Logo
FULL SITE MENU

OMC Cobra 57 identification

S

sagacious

New member
"i have an OMC 5.7 Cobra engin

"i have an OMC 5.7 Cobra engine and i have all the numbers off of it. I'd like to know some information on it if anyone can find it. hp/torque rpm band, 4 bolt main, 2 bolt main. year, what it originally came with intake/carb. any chance on knowing what kind of heads? i picked it up yesterday for $50. complete. 140psi on all cylinders. unknown run time.

Front blocking casting number: VO725OAS

OMC model number: 574BPEPWS

OMC Serial number: TO11892O7"
 
I can tell you it's a 1990

I can tell you it's a 1990 model that came with a 4 bbl carb. It would have been rated around 260 HP (at the crank). It's also possible it may have had the King Cobra drive on it with thru hull exhausts.
Max RPM would be in the 4200-4600 range.
 
is this a regular rotation mot

is this a regular rotation motor? my plan for this engine is to put it in my '68 el camino since everything else is standard. im not a fan of the rpm range but im sure its got lots of torque.
 
"yes it's regular rotation

"yes it's regular rotation, they changed the gearing in the outdrive to give them counter rotation. Keep in mind it's a marine engine so the cam in there is going to be similar to a truck."
 
"yea i knew about the cam. thi

"yea i knew about the cam. this is just a daily driver im not looking to blow the doors off. but i am a little concerned, will i be getting worse of better gas mileage with this type of cam? im under the assumption hi torque grunt motors get terrible gas mileage. any thoughts?"
 
"if it was a raw water cooled

"if it was a raw water cooled engine, it may give you grief in the form of continual rad plugging with sand and rust.
Once a block is used in a open cooling system with lake water in the jackets, it's best kept as that.

At least be prepared to do a lot of rad flushes."
 
the only other thing i can thi

the only other thing i can think of... since this is a one piece rear main seal engine.. is it a factory roller motor?
 
Back
Top