Marine Head vs Automotive Head Mercruiser 5.7

[synergy141]

My Mercruiser 350 dropped a valve guide on one of the cylinders causing a bunch of damage. So I need a new head...

My casting number is: 14096217 which is a year 1955-86 GM head. If I bought a used head off any gm 350 between those years would that work? Or are marine heads totally different?

 

[Howard Sterndrive]

My casting number is: 14096217 which is a year 1955-86 GM head. If I bought a used head off any gm 350 between those years would that work? Or are marine heads totally different?

that's not what I have.
87 - 96 head 5.7

does it have perimeter valve cover bolts? all 55-86 have perimeter. 87- on if you have center valve cover bolts.

at the end of the day, casting numbers are often not the best thing to reference - better to start with your engine year and model.

 

[achris]

Personally, I'd replace the heads as a pair... Then there is no risk of an imbalance.

 

[NHGuy]

I disagree with Howard, casting # gives you runner and combustion chamber volume, valve size. the whole deal. Look up the details and get a head that mimics the good one you are keeping.
Marine heads are not different, but they do use a specific gasket.
BTW howard I dig your screen name.

 

[Howard Sterndrive]

I disagree with Howard, casting # gives you runner and combustion chamber volume, valve size. the whole deal.

it didn't even get him the right decade. And if he is looking at 55-86 like he says, he would have to look for steam holes (400) etc. Casting numbers can have different machining and even valve sizes.

 

[Bondo]

it didn't even get him the right decade. And if he is looking at 55-86 like he says, he would have to look for steam holes (400) etc. Casting numbers can have different machining and even valve sizes.

Ayuh,.... I agree, But,..... The same castin' number heads, at least start out as identical pairs,...

Personally, I'd never mix a set of heads, with Different casting numbers,....