Dave M

I had a boat with a Cobra for six years. As far as the reliability and durability of the drive, I never had a problems with it. The problem I was plagued with was the shift mechanism. I would get it adjusted just right, it would work great for a while and then hose up again. This was a known issue with OMC Cobra. If the two motors you have are the same HP, I don't think you will notice any performance difference.

Dave M.

fund razor

Dave M had a good point.

Liberator 21 on OSO knows Cobras.

I am learning. I've got twin 87 Cobras with SBCs. Everybody told me to dumpt those drives. But I spent a season trying to beat them, jumping out of the water like a ski boat, and I can't break em with the smallblocks. From an engineering standpoint, they are kind of a bigger boned version of an alpha. The hold three times the gear oil that an alpha does, so they run cooler. The impeller pumps are accessable without removing the drive.... big advantage over alpha if you run in shallow water like me.

The problem is resale. They don't suck as bad as the rumors say. It's a marketing/image problem leftover from the OMC/Merc wars. Actually it was the FICHT outboard that was the kiss of death for OMC.... but that's another thread.

If you decide that you want to switch. Screw the alpha.... a new 2004 Volvo sx drive is great with a smallblock and is the smoothest shifting drive in the business. period. You could rule at docking.
Best of all.... it WILL BOLT RIGHT UP TO YOUR COBRA TRANSOM ASSY.
The alpha transom assy will not fit your OMC cut out.

I have been researching this since May.

Enjoy your cobra... in the meantime look into the Volvo.

fund razor

By the way.... nothing wrong with mercs. I had an alpha for years. Got real good at rebuilding the pumps every year.

I would have preferred alphas for resale for sure.

mopower

That's because OMC didn't "go under" as such. Volvo bought them out when they were in financial distress. Volvo then took the better OMC design and dumped out the guts and added their own gears and cone clutch like a Bravo and came up with a rather good unit. Externally it looks just like the OMC but shifts as good or better than any Merc out there.
On another note , I did run a 625hp 540 thru a King Cobra for 3 years with no mechanical problems , but like Dave said , the shift can be a problem. They have an ignition interupter like Alphas to come out of gear. Their final shift module design was pretty good. I had no problem after that. I sold it in 2000 and still see it around and talk to the present owner who has had no problem.
I did take the 540 out and put back the original 460 Ford because it was a hand full to handle simce it was a 21' boat

fund razor

I have had issues with my shift interrupters (Had to replace one, 90 bucks) but they are easy to get to. I have also replaced both shift cables with the "warranty" update.

If your 1987 OMC shift cable jacket is black, not reddish orange, you have the "recall" cable, not the replacement. The kit is a hundred and a half I believe. The drive has to come off to adjust it properly. They had a real problem with dealers charging for the work, but not having done it.
That happened to me. A dealer in TN billed it out already, but it wasn't done.

Now it is. Both sides shift much better.