Mercruiser 888(Ford 302) engine swap for a 454.

Hello everyone,

So here is my little project, I currently have a mercruiser 888 but I recently found a mercruiser 454 motor assembly. My boat is a 1973 and the 454 is out of a 1992 Baja. I have yet to actually look at the motor but I am sure I will probably have to change the motor mounts but my big question is will I have to change my transom and/or outdrive? I know this may be far fetched but any information will be helpfull. Thanks all

Re: Mercruiser 888(Ford 302) engine swap for a 454.

I think you will need to change transom plate due to "Y" pipe and power steering set up,an that #1 outdrive wont live long under the torque of that big motor.

Re: Mercruiser 888(Ford 302) engine swap for a 454.

Thank you for the information, it was just an idea I had. I would appreciate any other information you can provide about the 888 setup and especially about the outdrive. I am trying to figure out its capabilities, and the easiest way to get more out of it.

Separate question:
The trim does not work as advertised. I have two up buttons and one down button. I assume that you use both up buttons when you are trailering but I am unable to only use one button. I have to press both up buttons for the prop to move. Where are my trim indicators located? I have two rotted wires that go through the transom and I am wondering if these have anything to do with my issue or what those wires could be. Thanks

Re: Mercruiser 888(Ford 302) engine swap for a 454.

the two wires going through the transome are for your trim sensors..

Re: Mercruiser 888(Ford 302) engine swap for a 454.

but my big question is will I have to change my transom and/or outdrive?

Click to expand...

Ayuh,... Nothing from your current driveline is usable with a BBC,.... None...

Re: Mercruiser 888(Ford 302) engine swap for a 454.

the '73 drive is only good for about 300hp in prime condition. If you have the drive from the 454 take it, and the transom hardware and trim stuff.. take it ALL.

The Gimbal Housing is different from the '73 years to the '92 Alpha One. You may also have different gearing in the newer one.

as for the trim buttons, if wired properly and the Trim Limit Switch (located at the top of the gimbal housing) is intact, then you would need 2 buttons to "Trailer Up" else you should/could only use 1 which is fine, doesn't do anything different except when underway you wouldn't want to run trimmed up higher than where the TRIM UP LIMIT Switch is Set.

As for the trim indicator, you should have a hose coming to and from a peice mounted on the inside of the transom that also has 2 wires this gets wired into the Trim Gauge.

If you go with the new Gimbal Housing setup the old trim gauge sender goes un-used. But you can still use the old Trim Buttons.