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View Full Version : Need help with picking the right prop for my 22ZX please help!!



Donzi22zx
05-10-2003, 10:56 PM
I modified my motor over the winter, New exhaust, MSD, and Hi flow flame arrestor. I have been trying to prop out my boat for the last 3 weeks, need some expert advise about what size and type of prop to go with. Here is the results of the props i have tried

24p BRAVO 1 69.3mph/gps 5400rpm/hit rev limiter
23p Mirage plus 69.5mph/gps 5400/hit rev limiter
25p Mirage plus 70.4mph/gps 4800rpm/ too low
25p Mirage plus Labbed 74.1mph/gps rpm?/ spun out of hole, slipped
26p Bravo 1 69.6mph/gps 4700rpm/ rpm too low, stern lift

The labbed Mirage Plus had best top speed but when comming on plane the boat would spin out and cavitate the prop and I never checked the rpm with that prop for sure. I need to be as close to the rev limiter with out hitting and to allow for future mods. If anyone can help me pick out the right prop please help, or call me at 1-302-249-1595. I am tired of trying different props and I like the 3blade over the 4blade, The 4blade makes me feel like I am out of control. Thanks Bill

Shanghied Again
05-10-2003, 11:04 PM
Bill, The problem is a 3 blade prop is going to be faster then a 4 blade prop on top end, The 4 blade prop will always give you better all around with a loss of a few off the top end, I don't like the way a 3 blade drags when you first take off. 26 pitch is to high the 24pitch 4 blade is the prop for your boat. Or a 25pitch 3Blade. They are the best! PS I have someone interested in your boat if you are still selling.

Donzi22zx
05-10-2003, 11:17 PM
The 24p Bravo worked well, but I was on the rev limiter, I might get Arizona speed & marine to recalibrate my ECU to rasie my rpm limit. All speeds are GPS and the rpm readings were done using a service tack.

Lil Grizz
05-11-2003, 10:11 PM
I would go with the 26 bravo over the 24. The speeds are similar but since the 26 is holding down the revs its going to give you more room to work with. That 24p Bravo is about at its limit unless you want to send it off to have some cup or maybe a little pitch added into it. I doubt that would be satisfactory since any future performance upgrades are going to require a bigger prop. I have spun a 24 bravo past 5400 and I can tell you this: it wont push the boat much faster(maybe 2mph at the most), it doesnt have enough bite at those speeds. Upping your rev-limit will only destroy your engine in a short time. Remember those big block magnums are stout but the internals WILL NOT live long at 5400. Going past that and basically the thing will start tearing crank and rod bearings, not to mention the harmonics that occur.

If you cant get the boat past 70 no matter what prop you put on I woulld go with the prop that got closest to the fastest speed of all without hitting the rev-limiter. With the exception of the labbed Mirage you are within a few tenths of each other prop. From what you are telling me I would guess that the ideal prop would be in the 25-26 inch range. Personally I dont care much for the way a three blade behaves on the ZX hull but its really up to you.
I would also look into some of the hydromotive 4 blade props, they slip through the water like a 3 blade but bite like a 4. The ZX loves to aerate the prop at high speed and when turning which is why a 3 blade cavitates and blows out so easy.

Donzi22zx
05-11-2003, 10:18 PM
Thanks lil Griz good info, I might try a 24 hydromotive, or a labbed 26p Bravo 1, i will keep you informed. By the way what set up do you have, prop, engine, mods, speed. Thanks