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seano
06-05-2000, 09:14 AM
In case anyone was interested in how things worked out with 28ss, we put her in the water this weekend and tried out a set of 24" 4 bladers(Bravo1's I think, I didn't look a the name on them?). Spinning the drives in, with 30 galllons of fuel and 3 200lb guys in the boat and no back seat or cabin, the boat ran 68mph on radar turning 5000 rpm. The power is a pair of 350 mag MPI, 300hp with Bravo I performance drives. We figure slip is around 11%, which ain't bad for a 6700lb v-bottom. I have to say, this is one great running boat, we raised the x-dimension 2" and could have gone at least another inch to the sky. It comes up on plane real nice, although it will break loose if you nail it.

I would love to squeeze another 2 mph to get to 70, so we ar gonna try a set of 25" 3 blade cleavers. Although I doubt these will work properly, I'm interested to see how they work. I'm actually trying to get a 50mph cruise at @3000-3500. I'm pretty close now, but as I said, I would really love to see a top speed 70.

We had quite a large pool down at the shop and I predicted 67mph---I was never so glad to lose!

This has been a 2 year project and I'll document it on my website if anyone is interested. I've got a bunch of pics which still need developing, so I'll keep you guys posted.

If anyone has any prop suggestions, I'm all ears http://206.150.187.82/ubb/smile.gif

Forrest
06-05-2000, 11:27 AM
Sounds great! How 'bout trying a pair of 25"p Mirage props? If you need a pair, let me know. I have a brand new set looking for a home. . . and the price is right!

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Forrest

seano
06-05-2000, 11:51 AM
Thanks Forrest, I know a little about props but I'm no expert. My feeling is that the 25 Cleavers we will try will provide stern lift...I had my buddy run the boat at WOT with the 24's 4 bladers while I sat on the chase boat and it looks like I get plenty of bow lift, so these may just work.

I am under the impression that generally speaking, 3 blades provide more top-end speed, while 4 blades cut down on speed, while providing the best out-of-the-hole acceleration and mid-range cruise. Am I correct in this assumption?

The Mirages you have are the round ear type, correct? If the Cleavers don't work properly, I'll be looking you up...what were you looking to get for those props?

Forrest
06-05-2000, 02:45 PM
I can let 'em both go for $500 plus UPS charges. Give those cleavers a try, you never know, they just may be the ticket.

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Forrest

Inevitable
06-08-2000, 10:15 AM
I am running a pair of 25 pitch Raptures on my Z-29, and they work great for the price. Started off with a pair of 23 pitch cleavers, not enough prop, too much RPMs.

seano
06-12-2000, 07:06 AM
Quick update on the prop dilema...tried the 25p cleavers this weekend...what a bear getting that thing on plane...heavy vibration and she kept breaking loose. Had to bring her up real easy. Lost at least 5mph on the cruise and didn't gain any top end(she threw some rooster tail though!). Turned 4900-5000rpm. It's too bad, those props had a real nice price! http://206.150.187.82/ubb/frown.gif

Anyway, it looks like I'm gonna have to spend the big bucks and get a pair of labbed Bravo1s. Theres'a aguy in Michigan I think who lab finishes them and can twist them a little more and take some cup out so I can get some more RPMs out of them($800 per prop). Does anyone know who that is?