1 MAIDEN AMERICA

stock 575SCi, stock Bravo 32s (cracked 4), 5350RPM (occasionaly hit rev limiter), 93 MPH GPS

stock 575SCi, labbed 15 5/8 Max 32s, 5100RPM, 90 MPH

intercooled 575SCi, labbed Max 32 (1 now cracked), 5350RPM, 95.8 MPH

intercooled/roller cam 575SCi (704HP@5350/714TQ@4300),
stock Bravo 34s, 94 MPH, all over limiters, tons of throttle left, came on plane excellent, felt like slippage all across the board

intercooled/roller 575SCi, 32P5X w/diffuser, 94 MPH, all over limiters, pounds of throttle left

intercooled/roller 575 SCi, stock Max 30s, 88 MPH, all over limiters, tons of throttle left, paid for

02 lightning, short stagger, 1.5:1 gears, 19.5 X dimension, stock lower XRs (IMCO X uppers), all numbers full of fuel (200gallons of 92) and people (appx 650#s)

What happened to the 34Bravos?
Opinions of overall performance numbers appreciated.

throttleup

I have run the slip on the props you have listed. YOur slip is better with the 5B props and faster too. However, the blade failure on the Maximus is troublesome. Keep in mind that Maximus props are round ears....they are not intended for surface piercing applications. So the higher your drives the greater the likelyhood for blade failure on a Maximus. I have seen 6 Maximus failures in the past 2 weeks from this exact thing ...in my opinion. So that being said your in a Fountain and we know historically that Fountains run very well and fast is semi-cleaver designs.

Have you run any semi-cleavers on your boat? If not I think you should consider doing so. I think you boat is set up for a
5B propeller configuration.

Julie

bbladesprops

HEHEHEHE, there's a pitch.

Of course the 5bl runs better numbers. Look at the X dimension.

And I'm sorry but the Maximus runs great on the surface and even better with minor tweaks.

1 cracked blade isn't uncommon with castings. Bravo drive 5blade propellers from Mercury, Hering or even TU have round ears to some extent. Adjusting or removing the trailing edge cupping in the correct places, affects the water holding issues and possible cracks or handling issues.

I don't care how the propellers are "finished". If they are poured castings from "Powertech", Precision Propeller, or the the best castings, Mercury Marine, they can have internal casting flaws that Hand finishing or CNC finishing can NOT protect. Using true billet material is the only way to prevent cating flaws. I know all the CNC finishing propeller people out ther did and still are experiencing multiple blade failures. It is common knowledge. Perfect investment casting and we'll all break less propellers. Truth be told.



4blade propellers have a longer time frame between load and unload. The blades don't have the area or thickness of the 5 blade propellers. With your X, the blades are struggling to hold together.

Stick with 5 blades and try all the props you can test.

My biased opinion, test some 34 Max's and tweak them to your needed recipe with the correct thickness curve.

1 MAIDEN AMERICA

I do like the Max's. Lost top end from the B32s but the midrange increased 5-7MPH and 2yrs before one cracked at the trailing edge. The B32's cracked at the trailing edge too, 4 in one summer(that's 1 month in Seattle). They were the style props that had the trailing edge machined perpendicular to the blade creating stress risers in my opinion. Are they much stronger when machined with the blade?
Why did the 34s suck so bad?

throttleup

The Bravo's, when used in a surfacing environment, can lead to blade failure. Some boats are tougher on props than others. That's the problem with lab finished props. They can't be made any thicker than the stock props. There are applications where a little extra thickness goes a long way. Add only 20% thickness and the strength goes up almost 50%. Likewise, a lab finished prop when thinned only 20% will lose about half it's strength.

Lab finished props don't have warranties. You buy a new one and toss a blade shortly afterwards and the typical response is "would you like to order a new one?".

Bravo 1 and Maximus props are not heat treated and do not go through a stregthening process. There are applications where they just won't hold up, especially when lab finished.

monstaaa

i set up an 03 38 with the same power. identical. the only difference i s it has i.t.s gimbals.

this boat runs 109.

and indeed it runs faster, better, safer with the clever style prop. this particular piece runs 33 hydro p5's.

i tried herrings, maxs, bravo 4's, hydro 4,5,and 6's, spinellis.

make no mistake i am a true fan of the maximus, but i bet you will get the best top end out of those hydros.

i agreee with julie.

especially since her opinion is open and mature instead of one of those snippy pot shot psots that you see WAY too often here on oso.