Replacing your 1967-1985 5.7L

The 5.7L 350 cid GM marine engine has been used in the marine industry since 1967. The engines can be easily distinguished in that they have a 12 bolt pattern intake manifold, 2 piece rear main seal, and a mechanical fuel pump pad. The engine is rated at 260 hp.

Opposite Rotation Engine

Replacing your 1986-1995 5.7L

The 1986-1995 5.7L engine is a 1 piece rear main seal engine as compared to the 2 piece of the pre-1986 5.7L, and also has a roller camshaft. The intake is still a 12 bolt pattern and has a fuel pump pad for a mechanical fuel pump. The center 2 intake fasteners differ from the pre-1986 engines in that these are not angled at 45 degrees as the other 10 fasteners. These center 2 fasteners are in nearly a vertical position as they have to clear the exhaust crossover in the manifold. The pre-1986 intakes have all 12 fasteners at 45 degrees. The engine is rated at 270 hp.

Replacing your 1996 and up 5.7L (Vortec)

The latest marine 5.7L engine is a 1 piece rear main seal. The easiest way to distinguish this engine is that is has a 8 bolt pattern intake manifold and uses a electric fuel pump. The engine has the "Vortec" style heads. The engine is rated at 300 hp.

Partial Engine Packages (Longblock + Carburetor + Ignition)