mods for 5.0 omc engine?

[MountainManMyke]

Hey all, i have a 20' 1990 four winns horizon 200. The thing has a omc cobra 5.0 for a heart. I love the boat, motor runs mint, can get about 42 mph out of it. My questions are in regards to doing mods to this boat. I have a vortec 350 in my shop i am going to rebuild this winter. I am wondering what kind of intake, carb, and cam i should run and what kind of exhaust? Also is there anything i should watch out for when doing this swap? I know ppl are going to say its not worth it and bla bla. I love wrenching and tuning and the boat is in mint condition. Any advice would be appreciated. Thnx

 

[vasy]

I'd not screw with the current engine but if you have another one to toy with, why not, always good to have something to do in the winter.
Just don't forget that you may need to adjust leg gearing to account for more power.
Who knows, you maybe get it all the way up to 48 mph.

 

[MountainManMyke]

I think a vortec 350 would make a significant difference over a stock non vortec 305

 

[vasy]

305 is rated at what, below 200hp and a well tuned 350 should be getting 300ish hp. So some good jump.
Boat should become more alive with it, just watch that outdrive can handle it.

 

[Bondo]

I have a vortec 350 in my shop i am going to rebuild this winter. I am wondering what kind of intake, carb, and cam i should run and what kind of exhaust?

Ayuh,..... Leave the 5.0l alone, 'n just run it as is,.....

Tell Us more 'bout yer 350,.....

What year/ vintage block, 'n heads,..??

What's yer Budget,..??

Over-bore it .030, deck the block, drop in a stroker crank, 'n D-dish pistons to mirror the Vortec combustion chambers,.....
Dial in the quench to .042"/ .045", 'n compression ratio to just under 10:1,....
Top it off with an Edlebrock 4bbl .carb,....

You'll have a 383 stroker,... kinda like a box of dynamite on the other end of the throttle cable,....

 

[bruceb58]

If you drop the 350 in it, I wouldn't bother with the gearing of the drive. Go up a couple inches of pitch and take it easy accelerating so you don't blow the drive.

 

[MountainManMyke]

I may just leave the 5.0 alone and keep the 350 vortec for my 47 chevy truck. What are some mods combos that i can do to the 305 to wake it up a little bit? Budget is around $1000. Thnx

 

[MountainManMyke]

The 350 is all stock. Out of a 1996 gmc 1500 half ton. Was going to freshin up the bottom end and give it a hone, possibly throw a cam/intake/ carb onto it.

 

[Bondo]

What are some mods combos that i can do to the 305 to wake it up a little bit? Budget is around $1000. Thnx

Ayuh,.... Ya haven't told Us anything 'bout the 305,.....

Has it got a 2bbl. or 4bbl. carb,..??

Where do ya boat,..?? saltwater or sweetwater,..??

 

[MountainManMyke]

The 305 is all stock with a 2 barrell. I live in canada and i boat all around northern canada lake superior...... all fresh water.

 

[Bondo]

Ayuh,.... So slap a 4bbl carb on it, 'n be Happy,....

It'll give ya 'bout 20 hp on top end,...