6V92TA or 8V92TA Detroit with marine exhaust manifolds. Will try to get a picture up. In the smaller class a inline six 292 Chevy stovebolt with 2 carbs and headers.
Every one of the Miller and Miller/Offy engines were just a piece of art, as were the 30s Cadillac V8, V12 and V16 along with other senior cars.
Here's a little history on the boat engine, my favorite Miller.