One might think that direct port fuel injection is new. Realistically it has been around since 1952, at least in the automotive field. Originally intended for aircraft, assuring consistent fuel delivery at all altitudes. As an example, the engine for sale I purchased for my 1970 911 Porsche has an early less complicated system using direct port fuel injection.

Direct port fuel injection, as opposed to throttle body fuel injection and Vortec fuel injection is where the injector, injects the fuel directly into the cylinder. The newer systems are very complex (as you might imagine) and use the ECM in conjunction with a series of inputs to deliver the exact amount of fuel for the situation.

The major benefits of direct port fuel injection are:

1. Ultra lean burn mode is used for light-load running conditions, at constant or reducing road speeds, where no acceleration is required. The fuel is not injected at the intake stroke but rather at the latter stages of the compression stroke, so that the small amount of air-fuel mixture is optimally placed near the spark plug.

2. Full power mode is used for rapid acceleration and heavy loads (as when climbing a hill). The air-fuel mixture is homogeneous and the ratio is slightly richer than stoichiometric, which helps prevent knock (pinging). The fuel is injected during the intake stroke.

There it is, we have discussed vortec fuel injection systems and TBI fuel injection systems. Now that GotEngines.com blog has coverd the three types of fuel injection, you can be a more qualified consumer of engines for sale.