previous owner melted an impeller once and this was the "fix" from a shop somewhere to prevent a repeat"

Not sure what pitch props are on it. I'm sure they are original.

I'd ditch that external pickup. You are 500 RPM down where you should be.

I would love to, but then concerned about the glass / repair to fill the hole. I realize the drag issue here, but seems like a dramatic speed loss for relatively minimal drag.

Not saying the pickup is the main culprit, just saying I'd ditch it nonetheless. I would not be concerned abut the hull repair. Should be easy for a quality shop.

What did they do to the LWP on the drive? Plug the holes? Or is it still scooping up all that water and directing it to...?

Need gear ratio and prop set pitch. 3 x 3's or 4 x 3?

Good point-point taken concerning the drive intake. When I get back to the boat, I'll look for prop numbers.

Just wondering if the drive is still taking in water, and that water is not being pulled into the engine for cooling and then expelled, has that become a source of drag somehow?