going from 3.8 to 5.7?

[greentahoe]

While my boat is out of commission due to a destroyed upper gears on my stringer outdrive, now might be a good time to think about changing from my 3.8 to a bigger engine, possibly a 5.7. Does anybody have the dimensions of an OMC 5.7 engine/stringer system from the inside of the transom forward, the height from oil pan to flame arrestor, and the width from the outside of each exhaust manifold?
I now have a 4bbl Rochester carb on the 3.8 which is supposed to give me a rated 185 hp. On the 5.7 would I really need a 4bbl carb, or would a 2bbl work well and give better fuel economy? I really don't need more power than I currently have. The main reason for changing engines would be that it is cheaper and easier to find parts for the 5.7 than it is for the 3.8.

 

[Don S]

Re: going from 3.8 to 5.7?

You will need to change your gear ratio in the drive for the V8.

 

[Bondo]

Re: going from 3.8 to 5.7?

IF,....... You were to go thru the Labor of changing to a 350,.............

It would be Easier to just JUNK the Stringer Drive,+ Go with a Newer, Better Drive as well as the Motor..........

Soooo,.............
Can it be Done,.........??.....

Ayuh,........ But, WHY,.??........

The main reason for changing engines would be that it is cheaper and easier to find parts for the 5.7 than it is for the 3.8.

If you want Cheaper,+ Easier,..............
Loose the Stringer Drive............................

 

[DHPMARINE]

Re: going from 3.8 to 5.7?

There are a lot of newer better boats out there.

DHP

 

[whywhyzed]

Re: going from 3.8 to 5.7?

On the 5.7 would I really need a 4bbl carb, or would a 2bbl work well and give better fuel economy? I really don't need more power than I currently have. The main reason for changing engines would be that it is cheaper and easier to find parts for the 5.7 than it is for the 3.8.

never seen a marine 350 w/ a 2 bbl... I doubt you'd save any fuel.

except for rear riser manifolds, 3.8's are a dime a dozen. There's a recently rebuilt 229 in my local paper tonight, complete, from an 83 Monte Carlo for 75 bones...

 

[Don S]

Re: going from 3.8 to 5.7?

never seen a marine 350 w/ a 2 bbl... I doubt you'd save any fuel.

EVERY 350 put out by Mercruiser and Volvo since 98 (I think) has been 2 bbl. If you want something bigger, you go EFI.