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ISO Blackhawk Gearcase and/or Complete Drive

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Old 01-08-2022 | 01:47 PM
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Default ISO Blackhawk Gearcase and/or Complete Drive

Interested in purchasing a Blackhawk gearcase, Blackhawk unique parts or entire drive. Unserviceable, repairable prefered, but will consider all.

Respond via PM and tell me whatyou have. Thank you!



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Old 01-08-2022 | 02:19 PM
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listed by "offshoredrillin" in Maryland

Custom Built Blackhawk, ITS box, 2 sets props 31p
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Old 01-08-2022 | 02:37 PM
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Saw that one. Thanks. The 1.36 gear ratio will not work in my application. Nice setup, however.
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Old 01-08-2022 | 04:56 PM
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Originally Posted by rotorr22
Saw that one. Thanks. The 1.36 gear ratio will not work in my application. Nice setup, however.
easy to switch it to a diff gear ratio, ITS box is sold with shaft, so only thing left is drive and a set of 31 props, 6k for drive, 1200 for prop, 7k for both.... the xz gear upgrade is good for higher hp

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Old 01-08-2022 | 05:41 PM
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I have 8 brand new gearcases and enough parts to build 2 drives.
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Old 01-08-2022 | 08:50 PM
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Thanks offshoredrillin. I'm a retired Mercury application engineer ( old fart), so gear changes are not the issue. I'm running a modest LS3 SBC and require a numerically higher GR based on the engine's HP and torque curve, otherwise I would have been interested in yours. It looked awesome!
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Old 01-09-2022 | 06:38 AM
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Originally Posted by rotorr22
Thanks offshoredrillin. I'm a retired Mercury application engineer ( old fart), so gear changes are not the issue. I'm running a modest LS3 SBC and require a numerically higher GR based on the engine's HP and torque curve, otherwise I would have been interested in yours. It looked awesome!
sure thing, interesting, what ratio are you trying to get to? above 1.5 i think the highest is 1.65 ?... i did mine at 1.36 behind 725 hp as i didnt want idle speed of 10 mph .
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Old 01-09-2022 | 12:09 PM
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A 1.65 would work for me, though one of our engineers did a 1.81 combo behind a stock 502 mag mpi motor with success.

Point taken regarding the idle speed. I 've driven my fair share of B3 powered boats and experienced similar on the lighter hulls. Can only imagine that it get's worse when the gearcase drag is reduced.
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Old 01-26-2022 | 07:46 PM
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I dont mean to steal the thread but its hard to find anyone with data on these drives anymore. What kind of slip numbers have you all seen on a BlackHawk drive when you at 40+mph?
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Old 01-26-2022 | 10:18 PM
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Originally Posted by River Rat 164
I dont mean to steal the thread but its hard to find anyone with data on these drives anymore. What kind of slip numbers have you all seen on a BlackHawk drive when you at 40+mph?
I don't think I've ever driven 40 MPH.

Two Mercruiser engineers I know who worked with them extensively back in the 90's were Steve Schoderer and Steve Donahue. Both are retired, but you might give FB a shot..
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