How much HP can a 1990 King Cobra take?

[Tahoe540]

First I would like to say this site has a lot of great info on the OMC drives as info is not easy to find. I am a new boat owner and long story short I bought a project boat for what I think is a pretty good deal and was told up front about the issues with parts and service for these drives but this drive is in perfect working condition. What I am trying to find out is how much HP can these drives take without causing issues as well as any do and don'ts or tips and tricks. The boat is a 1990 30ft advantage with a single motor and I am sure it came with a motor with decent HP. I am currently rebuilding the motor (540 BBC) to be about 600 NA HP. My plan is to hopefully use the boat over the next few seasons then upgrade to a new outdrive that can take some real HP. So will I be OK with this motor build? This is the cone clutch model. I would also like to hear what people suggest for an upgrade. I have looked at some of the options from Imco but wow they are big money. I would like to upgrade to something that can take over 800HP as I will be putting a blower on the engine at some point as this will be a Tahoe boat and need some high altitude help.

 

[vasy]

You want some serious HP... so be ready to spend some serious cash for it
Sime pictures would be nice

 

[Scott Danforth]

I doubt the OMG drive will survive. Then that is the whole thing about king cobra parts being NLA. I would swap to a mercruiser Bravo

 

[Tahoe540]

Thanks for the responses, my plan is to upgrade at some time so I guess I will put it back together and hope it will last a few seasons. Everything was supposed to be in running order when it was taken apart. Here is a pic of the boat.

 

[vasy]

Did some search and Seems boats with king cobra had up to 370hp in that time period.
So I'd not be mashing that throttle all the way forward from a dead stop, and watch the prop size, might need to go up a bit in size with 500+ HP

 

[HT32BSX115]

Thanks for the responses, my plan is to upgrade at some time so I guess I will put it back together and hope it will last a few seasons. Everything was supposed to be in running order when it was taken apart. Here is a pic of the boat.

Howdy,

Welcome aboard!

VERY NICE looking boat!

If you're planning to keep it and you do want to swap to a drive that is more supportable, your best bet would be to "baby" it until you're ready to start looking for a replacement.

When I removed my previous 460 King Kobra out of my 87 Four Winns Liberator and replaced it with the 97 454/Bravo III, I was able to sell ALL the OMG "stuff" over a few years for more than $3600! (I got $1450 for the drive alone!!) It took me a while but I finally sold the 2 props I had last month too!

My point is that you have a rather desirable drive because it IS so rare, and because many parts are NLA, there are people that want your parts.

For example, There's a guy here on iBoats right NOW, that needs a 90's 454/King Cobra Transom mount in his twin 454/King Cobra Cruiser because of severe corrosion.

Back when I sold all my 460 "stuff" a guy in Ca had a big Bayliner cruiser with a 460 KC that had the coupler fail and destroy the flywheel housing, inner transom plate and other "stuff"............ his insurance company was going to "total" the boat if he didn't find parts (that I had) to fix it.

So you have some pretty good stuff to sell (as long as they're undamaged)

I wouldn't put BIG HP on that drive if I was going to pull it and replace with Merc or Volvo later.


Regards,


Rick

Let me also add that I would pull it now and start looking for a Bravo I (x) drive/gimbal mount, and inner "stuff".

That boat will FLY with a BBC doing 500+ HP!!

 

[Tahoe540]

Thanks everyone for the replies, I have been doing more reading and am going to continue on with my project and rebuild it naturally aspirated and shooting for a good dependable motor. I have since had some time to pull the outdrive and clean it up and inspect it. From pics I have seen online and after I cleaned mine up I am feeling pretty good. It and the transom seems to be in pretty good shape. I ended up cutting an old wheelie bar I had from my dragster and made a stand and did a little clean up work on the outside. Ordered some paint so hopefully it will look good when done.