What drive is this and what HP can it take??

[CodyGrizz]

Howdy, I have a 1989 Bayliner Capri with a 140hp 3.0l OMC engine. My outdrive says OMC Cobra on it and was told it was a Alpha1 outdrive..this true?
Also, what HP can i put to it and what engines can I use? I was told i couldnt put a bigger engine on it on another forum yet I have seen pics of this same boat with a 5.0 and same outdrive stock, what gives?
I love my little boat, its fun, but not fast enough and I wouldnt mind throwing a bigger engine on it but do I have options? Like using a truck engine?

[mach1alaska]

I am not that familiar with OMC drives but it is not an alpha 1 as that is made by Mercruiser

[CodyGrizz]

Thanks for the reply. I was told it was a "pre-alpha alpha" by a OMC dealer. As in it was an Alpha1 with the OMC badging on it like the engine was..made sense but wasnt sure if it was true or not. I know Mercruiser 140hp 3.0l stuff fits my Cobra engine so i thought maybe they ment it..now I am not sure and wonder what it can do. I know I could put a new mercruiser engine on it with no problem..the 3.0 at least, so have to ask!!

[Havasu47]

It is not an Alpha I as mach... said. The OMC Cobra can hold up to a small block v-8 no problem. You might have a problem with the gear ratio being too low. Usually you can make up the difference with a larger pitch propeller depending on the gear ratio.
A 4 cylinder usually has a very low ratio and you would probably have to change gears.

[CodyGrizz]

Much thanks. THAT is what I was hoping to hear! How do I know what gear ratio it has? I looked all over it and couldn't for the life of me find a serial number or anything to look up. And do I have to use a marine engine or will a truck small block work? I think this would REALLY wake my little scooter up and I would be MUCH happier. I love the look of the boat and am redoing the interior to get rid of the doghouse and side seats and will be running a bench with large sun deck and taking out the back/back seats and throw in bucket style so I would have the room for a bigger engine no problem.
Now what would I have to do to make a truck small block (I assume a 350 vs a 305) work with my outdrive? I assume some sort of bellhousing? The outdrive was rebuilt when I got the boat 2 years ago as it had blown a seal and the dealership I bought it from fixed it so I guess it would hold the power well. How much HP should I stick under? I looked around on the web and found out what I guess is what they call my outdrive..the OMC 400. The 800 was for V-6 and V-8. And the boards I was reading said that you cant put anything bigger than a 4cyl engine to them and expect them to last long. Just seems weird my engine is rated at 140hp and the outdrive couldnt handle..say..200-230hp. It seems to be a fairly light boat so It would scoot pretty good. Thanks again for the replys!!

[dicudmore]

you would be money ahead if you just sold that ride and bought something with more power...

[CodyGrizz]

Why when I have this boat and love it? I bought it cause I liked it..and if I can make it faster cool. I am building a boat..25'..this is just my cruiser and she wont be going anywhere anytime soon so the cost of an engine upgrade would be fine with me. Heck i would be happy with 200hp if the outdrive can take it, be much nicer than my 140. Shoot..50% increase in power..all good if its possible with my Cobra outdrive!

[LCexplorer]

I am almost certain that your OMC Cobra has a 400 housing which would be smaller gears (somewher around 2:1) and smaller shafts which were built for 4 cyl use only. There is even a physical difference in gearcase size between the 800 and 400 series lowers. Any type of power beyond a 4 cyl would probably mince meat that lower you currently have. The two gearcase size (400/800) from OMC was a hold over from their previous generation designs and stuck with it for some odd reason with the Cobra. Anyhow you will be better off selling the drive you have and getting the correct 800 series drive for the boat. As for dropping in 350 from a truck, you might want to start with an OMC motor with all the acccessories. But this stuff is considered old and outdated, so should come relatively cheap.

[waterlogged3261]

i have one that had a 302 in front of it for sale.
chuck

[CodyGrizz]

Well I guess I COULD sell my whole setup to help offset the cost of the bigger engine/outdrive. I just want around 200-210hp with my boats lines..it would be great! I just cant justify in ANY way the 3-5k I see the setups going for, thats just not worth it to me. If I can doo mine and like $500, thats worth it. But then again..maybe I am off my rocker..

[DMOORE]

If you would be happy with 200hp or so, you may want to consider a small supercharger. You could possibly bolt up a small Vortech or other centrifical blower and set it up as a blow through design. They come up on ebay all the time. It could give you another 50-60hp fairly easy, and with a little fabrication on your part, could save you time and money. Also it would add very little extra weight to the boat ( very important with a small run-about) to keep the handling as-is. If you keep the boost down to 4 or 5 psi, it would still run great on 91 octane. Just a thought.
Darrell.

[CodyGrizz]

A supercharger on a 3.0l OMC Cobra?? Now THAT would be a sight!! Isnt this engine based on a GM engine..or something like that? I mean if I could add 50hp and keep my engine, that would be fun! Then if anything ever happened maybe throw a Buick V6 or something in. But will my OMC400 outdrive TAKE 200-210hp?

[DMOORE]

The 3.0 4 cylinder is a marine only motor. It is just like anything else, it you take care of it and do not abuse it , the drive will last for years. On the other hand, if you beat the shit out of it, it isn't going to. Some people can break a bowling ball. And no matter how strong a part is, they will break it. To me it would not make sense to change out the motor and drive in a small run about. Too much cost plus added weight of the larger package.
Darrell.
EDIT: BTW it is a GM product.

