this will be a fun one..

[jimmy wise]

ok so i got a 2004 cobalt 246, no motor or drive it was 7.4 bravo3. so can i put my 383 stroker in front of a bravo three? what other drive will fit in its place? the 383 is built for super charger if needed. i have time but i was looking for options......496 bravo 3 would be sweet but unless i find a bucket of gold ill be awhile saving

 

[thumpar]

I think you will have to move the engine mounts to make it fit correctly with a SBC. How was the 383 built? Boat motors are built like truck motors. If it has an overlap cam or built for high revs it may not work well. You could get a 454 truck motor at a junk yard and change the core plugs to brass. It will be a spendy project no matter which way you go. You will need all the externals for marine use unless any of it is left.

 

[achris]

ok so i got a 2004 cobalt 246, no motor or drive it was 7.4 bravo3. so can i put my 383 stroker in front of a bravo three? what other drive will fit in its place? the 383 is built for super charger if needed. i have time but i was looking for options......496 bravo 3 would be sweet but unless i find a bucket of gold ill be awhile saving

If the transom plate and gimbal ring are still there, any Bravo drive will bolt straight up. As for engine, ANY engine can be made to fit, even a 3.0 litre. A few things you would need to consider, along with what thumpar said, are ratios and engine beds.

 

[Scott Danforth]

get a 454 truck motor from a you-pull-it and buy a 4.5" strok crank.....bang a 496 long block for about $2500 depending on what else you need.

or simply get the truck motor and build a 468 for about $1500

 

[alldodge]

ok so i got a 2004 cobalt 246, no motor or drive it was 7.4 bravo3. so can i put my 383 stroker in front of a bravo three? what other drive will fit in its place? the 383 is built for super charger if needed. i have time but i was looking for options......496 bravo 3 would be sweet but unless i find a bucket of gold ill be awhile saving

The Cobalt is a heavy boat and weights in at 4100 pounds. I would recommend using a BB because you will want the torque. The SB will produce enough HP but they lack the torque to get it out of the whole easy. Using a Bravo 3 drive will help if using the SB, many manufactures place the B3 with the small boats on a heavy boat for this very thing. Example, my Rinker weights 3800 and has a B1 drive. Another has the same boat (2000 model) with an EFI 350 and B3. His opinion the boat does fine but is slower coming up, and pulling a skier is more so. The old saying, there is no replacement for displacement.

 

[muskyfins]

If you look around you can find either quality parts that someone has removed from a boat or whole boats with serviceable parts and then scrap the balance. There's a guy in Wisconsin that buys old boats and removes all the serviceable parts. He's got tons of stuff. Not really a "junkyard" just some guy making spare cash on the side.

I'm not necessarily making the case for a particular engine, but here's an entire boat for $1500. Pull motor, keep or sell any serviceable parts, sell trailer. (hell-I'd give $200 for the trailer) scrap the balance.

1991 Sea Ray 225 BR -xxx

91 Sea Ray bow rider, 24' overall, with 7.4 Bravo 1.
Handy man special. Nice winter project.
Needs: Floor, Stringer rebuild
Runs perfect, low hours on motor for a 91, pulls multiple skiers and tubes with ease, tops out at 45 mph with 4-6 on board. Used it up until 3 weeks ago. Still good as it sits for a few more years use in current condition. Seats and trim in good shape as photos show. Sea Ray quality shows here.
Divorce forces sale
Web search shows these sell for $7000-8000 in decent shape
$2500 in wood, fiberglass and carpet puts it above that

 

[jimmy wise]

yea i have time. i have a mr drive that is fresh. thats what i would run with sb. i have everything from mercuiser for small block except for manifolds...

 

[thumpar]

I don't know that I would put an Alpha type drive, especially an older one, behind a 383. Be easy on the right hand with it.

 

[achris]

yea i have time. i have a mr drive that is fresh. thats what i would run with sb. i have everything from mercuiser for small block except for manifolds...

You can not bolt an MR (or any Alpha style drive) to a Bravo transom assembly... Only drive that will go on a Bravo transom is a Bravo.

