I have a labbed Bravo 1 P28. The prop shop remarked it "27" when it was labbed. I had them do additional modifications to this prop to provide an additional 200rpm. They did not change the "27" marking but I do not know for sure what its true pitch is. Knowledgeable prop people state that the Bravo 28P is actually a 27 pitch prop. I mention all this because the true pitch of the prop is of course a key component in calculating slip value. Using 27 as my prop's true pitch the slip is 14.5%.

What nose cone did you use?

I used a pointy cone from "Leading Edge" for LWP Bravos. I got the rec from Teague Marine's sales staff. They also helped with installation advice. Cheapest $/mph I ever got.

I would call Teague marine and discuss which style cone, pointy or crescent is best for your setup if you really want to try one.

I believe that in the high 80's certain boat/drive setups cause the pressure wave on the front of the bullet of the drive to start pushing water away from the prop. Hence the high slip. In my case, 28 pitch, 30 pitch, 30 labbed props did not change my speed much after my power upgrade. All props had high slip. Once I put nose cones on and tried the same props again the results were more predictable. The 28 had high rpm, the 30's had lower rpm, etc.

My boat may be unique with respect to nose cones. I have a friend with an old 30' raceboat with same HP that runs 94 with the non labbed 30 pitch props at 10% slip with stock bravo lowers so I really believe that the benefit is boat/setup dependent. Also, the owner of BF site has the same model boat I do and runs a tad faster than me with slightly more HP with stock lowers so go figure. I would make sure you have a accurate figure for slip and work from there.

I also believe that the varying opinions that you will generate with nose cone threads on this board are due to the boat/setup variability since it is evidently hard to duplicate the results boat to boat.

Good info ThunderStruck! Thanks.

Bill

A friend had a twin engine cat with Bravos and nose cones. While he was getting one of the drives repaired he used a Bravo without a nose cone. Starting at ~85 mph the side without the nose cone started slipping more than the other side. At 90 mph there was a 300- 400 rpm difference between the two to keep the boat running straight.

Now that is a dramatic comparison and clear to me that if at 85mph or below don't bother. This just confirms the general rule of thumb that 90 is when you really can benefit.