[CodyGrizz]

I hear ya, but power is always nice to have. I know my exact boat came with a V8 in it, and it scooted, thats why I ask. I love my boat. The lines on it..they are great. It has the Euro windows..2 side pieces that sweep back most of the boat, it just caught my eye and i bought it. i know it wasnt as fast as I was use to or wanted, and tried faster, but came back to it and had to have it. So if I can put more power to it..it would be great. My speedo claims 40-42, not sure how accurate it is.Its a light boat, drives great, and worth to me whatever I put in it. I really doubt i would sell it anytime soon, thats why I am building a bigger boat, but want a little more "oomph" if ya know what I mean.
Reason I asked if it was a GM engine as if it was based on a car block design it might be easier to get a turbo or supercharger setup going. 50% more power would put me in the 200hp range..fine by me!! I am use to Turbos on the cars we do but they are kits you just install and tweek, this would have to be hand made I am thinking. but boy what a project!!
Anyone have a link to a good site about this? I am looking but not finding. I mean I have a flex connector at the back of my header that I could connect a turbo to..then have a tube made bending it to a box that mounts to my stock manifold and that the carb sits on top of. Might work..maybe.
Would I replace the 2 barrel carb with a 4 barrel while I am at it so I am getting in more fuel? I am thinking it would actually be a fairly simple project in my boat since it has that single connector on my engines header. Then run the exhaust through hull or through the stock connector? Through hull would sound cool as turbo exhaust isnt as loud as regular headers and would make it that much different. And with a small turbo like I would need..less lag? Thoughts? Suggestions?

[pocketchange 22]

[
To answer your question, the older blocks were based on the 4 bolt main corvette block. that means there are 4 bolts on your crank bearings, for more streanth, and longer rpms. Some of the newer blocks are only 2 bolt mains.
Fore the average person that is pleanty strong. If your going to run big power 400 hp+ 4 bolt is a must. In some theroy boat motors and circle track are built almost the same. As far as the turbo question, various things to know.
1. They make lots of heat! If you don't have vents ur compartment is going to be an oven.
2. Expenseve, and you can't just install a turbo, and hope it runs by connecting the exhaust side to it, remember, H20 exits from your manifolds.
Water and hot exhaust DON'T mix!
3. By the time you r done spending your summer with your hatch up and down your gonna want to drive the boat into a bridge abutment.
4. On the uphill side, it is free horsepower, and if you finde a kit from a place like vortec, you'll mite have some thing.
Personaly it's a lot of money, by the time your done you could have a new block, built very strong, reliable, and be at the same price maybe less.
there are many machine shops around, if you notice all the big power boats never have turbos, not to say Blowers don't make heat. Exhaust charge dosen't power the intake, the pullies do.
One can go on for a while about turbo principles, ( granted it's only my 2 cents) Not really the way to go for more ooomph
I am currently building a 383 sbc stroker,
AFR 195's aluminum heads, 750 holley carb, Edelbrock intake, etc. All brand new parts, balanced, blueprinted 450hp, 480torqe +/_ I'm into it for under 6k, not including the dyno charge.:devil:
Selling my not so old Mercruiser 260, drive, and plates

[old rigger]

The reason your 'dealer' might have told you it was pre-alpha unit is because when OMC came out with that drive it was a direct rip-off of a merc unit. Their patents on the alpha had expired and OMC had the Cobra waiting in the wings. It was a nightmare and for every boat we sold with the new Cobra unit it seemed like we had 2 come back for repairs. OMC then came out with the 'new' King Cobra and it was a much better unit. To be honest, I never dealt with the smaller engine combos so I have no idea what gears you're running.
Because of the terrible, god awful reputation, they built in such a short time OMC wanted to show the new lowerunit in a new light and we were asked to build a boat and get a record with the drive...any record so they could use it in their advertisements. So we built a hull for the ETII class. Using a bone stock drive, with a modified nose cone and a mostly stock SMC, low intake manifold, single carb and so on we set the record at I believe 116 or 118mph and change. The record still stands today. Never had a problem with the drive, raced it in the Mississippi race 2 years in a row (1000 miles in 2 days) set the kilo record with it in Parker and raced the enduro there too. Flipped and sunk in the first lap...ruined the hull but the drive was still intact. Very tough.
That's the late Harry Christiansen with the sun glasses on in the second picture and behind the wheel of the boat. He was murdered about a decade after these were taken. Owner of Advantage Boats.
http://img.photobucket.com/albums/v210/flyin-t/advantage1.jpg
http://img.photobucket.com/albums/v210/flyin-t/advantage203-10-22.jpg

[RODE'S WAY BOATS]

The 4cyl gear case is smaller and does use a lower gear ratio Omc did have a cable and a gear issue with the first few years of the production on the Cobra but a majoraty of the problems that they had were cause by people adjusting the cable that did not know or follow the adjustment proceedure correctly. You would be able to get away with putting a V-6 in your boat with out to much hassell but a V-8 would probably be to much for the lower unit. Old Rigger those are some cool pics of harry and his race boat, That was a good man that will be missed for a long time.

[old rigger]

Oh yeah, Joe Rode at Rode's way installed the super nice nose cone on that race boat of ours. Thanks for joggin' my memory.;)

[Chickenlips]

Oh yeah, Joe Rode at Rode's way installed the super nice nose cone on that race boat of ours. Thanks for joggin' my memory.;)
Old Rigger, You being from Long Beach, I'm sure you knew Joe Reath. Is he still in bussiness? He had a guy buy the name of Gary that worked on my motor, I can't remember his last name, was it Schleer or something like that) is he still around.