 

[Walt T]

I'd stick with a BBC and no way would I use a junkyard motor with rebuilding it. All the mounting holes and any hardware wiill all fit the big block but you'll have to modify everything for the small block. ECM and electrical would all be different. Good luck. I don't know what all parts you have with the boat but it's gonna be a project. Why was the boat stripped in the first place? You mentioned "Bucket of gold" sorry but you're gonna need it. I turn away jobs like this.

 

[Tail_Gunner]

I'd stick with a BBC and no way would I use a junkyard motor with rebuilding it. All the mounting holes and any hardware wiill all fit the big block but you'll have to modify everything for the small block. ECM and electrical would all be different. Good luck. I don't know what all parts you have with the boat but it's gonna be a project. Why was the boat stripped in the first place? You mentioned "Bucket of gold" sorry but you're gonna need it. I turn away jobs like this.

What Walt is pointing out here...the ecm is a very big deal, I believe that year and vintage makes the ecm priority tech...read very expensive to reprogram about 12-1500 id assume

 

[jimmy wise]

ill have to see if the ecm is there, may have to buy another doner. the boat ended up on the rocks and damaged the bottom. the drive is all missing. my mr is complete but i am afraid to use it to. 898 is what it was from. i have no efi

 

[jimmy wise]

what is the difference between a bravo 1 and 3? where is the computer located

 

[achris]

what is the difference between a bravo 1 and 3? where is the computer located

Engine-wise, nothing. The difference is the lower housing on the drive. Single prop vs dual counter-rotating props on the same 'shaft'. ECM should be mounted on a plate which is mounted to the port exhaust elbow.

 

[thumpar]

What do you have now as far as engine/drive parts on the boat? Do you just have the keyhole in the hull or it the transom assembly still there? What about wiring? Pics would help.

 

[HT32BSX115]

ok so i got a 2004 cobalt 246, no motor or drive it was 7.4 bravo3. so can i put my 383 stroker in front of a bravo three? what other drive will fit in its place? the 383 is built for super charger if needed. i have time but i was looking for options......496 bravo 3 would be sweet but unless i find a bucket of gold ill be awhile saving

That 383 might be fine if the camshaft is similar to a marine (read truck/RV) cam.

If it's a "Hotrod" cam, you'll have reversion problems.

That boat is big and heavy, It's going to be somewhat "doggy" out of the hole with an Alpha or Bravo I (that why they put the B3 in them)

I would sell the 383 and get a junkyard 496 or 454 to rebuild ..........or rebuild the 383 to make max torque at less than 5000 RPM.

Cheers,


Rick

what is the difference between a bravo 1 and 3?

Bravo I has only 1 prop!

 

[Tail_Gunner]

ok so i got a 2004 cobalt 246, no motor or drive it was 7.4 bravo3. so can i put my 383 stroker in front of a bravo three? what other drive will fit in its place? the 383 is built for super charger if needed. i have time but i was looking for options......496 bravo 3 would be sweet but unless i find a bucket of gold ill be awhile saving

Could you be a little more spefic on this 383...built for a super charger does it have forged internal's? What is compression ratio now it must be low and the cam duration how much overlap does it have. You say a bucket of gold that is what it would take to build a supercharged 383 with mpi and that's ok. Lay out what you have and your budget that will focus the conversation a bit. There's a two way's to tinker with a boat .....big money who care's or ask question's and be spefic that will say you thousands.

 

[jimmy wise]

yes it has forged internals, its not a huge cam close to rv. 7 to 1 on compression. it would need boost im sure. all my boat stuff is from an 898 setup 305 small block

 

[jimmy wise]

i dont have it hear to see wiring but ill get photos

 

[Bondo]

yes it has forged internals, its not a huge cam close to rv. 7 to 1 on compression. it would need boost im sure. all my boat stuff is from an 898 setup 305 small block

Ayuh,.... Ya need the cam's numbers, lift, duration, etc,.....

at 7:1 yer gonna need the blower to get the boat to move,...