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Any Gains from a IMCO Shorty on a stock 502 MPI 25 Outlaw

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Any Gains from a IMCO Shorty on a stock 502 MPI 25 Outlaw

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Old 10-22-2017 | 03:43 PM
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Default Any Gains from a IMCO Shorty on a stock 502 MPI 25 Outlaw

Will I see any gains or advantages from installing an IMCO shorty on my 99 25 Outlaw? I know I will have to switch to a 4 blade as well
My boat is a basically stock 99 Outlaw with a 502 MPI and bravo one drive, only performance mod is Lightning exhaust manifolds.
This past weekend when launching my boat, my lower unit creamed some rocks, broke the tip off of my skeg and chewed up my prop pretty good. I knew the Lake (LOTO) was low so only had my drive down 1/4 of the way down when it happened. My depth finder said that I was in about 4-4.5ft of water when I was launching and when I was about 10ft out from the back of my trailer, while in reverse, it sounded like I struck a concrete barrier. Other than the physical damage, there doesnt yet seem to be any other damage to the lower unit. The boat shifts fine still, but I believe my cooling system sucked quiet a bit of **** in because for the first time ever, my boat started to over heat, so I am assuming my impeller felt the wrath as well.
Since I am going to have to incur the costs on the prop and skeg, I figured I would entertain the extra expense on a shorty if I would gain anything from the swap.
Thank You
Scott
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Old 10-22-2017 | 04:38 PM
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My 24 ran much better with the -2 shorty but I had 650hp and ran 80. They seem to eliminate any chine walk or instability in the deep x dimension baja's
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Old 10-22-2017 | 05:02 PM
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short answer is, yes and no. it would depend on how high it is now. if it is set pretty deep then you will probably see an improvement with the right prop. while you dont have a ton of power it is still decent and a somewhat small boat so if you are replacing the lower anyway I would go for it. worst case you can always space it down 1" but you will probably be happy with the change.
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Old 10-22-2017 | 06:23 PM
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Agree, if you install a -2 you can always run spacers if needed.
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Old 10-22-2017 | 07:25 PM
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how many inches is considered deep in terms of prop shaft location on a single V w/ bravo ?
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Old 10-22-2017 | 10:15 PM
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What size prop shaft would be best?
Also, is a 26p bravo 1 to much pitch, or should I go with a 24p? Im spinning a 24p mirage plus now
Since Im not making a ton of power, can I get away with #'s 1 or 2, from below, or do I need the "Complete" deal for $3,350 or $3,526?
1. Case only incl. vertical shaft & bearing ..........................$1,195
2. Case only using your existing vertical shaft....................$1,678
Note: transfer your Bravo lower gears to Imco Case .......$375
3. Complete 1:50, 1" Prop Shaft .....................................$3,350
4. Complete 1:25 or 1:34, 1" Prop Shaft...........................$3,526

Last edited by QualityTime; 10-22-2017 at 10:29 PM.
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Old 10-23-2017 | 08:43 AM
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what kind of rpm and speed were you getting with 24 mirage? 26 will drop WOT rpm's by close to 10%. your bravo isn't dead, just ugly. I would leave it intact and get complete lower. you could hate raised drive like poison. if so, the ability to go back to stock and re-sell the shorty is still there. beat up skegs have very little effect on performance. I ran an alpha with NO skeg for quite a while. and don't even think about 1.36 ratio without greatly increasing your power first.
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Old 10-23-2017 | 09:39 AM
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Originally Posted by QualityTime
What size prop shaft would be best?
Also, is a 26p bravo 1 to much pitch, or should I go with a 24p? Im spinning a 24p mirage plus now
Since Im not making a ton of power, can I get away with #'s 1 or 2, from below, or do I need the "Complete" deal for $3,350 or $3,526?
1. Case only incl. vertical shaft & bearing ..........................$1,195
2. Case only using your existing vertical shaft....................$1,678
Note: transfer your Bravo lower gears to Imco Case .......$375
3. Complete 1:50, 1" Prop Shaft .....................................$3,350
4. Complete 1:25 or 1:34, 1" Prop Shaft...........................$3,526
For 200 bucks, Id go with the 1.25
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Old 10-23-2017 | 04:23 PM
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I thought that was gear ratio, not shaft diameter...
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Old 10-23-2017 | 05:53 PM
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Never do a 1 inch shaft even stock HP.
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