Have a question on Marine 454 big blocks? I am new at marine stuff, But very old car guy. After tearing down some marine engines I do not see anything different in the engines besides the cam size? Is this true? I have also been told they put a coding on the inside of the water jackets, this is true? I have a 89 Chevy Gen V big block in a Baja, I want to take out the 365 Hp Mag engine and put a stock 330 Hp engine in. I see some 454 big block on craigslist list, but they are out of older trucks. Does it matter what year block and heads I use and if it is a 4 or 2 bolt. Like I said it is to make a 330 Hp engine.

I am new also, but from what I have read and seen the big difference is Cam and core plugs in marine apps are brass instead of steel. As far as carbs and dist. those are totally different from a safety standpoint.

Its not so much the "Engine" that is so different. Its how you build it.

The parts are pretty much the same depending on what you have, like a 330 is just standard cast crank, 3/8 rods, and oval port heads, cam will be small and different from a car, freeze plugs will be brass, mainly in higher HP engines things are different about how it is built, not so much the parts used..liek most marine engines run a little more clearance then a car...but parts are the same.