Injectors

Injector Flow

• What size injectors do I need?
  • You can figure this out using our CFI tool here

Types of Connections

Types of Outlets

One thing to consider when purchasing injectors is the spray pattern. This difference is most noticeable when comparing older <1990 injectors to newer >1990 injectors. The older injectors have a single exposed pintle (Fig. 1), whereas more modern injectors tend to have an internal pintle with a patterned nozzle (Fig. 2) that helps better disperse fuel into the intake air.

Fig. 1 — an exposed pintle.

Fig. 2 — a quad-hole nozzle.

It’s evident just from the physical difference that the spray pattern will differ. In the below image (Fig. 3) you can see a comparison of both of these two patterns.

Quad hole nozzle injector (left) vs. single hole nozzle injector (right). Notice the more dispersed pattern of the quad hole unit.

The patterned nozzle will provide better overall fuel efficiency which can lead to improved fuel economy and power output while also minimizing knock potential. Upgrading injectors to a patterned nozzle is a worthwhile upgrade for any vehicle equipped with an exposed pintle design.

BMW Injectors

So what do you need to use for your BMW? This depends on your year and engine. For pre-2014 vehicles it's most likely going to be a "long" body injector with EV1/Jetronic connection. There are some exceptions, such as the M44B19 which uses an unusual injector and requires an adapter for common injectors to be used. With direct injection and diesel engines, injectors vary drastically depending on engine.