5.7L Technical

Oldsmobile Diesel Injectors

There are two types of injectors used on the Oldsmobile Diesel engines...Pencil Injectors and Poppet Injectors (also known as micro injectors).For those who are not aware and those who have noticed that the Injectiors used on Olds Diesel engines are unlike the ones used in other auto-diesel engines..thats because they really wherent for automotive use, but for agricultural applications..The injectors have differnet specs of course in order to meet the needs of that engine, but basicly, They are tractor injectors. The injectors are also the key to the excellent economy. Unfortunatly, the efficient tractor injectors are about twice the price of the conventional Bosch type injectors found in other Diesels such as Mercedes, Volkswagen, 6.2 and 6.5 GM Diesels, as well as the International 6.9 and 7.3 Diesels found in Ford pickups.
Pencil Injectors where used in the early years of Olds Diesels. They where used from 1978-1979 in car engines...Trucks powered by the 350 Diesel had the pencil injection system until 1982, when the 6.2L Diesel was the new Diesel Option for light trucks. The injectors are about 4" tall and very thin..They are held in by a bolt and clamp, and have an opening pressure of around 1800 psi. The 4.3 V8 Diesel (79'-80') also had pencil injectors.

Poppet Injectors are the more common injection system, introduced in 1980 car engines, and used untill 1985, when all Olds Diesel production was discontinued. The poppet, or "micro injectors" are rather small in size compared to other auto-diesel engines of the same time. Similar in size of a spark plug..the poppet injectoralso screws into the head, unlike the pencil injector..which clamps to the head. These have an opening pressure of about 1225 psi. (1980-83) and 1000 psi. (1984-85).

4.3L V6 Diesels used poppet injectors through out its entire production (82'-85'). 5.7L and 4.3L V6 Injectors are identical by sight, the difference it the opening pressures, which are about 1000 psi for the 4.3L, same as the 84-85 5.7L Injectors, but can be identified by the color band located between the upper and lower half of the injector..Blue for 84-85 5.7L, and Red for 4.3L Diesel V6. Installing 4.3 Injectors on a 5.7 would give lower power to the 5.7, but listen up 4.3 V6 Diesel folks...Installing a 5.7 Injector on a 4.3 Diesel V6 would bring a power gain. I would say almost 15 horsepower!