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Lineleader
04-14-2006, 05:48 PM
I did a search on the subject and found info listed all over the place.

I replaced my stock RH TRS drive with a LH rebuilt TRS drive (fingers crossed)

I use to run a SS cleaver style 3 blade. It took a while to get out of the hole, but was a high speed ride near the top in.

I actually would prefer a quicker hole shot. Should I go with a 4 blade?

What pitch, size, blade count do you suggest?

It has a 454, 330 hp.

LL

onesubdrvr
04-14-2006, 06:03 PM
I did a search on the subject and found info listed all over the place.
I replaced my stock RH TRS drive with a LH rebuilt TRS drive (fingers crossed)
I used to run a SS cleaver style 3 blade. It took a while to get out of the hole, but was a high speed ride near the top in.
I actually would prefer a quicker hole shot. Should I go with a 4 blade?
What pitch, size, blade count do you suggest?
It has a 454, 330 hp.
LL
What's the gear ratio?

(if it's around 1.5:1), I'd recommend a 4 blade in the area of a 20" pitch, the 22" Turbo on my 21' Ragazza with a 350 +/- hp SB turned 4500rpm. My engine makes top HP at 5500, so I was going to go down to like a 20". Anyway, hull weight / etc. should be pretty comprable. The Bravo I prop I ran was out of the hole like a rocket, but spun the hub insert, and never really got a chance to give it good testing. Then I replaced the drive, and changed my ratio to 1.43:1, now the 22 is a little much prop.

Wayne

BUIZILLA
04-14-2006, 06:17 PM
I would try a stock Bravo LH 4 blade 22", good diameter, good blade rake. I think you'll be pretty happy with this one..

JH

Pismo
04-14-2006, 07:58 PM
The GT is such a cool boat. The first Donzi I knew well and fell in love with. Is the drivers seat on the left? if so then a LH drive is perfect. Shag carpet? Air horn on the deck? The 3 blade merc cleaver was such a fun prop, no bottom end but great, fast, loose top end, no reverse either, could make great tails. A GT with a 454, a TRS, and a cleaver, what a beautiful classic setup, but modern times call I guess.... Anyhow, the new props are far superior. The new props will have less slip, esp the 4 blades so you may have to drop pitch some. The Mirage Plus and the Bravo 1 are the current masters with good reason. You must have a 21 or 23 cleaver now so try a 21/23 MPlus or a 22 Bravo 1. A labbed 24" Bravo 1 might be perfect and would help the porpoise. I am not sure you really need a four blade tho, not a lot of weight or hp. Ebay, less than $200 for a non-labbed Mplus and you can always resell it for the same price. Good luck, enjoy the classic.