Advantage 20.5 open bows

[lynn]

what are some other owners top speeds and what kind of mods does it take to see 70+ mine is 62 mph turning a B american turbin 5100 rpm :idea:

[lynn]

come on guys i need help!

[SmokinLowriderSS]

Morehorsepoweritis.
According to JPCalc, you need about another 100 HP, with no other changes.
Motor upgrades or nitrous. How fa$t do you want to spend, er, go? :)

[Taylorman]

Is this the green and grey Advantage? You were at the bikini photo shoot right? What pump and engine do you have?

[lynn]

it is a 454 stock 330hp american turbin B impeller and yes i was at photo shoot.

[Taylorman]

You may try an A impeller. Stock engine may benefit from the larger impeller.

[Cas]

The 20.5 Advantage is the same hull as the 21" Tahiti super cruiser......same mold. I'm pretty sure the boat you have is heavier than the 21' Tahiti so you will probably need to work on reducing the wetted surface. Since there isn't really a fix all for all boats you're going to enter the testing zone.
You're probably looking at trying a droop/ride plate, maybe some cav plates, and/or a different loader.

[lynn]

have loader, snoot, tried an A impellar 4700 rpms was all i could get max speed 58.5 tried a ride plate and shim kit the boat did not like it we then took it back off the guy who did all my pump work said i might see 65-68 with more horsepower just trying to find someone who has had more experiance with these boats as i am from texas and cannot find anyone else near me to ask questions before i spend a lot of money, would like to find some california guys with knowledge of what it takes to get one of these to 70 mph.

[advantage21]

I don't have an open bow but i am running 60 in a closed bow 40gals of gas and 3 people. If you don't have a place diverter invest in one cause the bottom runs extremely wet and you will see a difference with it. My engine is about 450hp and i am turning an american turbine b impeller at 4900 rpms also with a shoe,ride plate and droop snoot.

[lynn]

have a diverter, sounds like 70 may be impossible with this hull since you have 450hp and closed bow and only see 60mph maybe someone else has ideas.
:idea:

[Jetmugg]

Add HP. If the boat is set up decently, and the pump is tight, you simpy need more HP to run faster. If you could make it spin about 5400 rpm, with about 450-500 HP at that RPM, you should hit your number.
I believe that engine has the "peanut port" heads. Those are probably the limiting factor to making big HP increases. More compression, better heads, bigger cam, and you are there. Maybe spend $2K to get there.
My 2 cents.
SteveM.

[lynn]

now thats what i need info Thanks