7.4L/8.2L Marine Long Block Engines

New and Remanufactured Longblock……(Pricing)

Help me find my Serial Number or Block Casting Number (Read More)

TERMINOLOGY:
There are three different types of the GM Marine based V8 7.4L 454 cid Marine Engines which were used by Mercrusiser, Volvo Penta and Crusader. Some of these engines are interchangeable and with only a few changes. However the NEW version of this longblock engine is available only for 1987 and up big block Marine Engines. If you are replacing a pre-1987 “Mark IV” engine and you are looking for a direct replacement you will need to purchase a Remanufactured Marine Longblock….(Read More).

There are a variety of different challenges involved with Big Block V8 engine re-powers today since GM and all of the Marine Engine manufacturers quit offering complete turnkey 454 engines several years ago. Now to complicate that even further trhow in the fact that the 496 C.I.D. V8’s were discontinued from GM in 2010 and things really get tough. All of this limited engine availability in combination with the 2010 Emissions Rules (Read More) creates a more complicated re-powering situation to say the least. However this is where PPT steps in and offers you the Technical Expertise needed to repower your boat.

7.4L L29 MPI 1998-2001 NEW Longblock….(Read More)
This Marine Longblock Engine was used only with a General Motors installed multi-port injection (MPI) fuel delivery systems. The L29 longblock utilizes a 1 piece rear main seal, roller camshaft, and oval port heads. This engine was rated from 310 – 330 hp in Marine Applications such as with Mercruiser Engines but this was not the actual produced Horsepower value. The actual horsepower value was closer to 305 hp. When purchased as a Longblock the engine will does not include the intake, flywheel, and water pump. You must use an electric pump.

7.4L 330HP Power Package(No Longer Available)
PPT introduces the 7.4L Power-Pack, the re-power package that gives you what you need. This Power-Pack is a NEW 330 horsepower GM Gen V/VI base engine, equipped with a complete fuel system as well as the ignition system. By using existing hardware, bell housing and exhaust systems, installation is made simple.

7.4L 330hp 1987-2002 NEW Longblock….(Read More)
This long block engine was used with a 4 BBL carburetor, EFI (throttle body), and a Mercruiser factory installed multi-port injection (MPI) fuel delivery system. It has a 1 piece rear main seal, roller camshaft, and oval port heads. This engine can be used for pre-1987 applications but a modification must be made for the electric fuel pump. The engine does not include intake, flywheel, or water pump.

454 MAG 385 hp 1987-2002 NEW Longblock….(Read More)
This is the best way to distinguish it from the other 7.4L engines is that it has rectangular port heads and a high performance camshaft. They are the same heads that are used in the 8.2L 502 cid engine. The engine has a 1 piece rear main seal, roller camshaft, and must use an electric a fuel pump. The engine does not include an intake, flywheel, or water pump.

454 MAG 392 Hp Power Package (No Longer Available)
This Power-Pack is the perfect repower option for pre-1992 base 7.4L applications or for even for 1992 and up applications looking to upgrade from a 310/330HP 7.4L to the higher HP and higher torque 454 MAG 392 HP engine. Equipped with a complete fuel system as well as the ignition system. By using existing hardware, bell housing and exhaust systems, installation is made simple.

502 MAG 415 Hp NEW Longblock….(Read More)
This engine uses the same heads that are used with the 7.4L 454 cid magnum engine (rectangular intake port). The engine has a 1 piece rear main seal, roller camshaft, and must use an electric a fuel pump. The engine does not include an intake, flywheel, or water pump.

502 MAG 415 Hp Power Package (No Longer Available)
This Power-Pack is the perfect repower option for pre-1992 base 7.4L or 502 applications or for even for 1992 and up applications looking to upgrade from a 310/330HP 7.4L to the higher HP and higher torque 502 MAG 415 HP engine. Equipped with a complete fuel system as well as the ignition system. By using existing hardware, bell housing and exhaust systems, installation is made simple.