27 Fever Prop/Drive Info
 

I had the luxury of doing some real run testing with my boat and thought I’d share the numbers. Lots of people (myself included) try to figure out what ratios work best with given props etc… This info is not all inclusive but this is what I had to work with. The drives are stock with stock x-dimension.

The boat is an 03 27’ Fountain single step with Raylar HO600 about half tank of fuel at any time. Kept adding small amounts while running. Recently had the bottom blue printed. Numbers from digital tach (SmartCraft SC500) I had about a 12 - 15 knot tail wind with very consistent 1 – 2 foot white caps. Running downwind of course and skipping across the chop.

1.65 Drive stock 32 RH Bravo I Four Blade:

3500 rpm cruz at 41 mph
5350 – 5400 at 82 mph

1.50 Drive stock 32 RH Bravo I Four Blade:

3500 rpm cruz at 47 mph
4820 rpm at 80mph

1.50 Drive stock 30 RH Bravo I Four Blade:

3500 rpm cruz at 49 mph
5000 – 5050 at 80 mph

The hands down winning configuration on this boat is a 1.65 gear set turning a labed 34. We’ve achieved 86+ with that setup at around 5200 – 5300 rpm.

If you were to cut the stock 32 down and run it on the 1.50 gear set it would get better but not nearly equal to the 34 setup.

Makes sense here. It is how Fountain gets the best speed out of the 35 EX 496 package, using the 1.65 drive and 32's. The only negative with that set up in the 35 is that it takes a country mile to get it there. You might have a better all around package with the 1.50 / 32 set up if you labbed the prop and pulled the r's back up there. How is the acceleration and throttle response with the 1.65 / 34 combo? Looking at your numbers the 30 Bravo set up with some lab work might work as well. I would try to get a labbed 30 and 32 then run those back to back. I'll take a super strong mid range to an extra one or two on the top end any day.

The tail wind is huge. I got 77 GPS w a tail wind once.

Now Labbed 28 75 gps was the best.no waves of wind.I had it labbed so I could get whole shot too. It planes off with trim tabs up and about 1/2 throttle easily and I can ski behind it easily as well.If you punch it w the tabs down. It literally jumps on plane.

It is like 5150 was about 72.. the every 100 rpms is about 1 mph.About 5400 is 75 and so on .
That is a non step 92 with around 6-700 hp. (more torque than HP). with1/2 fuel water skiis extra prop and all the tools and extra stuff for anything you need boating.Porta pottie full of fresh water etc.

A stock 26 bravo 1 was about 72.5 MPH at 5400

With a 1.5 bravo.

I think you got Quite a bit out 0f your rig to get 10 nmore MPH than me. The step is about 3. the botom of our rig is pretty wavey w bumps and a lot of big wave hits I guess. that must be a couple.

Yeah depends on what you like. All I care about is top speed period. There isn't enough left in the 32 or 30 to make that big of a difference for me personally. The 1.65/34 setup is the only way. I already knew this but wanted to play around with it and I figured someone down the road will benefit from this post. It's not numbers out of a sales catalog; it's the real deal.

I have also been told that 1.65 gears are "high altitude" but I know nothing about that.

Hey SD Fever...Anytime you are ready... Let me know if you really want to go for some top end some day.. This thing runs about 119 up top.. I feels like about 200 though.I have 2 seats for it...:D

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