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Discussion Starter · #1 ·
Anyone have "real world" numbers of changing from a standard length drive to a shorty?
This info is needed for a drive change ONLY.
Not adding boxes -engine mods-etc.

Just drive height change....what did it change in props and handling?
 

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Horsepower Junkie
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I'll let you know. Whenever I find a set of shorty's I'm going to swap them out and see what happens. If I can't find a set soon, I'm just going to buy some imco cases and put my guts in them.

I'll report back,
Frank
 

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GOOD , hurry up Frank. Inquiring minds want to know :)
 

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Horsepower Junkie
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Cal, you ever measure how far your propshafts are from the bottom of the boat? I measured mine and they are 6" below.
 

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Horsepower Junkie
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Wow!! I was told that the latest Powerplays that came out of the factory were 2 to 4" below the bottom.

You know they do make a 3" shorty ;) :D

Frank
 

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Well it isn;t good on my boat.Imco 2 inch shorty eats up all my new power.Tried a 23hydro 14 3/4 dia, 24 bravo 1 and a huge 27p 4 blade hydro.Different rpms same top speed.Only a little more than last year with at least 150 more ponies. :dead1:
 

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I only gained about 2 MPH but handling improved dramaticaly.
I still have to trim quite high - I need 12 inch stand off boxes.
 

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cookin said:
Well it isn;t good on my boat.Imco 2 inch shorty eats up all my new power.Tried a 23hydro 14 3/4 dia, 24 bravo 1 and a huge 27p 4 blade hydro.Different rpms same top speed.Only a little more than last year with at least 150 more ponies. :dead1:
So you added HP and a shorty at the same time?
Very hard to make comparisons that way because you can't differentiate what did what :confused:
I always try to do one thing at a time so I know what to blame :laugher: :laugher:
 

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I've done this upgrade on my last 2 boats, (35 Fountain HP 500's) & my current boat 31 Cat , 3-6 mph gain, my fountain went from 81 to 84 & my cat went 102 to 107 try to research s to see if someone has tried it first on your specific hull, (not a cheap upgrade), I knew what to expect as I found someone on OSO who had the same hull with similar + results.
 

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Ran-Dom32 said:
try to research s to see if someone has tried it first on your specific hull, .
I think thats the point of this thread. ;)


272 Formula in particular :D
 

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Mopower said:
I think thats the point of this thread. ;)


272 Formula in particular :D
Being how low your drives are now, I would would say for sure you will benefit just from the reduction in gear case drag. Older boats had lower x dimensions because 4-5 & 6 blade props did not exist, prop technology has made leaps & bounds in the last 10 years, Fountain in particular has raised the x on their boats over the years, so much that some boats came out of the factory to high & some had to space back down to dial in to a reasonable slip number.
 

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Mopower said:
So you added HP and a shorty at the same time?
Very hard to make comparisons that way because you can't differentiate what did what :confused:
I always try to do one thing at a time so I know what to blame :laugher: :laugher:
[/QUOTE It wasn't supposed to be that way,installed the foot with the old power and ran out of weather before I could try it.Had my old engine sold so I had to pull it.Lesson learned.It is for sale -2 imco shorty 2500.I need a bravo 1 lower.Any help?No,I can't lend out the shorty.
 

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I was able to sell the shorty and get a stock foot.Install on Monday.I will be more careful who I listen too next time.
 
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