Pat McPherson

Just for reference, on my 280 I run a stock 26p B1, 1.5 drive, 415HP/502. With an average load in the boat, 4600rpm@WOT, 68mph on the gps.

low_psi

Is the 1999 280 a true 28' boat or the 26' w/platform? I am not sure what year they changed.... If it is a true 28' than it's 4' larger than mine and only 40hp more. If yours is only a 26' hull it is still 2' larger, so I would say either way I am right on track by stepping up to a 28bravo or the 26 hydro on my 260 (24' hull w/375hp). I will know for sure later this week when I receive the hydro prop. Cold or not I am testing it!!!

Padraig

A 280 is approximately 26 feet long without the platform. In 1998 it was called a Velocity 26. The name was changed to Velocity 280 in 1999 because everyone thought a fountain 27 etc was longer. The 260 without platform is approximately 24 feet long.

My 280 (26) with a 502 mag came with a Hydro 26 pitch prop. It now has lightning headers, and a labbed prop and will hit 72 mph on a good day with some good chop.

rmfriday

if you have the 375hp 496 you need to find a good, clean bravo 1 26p. a nicked up prop is prob. a lot of your problem.
a 28p b1 with a 375hp is going to be very hard to plain. If i were you i would looka t your fuel system and try and find a clean 26p b1 or hydro 25p to test.

low_psi

We took the boat out with my buddies labbed and cupped 25p prop. Turns out it was a 14-1/2" 3 blade... Well as soon as the boat got up on plane, total prop blow out. She slipped so bad it fell off plane. So much for that. The weather was so nice, we turned around, put the boat back on the trailer long enuff to get the 26 Bravo back on it and went back out to enjoy the weather... The Hydro 26p that I bought should be in by Friday, so hopefully things will go a bit better...

low_psi

I ran it today with the Hydromotive Quad iV 26p. Definately the right prop for the boat. At 3200 RPM it was cruising at 40MPH. With the Bravo I 26p it would porpose at anything under 3500RPM and was running around 33-33 MPH @ 3200RPM. As expected I did see a lose of about 200 RPM. SO now I am only able to reach 42-4300RPM and saw a top speed of still around 60-62 (GPS). So I think there is still some sort of air/fuel gremlin I need to track down. There is little to no difference in the motor load and sound from 3/4-Full Throttle. I have checked to see that the throttle body is opening all the way. WHen I first got the boat the throttle body was terribly dirty, I was only able to clean the air horn, so I may take the throttle body off and clean it next. I am very happy with seeing speeds of 50-55MPH and am content. But knowing there is something not yet right will drive me crazy all summer long. After I clean the throttle body, I will run a fuel pressure gauge on it to verify proper fuel pressure and will also perform a compression test. One thing at a time, but making progress...

SAMDAHL76

what do your plugs look like? dry and light brown is what you are looking for, on the white side it is running lean not enough fuel, if they look wet and sooty probably running rich not enough spark to burning off all the fuel, if you run it lean long enough you can do damage to your engine, you probably have a fuel or spark issue, to realy see whats going on at wide open you kind of have to kill the engine at wide open then pull a plug and see what it looks like, you may have enough fuel and spark at idle wich will show a good burn, but a may show you something different where it starts lacking one or the other, i have done that in a blown mustang i had it showed me it was lean at wide open, never done it in a boat though but same idea

low_psi

All 8 plugs look perfect and consistant from cylinder to cylinder. They were all dry and have a light brown tint. Since I had them all out I put new plugs in yesterday. I really don't think running at WOT and shutting it off is a good idea unless I feel like swimming in my cockpit. That would most likely result in water coming over the back.

low_psi

There is nothing wrong with the motor, there is something wrong with the owner . I knew, when I got the boat, that there were barnicles on the bottom. Unfortunately, it has taken till now, and a posting in the general Q&A for me to put 2 & 2 together. I know that bottom paint scrubbs off speed. So would't it stand to reason that barnicles would scrub off more speed. I feel like the biggest jack a$$ right now. Anyway I posted a pic below, nice right? Anyway it is going in a rack later this week. I will get all the crap off of it then see how she runs. If it ran 62MPH like that, well.......................

low_psi

Got the barnacles acid washed off, boat immediately feels different. It picked up 5 mph at 3000rpm. Got it up to 65 (had plenty of throttle left) and got a lot of chine walk. I was real low on fuel so maybe some fuel will weight it down a little. If it continues to walk, I will switch back to the Bravo I prop and see how that does.