Complete repowering of a brick
#171
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From: KY
AllDodge, you might consider looking for an XR propset. 4 blade forward, 3 blade rear. They are not elephant ear props like the 3 x 3's. I put a set on my heavy 26' runabout and hole shot is significantly improved. Cruise RPM dropped close to 200 RPM for same speed. Lost a MPH or two on top end but who cares, it is a runabout. I went from 26" 3 x3 to 25" XR 4 x 3.
#172
I had to birddog eBay for over a year to find a nice set at a reasonable price. Turns out I got a set of test props from Cobalt. Guy said they used them on just a couple boats. $600 for the set. Looked brand new.
#174
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From: KY
#175
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From: Jersey Shore
The Bravo 2 not only has a bigger diameter prop but the lower housing is larger and sets the propshaft and prop deeper into the water which is why I think it seemed to work well on boats like ours.
Bravo 2

Bravo 3

Since I did my repower and new transom assembly and new drive i went for what was new figuring newer design B3 would be better than the B2 because they are on all the new boats. I would love to find a nice newer if not new B2 lower and be able to do the comparison. I use to be able to trim my boat to the moon with the 2 and old power. I use to get 39mph gps @ 4200 RPM spinning a 17 3/4 21p aluminum prop After the repower I had a very best of 48mph gps @ 4800 RPM with 24p 4x3 props. For some reason or another most likely due to weight I have only seen 46 this summer but the fact it sounds like the props are cavitating and I can't go into aggressive turns like I use to with the B2 makes me believe maybe the boat still has a bit left on the table with the drive. By no means was i looking for a rocket ship but my goal was simple 50mph WOT and high 30s cruise. I am a little shy on both but very close.
It is interesting reading your journey and your results. You definitely put some time into it and a lot money! It is nice to throw some ideas back and forth with a fellow Formula owner who has worked on similar

Obv mine is the station wagon on the right....

https://youtu.be/5dxUveatyWM
Bravo 2

Bravo 3

Since I did my repower and new transom assembly and new drive i went for what was new figuring newer design B3 would be better than the B2 because they are on all the new boats. I would love to find a nice newer if not new B2 lower and be able to do the comparison. I use to be able to trim my boat to the moon with the 2 and old power. I use to get 39mph gps @ 4200 RPM spinning a 17 3/4 21p aluminum prop After the repower I had a very best of 48mph gps @ 4800 RPM with 24p 4x3 props. For some reason or another most likely due to weight I have only seen 46 this summer but the fact it sounds like the props are cavitating and I can't go into aggressive turns like I use to with the B2 makes me believe maybe the boat still has a bit left on the table with the drive. By no means was i looking for a rocket ship but my goal was simple 50mph WOT and high 30s cruise. I am a little shy on both but very close.
It is interesting reading your journey and your results. You definitely put some time into it and a lot money! It is nice to throw some ideas back and forth with a fellow Formula owner who has worked on similar

Obv mine is the station wagon on the right....

https://youtu.be/5dxUveatyWM
Last edited by I.D.C.E.; 07-22-2015 at 07:09 AM.
#176
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From: KY
Sure wish I had that much room in my engine bay. Your 26 is a good looking ride and the vid is nice.
Mine likes to cruse between 34 to 36mph (3500 to 3800 rpm). Did notice that as I got below 1/2 tank my prop slip is reducing slightly. The all anchor chain in my bow reduces the amount I can trim up and the plus on that is if I turn hard over everyone needs to hang on. The boat turns so quick that what isn't tied down goes sliding real quick. Found that out when a jet ski came around flying in across my bow. My thought is the B3 or B2 will turn about the same if it is trimmed in more at the turn. Would be nice to try and prove the theory
Mine likes to cruse between 34 to 36mph (3500 to 3800 rpm). Did notice that as I got below 1/2 tank my prop slip is reducing slightly. The all anchor chain in my bow reduces the amount I can trim up and the plus on that is if I turn hard over everyone needs to hang on. The boat turns so quick that what isn't tied down goes sliding real quick. Found that out when a jet ski came around flying in across my bow. My thought is the B3 or B2 will turn about the same if it is trimmed in more at the turn. Would be nice to try and prove the theory
#178
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From: KY
Agree from what I've heard is the B3 is good up to 50mph, then starts loosing out to the B1. Haven't heard anything in comparisons to the B2, then again they seem to only put them on heavy boats
#179
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AD, how do you like the turn-downs on your boat? I was thinking about a set of those for mine. I like the rumble, but I also miss the ability to run it through the prop and carry on a conversation without yelling. Guess I'm getting old.
#180
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From: KY
I do like the turndowns, and while mine are only about 4 inches under water at idle, they do a nice job of making everything quite enough to carry on a normal conversation. When running it is much louder but I think it helps also with the sound being reflected down. I can still talk to the wife as we cruise but do have to raise the voices.
Old guy here also
Old guy here also




