velocity2002

***lurk mode off***
I've got a 2002 Potato chip boat (Velocity 280) with a 496HO spinning a labbed 26 bravo one. The best gps speed is 74.3 mph 1/2 of fuel with the wife aboard and we were bouncing the rev limiter (puget sound area = cooler weather) the temp outside was maybe 60 degrees. I was told to try a labbed 28 bravo one (Scott from velocity). so I got one, I'm able to spin it about 4800-4950ish(damn near 5000) depending on the weather. With the labbed 28 (it's a pretty thick lab job) the best we've seen it 78.6 mph on a cold 56 degree november day. both day we had about 8-10 inch even wind chop. I run the 28 bravo most of the time unless we are loaded down. Meaning more than three poeple total. I must have a magical 496 Ho.. Or it could be that I have a thin chip...

***lurk mode on***

fountain27ho496

Wanna trade? I know.
That is a fast hull, velocity has always been 5-10mph faster than many others. I like that 28, wish I wasn't trapped in this one.John

Macklin

velocity, that is one fast 28 footer with stock power!

Indy, I'ld say I have a prop problem. Here is a pic of a properly labbed Bravo 28 sitting against the pitch block.

Macklin

Now here is a picture of one of my labbed 28's in the same pitch block.

velocity2002

I think I'm pretty lucky to get those number out of that set-up myself. Or Velocity just did a extra nice job on everything because it was one of the Miami boat show boats. But All the velocity's I've seen at the local dealership (7 total) have been really nice and put together very well and solid. Although the 280 that was on powerboat TV was sold by at the same place as mine. But I don't remember the number he was running.
I noticed the same thing when I took my labbed 26" bravo to get worked on. All the blades were at a diiferant pitch. They were able to true it up, re-balance it. clean up the edges after the summers running and Hopefully I'll have good luck with it and I'll take my 28" up for some more work.

Here is a separate question... How many of you think running 100-200 rpm's below max RPM on a full computer motor is bad??

doug hess

You can literally profile an engine's HP curve changing props. All other things being equal when a higher pitch lowers increases RPM and speed drop you have gone beyond max torque and HP. Drop the pitch to where speed goes down and you are below max HP. If you change prop designs it is another story.

Gofasts

Funny, I was just out today seeing what is wrong with my set up. I am a new boat builder "Triple000ught", the first boat is a 28.5' Triple000ught. All aluminum and weighs about 3000lbs with the 496HO in it, no interior etc. yet. It has an 8.5 beam and mild steps. I thought with the low weight I would run close to 80, I can only pull 72.6 with low fuel and 70.6 with almost full fuel. Kind of slow.. I am running 1.36 ratio and a stock 26P. I just got the Smartcraft hooked up and found out I am stuck at 4430rpm at WOT, 70mph. I noticed that I could pull 68 with only 4200rpm. I was thinking I need to go to a 24-25P?? I really don't know? I would think with the low weight I would be able to outrun the Velocity. Any ideas?? to see the boat goto www.gofasts.com search Triple000ught. thanks

Steet

Your prop size sounds okay, but you have to go to a 1.50 gear ratio to run this setup. I have tried 1.36's and they do not work well in a mild power boat. In my opinion, you should only use these when you run out of prop.
The 1.50 will give you better response and mid range and not lug the engine,
plus get the engine rpm up to the peak range.

articfriends

iTrader: (1)

Fountain27 (john),your still more than welcome to try my 28 that was worked to a 27 by hydromotive,Smitty

Escape Velocity

I've got a 496 Mag HO in a Velocity VR 1 and a 26" Bravo 1 runs 69.6 mph GPS at the rev limiter (5150). A 28" Bravo 1 only runs 67 GPS at 4800 rpm. This was within a half hour of each other, on a hot summer day and calm water. I think my mufflers (exhaust tips) are knocking a bit of stuffing out of the engine.