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Conquistador_del_mar
07-25-2008, 12:43 PM
I just bought an entire Bravo III drive setup from a friend in the boat repair business for a future project. I was toying with finding a 27' Magnum Sport or Cigarette 28' SS to restore using a single engine with the Bravo III drive. Does anyone know what HP can safely be used with the Bravo III and how dependable the drives are? I am not trying to set any speed records, but I would like a decent performing dependable single engine classic deep V for our relatively large Lake Texoma here in north Texas. Any input into the Bravo III drives would be appreciated. Bill

Morgan's Cloud
07-25-2008, 01:42 PM
Bill , the amount and variety , not to mention quality, of the restos you have done is always impressive. Is this one 'new ground' for you though. ?
I always thought the BIII had the same factory rating as the B I but you might be talking more about HUGE numbers and reliability than just 'stock factory ratings' .
As strange as it may sound I have a BIII in my 'other boat' a Mag 25 .
A 502 Mag in it and it handles really nice . My mechanic , an ex powerboat racer , LOVES to take it for test runs even if there is nothing wrong !
As this was a ground up resto I had never run the boat previously with any other sort of power but I'd say that the stern lifting qualities of the BIII are noticeable.
And it's not really that much of a slug what with those drag producing twin props .. On a good day it will do 60 and you know those Mags aren't exactly light for their size .
Steve

MOP
07-25-2008, 01:46 PM
Can't answer the HP question but I would bet similar to a B1, you cannot beat the handling and stern lift on azz heavy boats.

Conquistador_del_mar
07-25-2008, 03:26 PM
Bill , the amount and variety , not to mention quality, of the restos you have done is always impressive. Is this one 'new ground' for you though. ?
I always thought the BIII had the same factory rating as the B I but you might be talking more about HUGE numbers and reliability than just 'stock factory ratings' .
As strange as it may sound I have a BIII in my 'other boat' a Mag 25 .
A 502 Mag in it and it handles really nice . My mechanic , an ex powerboat racer , LOVES to take it for test runs even if there is nothing wrong !
As this was a ground up resto I had never run the boat previously with any other sort of power but I'd say that the stern lifting qualities of the BIII are noticeable.
And it's not really that much of a slug what with those drag producing twin props .. On a good day it will do 60 and you know those Mags aren't exactly light for their size .
Steve

Steve,
Yes, it would be a little different for me - restoring a Magnum or Cigarette and going from twin to a single drive setup, but I don't think it would be that big a problem. I almost bought a Magnum 27 on ebay a couple months ago, but I sort of chicked out after thinking about powering it along with needing everything. The reality is that I start from using very few of the original parts anyway, so doing it all would not be that different. Thanks for the input on the Bravo III - it sounds like a very good dependable choice. I was thinking in the 500HP range which I believe would push one near 60MPH - they are indeed heavy boats! Bill

The Hedgehog
07-25-2008, 03:45 PM
That would be a very cool project. I came very close to owning a 28SS one time.

Conquistador_del_mar
07-26-2008, 12:17 AM
That would be a very cool project. I came very close to owning a 28SS one time.

I bought a 1977 28SS once in about 1992, but I sold it before doing anything with it. The transom had been filled for outboards as I was told. It was originally red, but here it is after the buyer finished the restoration. It would have been a great candidate for going single. Bill

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=018&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=280242476131&rd=1

Morgan's Cloud
07-30-2008, 08:33 AM
Unfortunately , when you get into the single (larger) installation on an older Deep V , especially when you're planning to run more than stock HP through the unit , durability always becomes an issue . Part of the territory I guess with these heavier 'vintage' boats that they always seemed to have twins in them once they got to 27 feet or so but what with the huge gains in power output in 'stock' big blocks in the last 30 years many are begging for a nice singe engine conversion.
I recall seeing somewhere not too long ago that Merc was producing a 'higher performance' line of BIII props , so that might say something about the viability of the unit in terms of adaptability to better performance ...
Steve

Conquistador_del_mar
07-30-2008, 10:51 AM
Unfortunately , when you get into the single (larger) installation on an older Deep V , especially when you're planning to run more than stock HP through the unit , durability always becomes an issue . Part of the territory I guess with these heavier 'vintage' boats that they always seemed to have twins in them once they got to 27 feet or so but what with the huge gains in power output in 'stock' big blocks in the last 30 years many are begging for a nice singe engine conversion.
I recall seeing somewhere not too long ago that Merc was producing a 'higher performance' line of BIII props , so that might say something about the viability of the unit in terms of adaptability to better performance ...
Steve

