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Old 09-11-2009, 07:21 PM
honcho2 honcho2 is offline
 
Join Date: Sep 2009
Rep: 10 Posts: 2
Location: BC,Canada
what legs will fit a 470

I was wondering how interchangeable the legs are. My 470 is around 1982 model, so generation 1 I think. Will any of the newer legs fit like an alpha 1? Also, will I have to stay with the same gear ratio or can I re prop it. I would prefer to find one the same and save any hassle, any suggestions would be appreciated. Randy
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Old 09-13-2009, 01:53 PM
Red Tide Red Tide is offline
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Join Date: Sep 2009
Rep: 68 Posts: 58
Location: MA
You should be able to put an alpha 1 Gen 1 Leg on without issue but you need one with a short input shaft. SEI offers these as replacement drives if you're on a budget. A couple people have mentioned a minor problem with trim ram line interference with the new drive plate, but this can be easily modified or the cylinders turned upside down to clear the interference.

Is your drive a 1.81:1 ratio now? How as it performing?

Unless you have a reason to want to change the gear ratio (other than a slight change new gears vs. old gears but still basically the same ratio that you won't notice the difference) I would stick with the ratio that was working and the prop you have.
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Old 09-13-2009, 06:11 PM
honcho2 honcho2 is offline
 
Join Date: Sep 2009
Rep: 10 Posts: 2
Location: BC,Canada
Thanks Red Tide. I think it's 1.84:1, and with a 21 pitch it turns about 4200rpm wide open, pretty close to what it should run at I think. I normally run at 3000 to 3600 rpm when cruising, about 28-35mph.

I found a leg from a 160, I think it's a chev engine and it around 1.65:1, I'm thinking that's a big change. You're right, I'm on a budget, I'll check out SEI. I still have the gears from my broken leg in good condition, so I might be able to swap them. Thanks, I'm still looking and weighing my options
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