Alpha to Bravo swap?
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Has anyone done a Alpha to Bravo swap? What does it entail? New transom hole? Transom plate? Gimbal? etc. Are any parts interchangeable? How much power can an alpha drive reliably handle? Thanks in advance for any help.
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How much an alpha can handle depends on a number of things, boat, weight, use. . . The bravo swap is fairly simple. I know just enough to be dangerous here but you don't need a new transom hole just two additional bolt holes. There have been other threads on this, try a search. I'm sure someone will let you know the details.
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you'll need the complete Bravo, Bravo transom assy and a belt driven raw water pump set up......apparent ly the swap out is fairly simple.......like F38 says, do a search
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Outdrives.com used to offer a complete kit to change from an Alpha to Bravo. Not sure if they still do.
http://www.outdrives.com/
http://www.outdrives.com/
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Many years ago I converted an alpha transom assembly over to a Bravo. It can be done, but trust me when I say you're better off just buying a Bravo transom assembly. I ran the Bravo a year and didn't like it (18' Formula with a 406ci SBC) so when I converted back to an Alpha I just bought a used alpha transom assembly.
Trigger outlined the rest...
Trigger outlined the rest...
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Steve Gresham
'03 Donzi 33ZX
Steve Gresham
'03 Donzi 33ZX
#7
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The swap is fairly simple, like they said you just add two more holes in the transom and add a fresh water pump.
the only problem I can see is your X-Dimension. The bravo sits deeper in the water so if you do the swap your X will be lower. In addition to the X, you'll loose a little more speed becuase the Bravo sucks up a little more power.
Good luck on an Alpha if you have a big block, they only made a few Alpha Big Blocks and for good reason. To much torque for those drives.
the only problem I can see is your X-Dimension. The bravo sits deeper in the water so if you do the swap your X will be lower. In addition to the X, you'll loose a little more speed becuase the Bravo sucks up a little more power.
Good luck on an Alpha if you have a big block, they only made a few Alpha Big Blocks and for good reason. To much torque for those drives.
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Ok ! Listen up , if you are running under 400 Hp you can easily get away with an alpha 1 with a 1:32 GEAR RATIO OUTDRIVE.
I'm not bs'ing you this can and has been done. 1986 and 1987 454 alphas had 1:32-1 drives. I have been on several worked boats with alphas that had at least 450 Hp.
I'm not recommending this but it has been done and will work if the boat is not beaten on. I myself blew up several alpha lower units when i ran them 1.50 - 1 with a big block. It seems that when the lower is slowed down , esp. w/ the 1.32 upper the whole drive survives ! Try to use the newer 1990 and up style driveshaft without the groove for more durability. Bravo would be better, but really still is a toy compared to what is out there powerwise that will eat a Bravo as a snack. Unfortunatelly it comes down to $$$ (which I don't have enough of) BBB
I'm not bs'ing you this can and has been done. 1986 and 1987 454 alphas had 1:32-1 drives. I have been on several worked boats with alphas that had at least 450 Hp.
I'm not recommending this but it has been done and will work if the boat is not beaten on. I myself blew up several alpha lower units when i ran them 1.50 - 1 with a big block. It seems that when the lower is slowed down , esp. w/ the 1.32 upper the whole drive survives ! Try to use the newer 1990 and up style driveshaft without the groove for more durability. Bravo would be better, but really still is a toy compared to what is out there powerwise that will eat a Bravo as a snack. Unfortunatelly it comes down to $$$ (which I don't have enough of) BBB
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thanks again...
Panther and BBB, the boat has a 350 sbc which I guess is pumping about 260-275 hp. If I were to upgrade the drive it is only to drop in a bbc........
perhaps drop in the bbc and see how it goes with a 1:32 to 1?
the boat is a 24' Monza sport deck....like a Pantera........
Panther and BBB, the boat has a 350 sbc which I guess is pumping about 260-275 hp. If I were to upgrade the drive it is only to drop in a bbc........
perhaps drop in the bbc and see how it goes with a 1:32 to 1?
the boat is a 24' Monza sport deck....like a Pantera........
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The gears are $408 from Bam. I have not seen them aftermarket. Make sure that they are shimmed perfectly. I did one for someone this summer, It's a pain and it takes a while, taking it apart , preloading, moving shims, checking clearance, pulling bearing races, etc. It may have to come apart several times to get everything right. The Merc. book must be followed to a t. Also at least check the backlash on the lower. If not done right it will shear the pinion gear right off. This happened to me when I had some local shop put a drive together, before I had all the tools. Make sure everything in the drive is good. Bearings , seals, etc. Also should go with improved shift spool in lower unit unless it already has one. 1990 and up should be stainless instead of brass. BBB