Steve,
Thanks for the thumbs up on the concept. I know around here, I have been hearing that the twin engine boat sales have really died off due to gas prices. I am hoping that as long as I don't install too much engine that the Bravo III should be a great candidate for modest performance and good handling. I didn't know about the lifting aspect of the drive as you and Mop mentioned. After doing a little research, I did discover that quite a few BIII owners have had a problem with corrosion, but I always trailer my boats so that will not be a concern. I also learned more about corrosion/galvanic prevention in that different anodes and electrical systems are being used to help prevent it. Aluminum, magnesium, and zinc anodes are used for various water conditions. Since I boat in fresh water, we have always used zinc anodes. Our Lake Texoma is decently high in salt since the Red River picks up salt from some salt domes on its way here. The salt content is actually high enough that the striped bass (an ocean fish) are able to self propogate here instead of having to be introduced every year like most lakes. Where I was heading is that we might be better off with one of the other anodes here. I digress, but I look forward to eventually finding a project boat for the BIII after restoring my old 1971 18'. Bill

smokediver
07-30-2008, 03:06 PM
the bravoiii boats are probably more likely to be left in the water over an alpha or bravo boat hence the amount of complaints .. stern drives do not do well left in the water fo extended periods of time ....

Fast Shafts
08-11-2008, 10:11 AM
I've got a 27' Magnum Sport hull I've decided to sell. This is a hull only, originally set up for twin TRS drives, also have bolsters and bench seat. If interested, $3,000. No trailer or hardware (rigging)
I'm only selling because I've got a raceboat and just found another hull I' want.

Donziweasel
08-11-2008, 10:28 AM
Bravo III is rated by Mercruiser to 525 hp. Mercruiser typically underates thier drives, so, 600+ is not out of the question. Only stock drive rated higher by Merc is the Bravo I XR at 600hp.

Conquistador_del_mar
08-11-2008, 10:40 AM
I've got a 27' Magnum Sport hull I've decided to sell. This is a hull only, originally set up for twin TRS drives, also have bolsters and bench seat. If interested, $3,000. No trailer or hardware (rigging)
I'm only selling because I've got a raceboat and just found another hull I' want.

Can you send me some pictures? Also, where are you located? I am definitely interested. You can PM me or send directly to my email - Dgill25960@aol.com Thanks, Bill

Fast Shafts
08-11-2008, 12:15 PM
Con,
I'm in NJ. I will try to get you pics in a few days-I'm computer illiterate, and will have to await the assistance of my neice. Overall the hull is in good shape.
I've got a class 6 raceboat, and I recently found a hull I can use to step up to class 5. The hull I'm looking at has a steel Myco trailer-I want an aluminum I beam. Perhaps we could work something out?? I would'nt be opposed to doing a road trip (1/2 way)??
I know a couple of well respected local members on this site who could probably take a look at it and post their findings.

Conquistador_del_mar
08-11-2008, 01:23 PM
Con,
I'm in NJ. I will try to get you pics in a few days-I'm computer illiterate, and will have to await the assistance of my neice. Overall the hull is in good shape.
I've got a class 6 raceboat, and I recently found a hull I can use to step up to class 5. The hull I'm looking at has a steel Myco trailer-I want an aluminum I beam. Perhaps we could work something out?? I would'nt be opposed to doing a road trip (1/2 way)??
I know a couple of well respected local members on this site who could probably take a look at it and post their findings.

I will look forward to receiving the pictures. If the Myco trailer would work for the Magnum, I wouldn't have a problem with buying it to get it here. Meeting me 1/2 way would also be great - we can talk about that later. Maybe this is meant to be - I just bought a 450+HP 383 stroker motor over the weekend that would work great as a package with the Bravo III. Bill

lildogcustoms
08-11-2008, 02:07 PM
Bravo III rated only up to 65mph according to Mercury website- I would assume that's a conservative rating but know speed and the dual prop setup has it's limits.

Forrest
08-11-2008, 02:40 PM
. . . I just bought a 450+HP 383 stroker motor over the weekend that would work great as a package with the Bravo III. Bill

But I not sure about a single small-block no matter how many ponies it's got pushing a Magnum 27. The Magnum is no lightweight. On the other hand, I'm all for the duo-prop idea, though.

Conquistador_del_mar
08-11-2008, 07:21 PM
Bravo III rated only up to 65mph according to Mercury website- I would assume that's a conservative rating but know speed and the dual prop setup has it's limits.

I would be looking to make a nice classic deep V cruiser for our relatively rough lake. If I got 60MPH, I would be pleased. Bill


But I not sure about a single small-block no matter how many ponies it's got pushing a Magnum 27. The Magnum is no lightweight. On the other hand, I'm all for the duo-prop idea, though.

