17ft, 1989 Donzi Raggazza, could I swap to a larger OMC engine and sterndrive?

USAFcrewchief

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Feb 21, 2019
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I did a coast to coast search for a 3.0 cobra engine, nothing. I did run into a "V" six cobra and tons of Mer Cruisers. How hard is it to go higher into OMC Cobra's or even go to 3.0 Mer Cruisers engines.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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welcome aboard.

the 3.0 is a GM motor, no mater if its a mercruiser, volvo-penta or OMC

if you want a bigger motor, i suggest you sell your boat and buy what you want, preferably with a Mercruiser or Volvo-Penta in it, as OMC has been out of business for decades.
 

Lou C

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Nov 10, 2002
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Before doing anything to a 30 year old fiberglass/wood boat, check the structure for rot!
Also, as Scott said, OMC has been out of business about 20 years, yes you can still get most Cobra parts but it is very hard to find techs who can or will work on them. I do all my own maintenance, there are 2 shops around here who will work on them. If the boat is solid, you could just repower it with a GM marine 3.0. If you want to go bigger, the biggest I'd go is a 4.3 V6 which is shorter but wider than the 3.0. At the same time you'd have to fabricate new mounts for the V6 engine and while you're at it, I'd sell off all the OMC stuff on ebay and just buy a pulleys to prop package Merc or Volvo package. In the long run, best bet if you must keep the boat.
 

Bondo

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How hard is it to go higher into OMC Cobra's or even go to 3.0 Mer Cruisers engines.

Ayuh,..... Welcome Aboard,..... Is the motor beat,..?? How so,..??

As Scott said, OMC has been outa business for decades,......

To drop in a Mercruiser, ya remove Everything OMC, 'n drop in everything Merc,.....

Good news is,.... The hole in yer transom is the current industry standard,...... copied from Mercruiser,.....
 

HT32BSX115

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Dec 8, 2005
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How hard is it to go higher into OMC Cobra's or even go to 3.0 Mer Cruisers engines.

Howdy,

Welcome aboard!

Pretty easy! I swapped a 1987 460/OMC King Kobra for a 1997 Mercruiser 454/Bravo III in my 87 Four Winns. All it takes is MONEY!

You can minimize the cost by finding a damaged (hull) boat with the engine and drive you want

But it's not worth it if your boat is "rotten" anywhere in the engine room or floor (transom, stringers, etc)

If that's the case, part it out and find another boat of your dreams!

Cheers,

Rick
 
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