90 GT-250 460 engine replacement

[chawk]

My GT-250 ragazza needs an engine overhaul (threw rod). I have the engine on the table and thinking about a horsepower upgrade. If it adds value to a boat like this, then maybe I can justify the extra expense. Just wondering if I should keep it stock or upgrade and if an upgrade would cause any outdrive problems?

thanks chris

[Barry Eller]

My GT-250 ragazza needs an engine overhaul (threw rod). I have the engine on the table and thinking about a horsepower upgrade. If it adds value to a boat like this, then maybe I can justify the extra expense. Just wondering if I should keep it stock or upgrade and if an upgrade would cause any outdrive problems?
thanks chris
Do you have the OMC King Cobra outdrive? Most of the Ford powered boats in that era were OMC. King Cobras are rated to 650HP. As far as adding value to your boat, a boat with a fresh engine that runs is far more valuable than a boat that has a blown engine that does not run at all.:boat: :yippie:

[Avialanche]

Repower the boat with a engine from the GM family, it'll sell alot quicker and for more $$$.
The same goes for Sterndrives, Mercruiser's will sell better than OMC.

[LSUTIGERS74]

CHAWK, I am actually getting one of my 460's out of the shop today. I had oil and water mixed together and the complete engine needed a rebuild. Two bad heads, rewelded the EGR gasket lip on the intake, new cam, rods, valves, lifter, bearings, freeze plugs, pistons, and a few other minor parts. Also had the block shot peened, heat treated, jet washed, pressure tested, decked, bore aligned, and bored out 30 thousandths. I will put it this way, it is not cheap to rebuild an engine this big and parts are scarce for the marine application. Just be careful on the cams and rods, there is a marine spec. I still have got to get my engine put together on Tuesday and Wednesday. If you are looking for another block close by, I see you are in Tupelo, my guy has another D9TE block (marine block cast). The shop is called Northside Engine Parts and Repair, they are located in Lafayette, LA. I searched high and low and their were not too many places period that even had the block, most were in the northwestern part of US. If you want you can call my cell, just PM and I will give you my cell number.

If at all possible try and upgrade to the Chevy there is just so many more aftermarket parts and availability but as the other have said it will cost.

[chawk]

The chevy conversion does sound enticing, but my money tree just hasn't bloomed this year. It seems everybody I talk to at least knows a little about BBC rebuilds and folks just kinda shrug when I ask "what about my big block ford.
Unless I get a donor motor and outdrive, I'm gonna stick with my 460 and king cobra. I talked to two local marine shops and they both recommended the same guy to rebuild my engine. I then talked to this guy and he seems to have some marine engine rebuild experience. But I still want to know what will work best for my size boat (25 ft and 4800 lbs) with the 460 and the king cobra. I will take it to him tommorow and I want to upgrade the hp a little without incredible expense. So what is the number 1 or 2 things that will help this size boat with a 460?
thanks

[Barry Eller]

What will help your 460 Ford the most with out spending a lot of money? Besides rebuilding it, threw a rod? Better exhaust, better intake manifold, better camshaft, better ignition, better propeller, better carburetor,etc.
I have a 1993 22 Classic OMC King Cobra, however I have BBC/502 CID. I think if you can afford to do all it takes to rebuild your Ford, GM power may be less than that. Check for a used take out engine. I bought a New GM Base 502 from www.1800runsnew.com. These are New long blocks that you will have to complete, but it will be all new.
Here is a photo of my finished engine.

[chawk]

Just for argument sake, what is involved in making a chevy engine work with the OMC Cobra outdrive? and cost to adapt?

[Barry Eller]

Just for argument sake, what is involved in making a chevy engine work with the OMC Cobra outdrive? and cost to adapt?
For starters, the bellhousing is different,coupler may be different also. There are a lot more OMC's in marina salvage yards that you may be able to find the used parts to make the change more affordable. The King Cobra is a great drive,almost bullet proof. I built my 502 with new intake,cam upgrade,new exhaust, crossover cooling system, for around $7000.00.plus labor for things I couldn't do. Like pulling out the old 454 and installing the new block.
What are the $estimates on rebuilding your Ford?

[MOP]

The one thing that may be hard to find is a OMC/Chev bellhousing for the swap, that would be a good move and add value. Depending on your pockets you can find a lot of BBC's with varied HP.

Phil

[chawk]

I can get this rebuilt to stock marine for about $1800 if no hiccups occur. So I was debating about spending more to get more hp. The 5k to 7k is out of my budget right now. I just figured if I had, it out, I would beef it up a little.

[Barry Eller]

I can get this rebuilt to stock marine for about $1800 if no hiccups occur. So I was debating about spending more to get more hp. The 5k to 7k is out of my budget right now. I just figured if I had, it out, I would beef it up a little.
Fix what you have and enjoy your boat!!! That is what is important.:yippie:

[conyo]

Hey Chawk,
I am currently in the last stages of installing my rebuilt ford 460. If I could do it all over again I'd buy a 496magHO and Bravo XR drive package (23 grand CAD) Anyways my new 460 has the edelbrock power pakage, new pistons, rings, cam,roller rockers, full msd marine ignition, high flow electric fuel pump, Hi-Tek full stainless jacketed exhaust manifolds, 4" side exhaust with hardin inline silencers (bullcrap! its still loud really loud) approx 8k worth of crap. Will have 525 to 550hp and its going in my GT-250. Also I upgraded the closed cooling system and added a crank mounted auxillary raw water pump to increase the flow through the heat exchanger. Oh yea, and put in a dual raw water strainer. The guys who dry fitted my engine are having a bet on weather I'm gonna blow up my King cobra. Reason being, there are three versions of the cobra. First is the regular cobra (small holes for the raw water pickup,) second, the first king cobra which looks like a regular cobra upper but a larger lower with slot style water pickup. And third the beefier king with a hump on the upper (cone clutch). Reason I'm telling ya this is cause I got the second version. Who knows what'll happen with the leg? As long as I don't hole shot the boat I should be ok. I was planning on upgrading to a Bravo One XR in the winter but their is no known available bellhousing to mate a NEW style XR with an OMC (ford) 460. ANything can be fabricated. I have heard that a Volvo Penta leg might bolt on to replace the King. As I said earlier If I could do it all over again I'd go with a Merc package. Of all the fords the 460 is the most expensive for parts/upgrades. I cant tell you how many times I saw through my net searching the cheaper deals for GMs/Chevs. Plus the cobra stuff is becoming harder to find and more expensive. If ya need anymore info/pics I'd be happy to share...

[conyo]

Oh...I forgot, I also installed a pre-luber oil system...on friday night we fired it up to break in the new 460. Within 6 minutes heard a clacking sound on one side! And misfire through one of the side exhausts. Pulled the valve cover to see if roller rockers were hitting the valve covers. Nope as we suspected... pulled the intake manifold and cam and lifters fried!!!!!!!! Big pain in the ass!!! A word of caution for those rebuilding their motors "do not use flat tappet cam and rockers! invest in a roller cam setup or break in your motor outside the boat. This is really dissapointing to invest all this TIME and money only to have a major failure...in mid summer!!!! Comp cams are bull**** their only warranty is they'll send you a new cam and lifters...what about the 500 bucks to remove the motor and another 1200 to dryfit and align...again! I had full oil pressure before the start and the guys who built my motor are PRO's who have been doing this for 25 odd years. They are nice enough to correct my problem since they recommended the Comp cam. Well now I'm gonna go full roller cam cause I'm sick of wasting any more friggin time!...till next time...