Can a -3 Imco be installed on a bravo1? Does it require modification to bolt up? If so, what needs to be done?

Yes it can but you need to modify the rear of the upper or you will be limited on prop diameter

The cavitation plate will need to be notched/stepped so the prop has clearance

It will clear a stock Bravo 4 blade prop. All You have to do is install the cavitation plate that comes with the lower and cut off what hangs below it. About 1/2 inch. I used a sawzall with a 12 inch metal cutting blade using the bottom of the cav plate as a guide. That is what I did to mine. I am running it on my Daytona.

Do you have pics to better help me see it?

This is a complete imco -3" drive as you see there is a step in the cavatation plate .
its for sale by the way

I wish. Why are you selling

I have a 21 v hull whit 560 hp ls that I m converting to normal 5.0 mpi bravo to make it affordable to sell as I m building a new cat for speed whit twins ,going to use the ls for that and have 2 new xr s for the cat

used the imco for 15 hrs I bought it from the owner of revolution marine that used it on his personal boat for 30 hrs then he switched to scx-4

Picture ?

If you only plan on using a Bravo prop than you can just bolt on the cavitation plate that comes with the lower and cut off what hangs down below it. This is how mine looks.

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