I would like to see another one that someone has already powered the way I am thinking before doing it, but it wouldn't be the first time I have jumped off a cliff. I think the weight savings of a single drive would help immensely. A SBC with aluminum heads and aluminum exhaust making around 475HP would probably power a 27' Magnum to the mid 50s which is all I really would need for my planned usage. If worse came to worse and I wasn't pleased with the performance, I could go with a near 600HP BBC later. Bill

Conquistador_del_mar
08-12-2008, 12:24 AM
But I not sure about a single small-block no matter how many ponies it's got pushing a Magnum 27. The Magnum is no lightweight. On the other hand, I'm all for the duo-prop idea, though.

Here is the engine that I just bought. It is local and seemed like a good deal so I jumped on it. Bill
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&ih=018&sspagename=STRK%3AMEWN%3AIT&viewitem=&item=280251681971&rd=1

Morgan's Cloud
08-12-2008, 06:49 AM
Bravo III rated only up to 65mph according to Mercury website- I would assume that's a conservative rating but know speed and the dual prop setup has it's limits.
Even though this is hardly new information I wonder if it's ever really been proven .
The Bravo unit , as we all know , is running boats way over 100 !
Hydrodynamically the only visible difference in the B3 unit is the extended anti ventilation plate. So does that mean the rumored speed loss is due to the two props ?
How is it that the Volvo DPS , for instance , can easily run over 90+ MPH ?
Have Merc just not invested time in prop development for the B3 ?
Something else that comes to mind .... Just how fast are those Lipship Cig 20's with B3's ... I reckon that for their price , they go a good bit more than 65 !
Just wondering .....
Steve

olredalert
08-12-2008, 09:10 AM
--------Bill,,,Thats one heck of a price on that 383. Will they sell more for that price??? I dont see how they came out on top on that deal. Congrats on a really good buy!!!........Bill S

Conquistador_del_mar
08-12-2008, 10:32 AM
--------Bill,,,Thats one heck of a price on that 383. Will they sell more for that price??? I dont see how they came out on top on that deal. Congrats on a really good buy!!!........Bill S

Bill,
I talked to the seller yesterday. Scott told me that he has been building high performance engines for years, but the recent gas prices have been hurting his sales. He will be bringing the engine to me this next Sunday on a steel cradle ($40) that he jigs up. I told him how I was probably going to use the engine and we both thought the cam would work fine with the real torque coming in at 3500-4000RPM. I will find out more this next Sunday and ask him if he would sell any more at that price. If you want, you could call him at his number to ask any questions directly. He sounds like a good guy on the phone. 972-815-8054 Let me know what he says if you call him. Bill

Fast Shafts
08-12-2008, 11:55 AM
Con,
I was actually considering the same thing for the Magnum, a bravo III.
My father has a 28 Bayliner with a 454, 325 Horse, Bravo III and it runs over 40 MPH! This boat is over 7,500 lbs. I think it is very realistic to gain another 15 MPH with 2500/3000 less pounds. The only thing I was going to do different was to use a big block (already have one) Keep brainstorming! I'm still working on the pics-probably Friday.

Conquistador_del_mar
08-12-2008, 12:22 PM
Con,
I was actually considering the same thing for the Magnum, a bravo III.
My father has a 28 Bayliner with a 454, 325 Horse, Bravo III and it runs over 40 MPH! This boat is over 7,500 lbs. I think it is very realistic to gain another 15 MPH with 2500/3000 less pounds. The only thing I was going to do different was to use a big block (already have one) Keep brainstorming! I'm still working on the pics-probably Friday.

Very good. I will look forward to seeing it and the trailer. Yes, a BBC would probably be a safer bet, but I couldn't resist buying the 383 at the price. I once put together a 24' Excalibur with a 450HP BBC running a TRS drive that ran right at 70MPH and it was a 3600lb boat - also 24 degree deadrise hull so I don't think I would be far off the guess of near 60MPH with 475HP and the BravoIII in a 27' Magnum. I would guess the package I am putting together weighs roughly 400lbs less than the BBC/TRS combination as well - maybe more? Bill

MOP
08-12-2008, 12:54 PM
Some of the bigger model Donzi's came with BIII's and 500's, my buddy George has been running one for about 4 years now. He comes across LI Sound just about every weekend and does quite a bit of local running.

Conquistador_del_mar
08-12-2008, 08:14 PM
Some of the bigger model Donzi's came with BIII's and 500's, my buddy George has been running one for about 4 years now. He comes across LI Sound just about every weekend and does quite a bit of local running.

That gives more creedance to my gameplan. Thanks, Bill