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MarcP
07-12-2008, 01:11 PM
Hi everyone,
I'm new to the forum and thank you for allowing me to be a part of it.

My question is -- If I purchased a donzi ragazza with an OMC cobra, if I removed all omc components, would my Mercruiser Alpha One line right up to the same hole? Also, what if it was an OMC King Cobra... would my Mercruiser line up to that? (Is there a difference in the transom hole for an omc cobra vs omc King cobra?

And while I'm on the topic of the Donzi Ragazza, is the 25' underpowered with just a 5.7 liter? I'm not looking to go over 35, but would want it to be able to get up on a plane and cruise..

Thank you in advance for any responses..

BigGrizzly
07-13-2008, 08:55 AM
Keep the drive and prop it. the Merc is weaker and will not be any faster.

MarcP
07-14-2008, 09:36 AM
I'm not sure if it has the actual drive itself. It's an OMC King Cobra transom assembly. Also, since OMC's aren't made any more, I figured that there would be more parts available for the Mercruiser.

Any answers as far at the conversions? OMC Cobra to Mercruiser & Omc King Cobra to Mercruiser?

mrfixxall
07-14-2008, 10:19 AM
like griz said keep the omc drive on the boat,,their stronger and parts are still available..

MarcP
07-14-2008, 01:38 PM
The entire engine package that I'd be dropping into this boat is Mercruiser. It would cost me a lot more money to buy an OMC drive and then convert the Mercruiser engine to OMC stuff (exhaust manifolds, risers, etc).

I really appreciate everyone's input, but does anyone know the answer to the actual question that I was asking?

MarcP
07-16-2008, 10:05 PM
Is the transom bolt patern and hole size for an OMC Cobra or King Cobra the same as a Mercruiser Alpha One?

mrfixxall
07-16-2008, 10:52 PM
Is the transom bolt patern and hole size for an OMC Cobra or King Cobra the same as a Mercruiser Alpha One?

No! close but no cigar,,you would have to glass the hole back up and reconfigure the x dimension

cutwater
07-17-2008, 08:27 AM
Hi Marc - Like mrfixxall said, I believe I have heard the cutout for the OMC Cobra drive is similar, but it is not an exact match. Now, if the transom assembly is all there, I would think you could use a Merc engine (they should all be pretty standard SBC blocks. Somebody correct me if I'm wrong). It would be some work, though, to use a Merc drive because not only would you have to change the transom assembly/bolt pattern, but you would probably have to change the drive height also which would require glass work.

There used to be a conversion kit from OMC Cobra to Volvo SX drives (which are a little easier to find). The SX is a good drive, very similar to the Cobra. Try looking online for the kit.

John

BigGrizzly
07-17-2008, 09:04 AM
The OMC King Cobra is the same as the BravoI

GoDaddy
07-17-2008, 09:20 AM
Hi all!, This is my first post, I have a '90 16' I use on the south shore of Long Island. Long story short I jammed a 383 stroker and a bravo 1 in the hole that the OMC cobra had been by drilling out the two top transom assembly bolt holes. I guess that a merc alpha would probably fit right in without too much hassle too. The cobra was a great drive and I got almost 68 mph. with a mild 383 in front of it. I did the merc conversion because the salt took its toll, and the previous owner was a hack!
I hope you all have a great summer!, see ya in the bay.

MarcP
07-17-2008, 10:45 AM
Thank you everyone.. GoDaddy -- was the wiring much different for the omc than the mercruiser?

BigGrizzly
07-17-2008, 11:50 AM
Wlcome godaddy, glad the boat found a good home.

joseph m. hahnl
07-17-2008, 04:40 PM
Is the transom bolt patern and hole size for an OMC Cobra or King Cobra the same as a Mercruiser Alpha One?

Aren't OMC Fords? Mercruisers Chevy?
wouldn't the coupler be different as well?

cutwater
07-17-2008, 04:48 PM
Aren't OMC Fords? Mercruisers Chevy?

Not always. My Minx was an OMC SBC 350. But you're right, OMC did make a lot of 460 BBFs.