INJECTORS

Perfect Power Articles.

 

Injectors are electromagnetic devices, like a valve, which opens and closes with some electric pulse. The pulse is issued from the on-board engine computer, or engine control unit (ECU). Then length of the injector opening determines the amount of fuel the engine gets. The exact amount depends on the Air Fuel Ratio (mixture).

 

IN PRINCIPLE THERE ARE TWO TYPES OF INJECTORS :

 

  • Direct and Manifold injectors.


Direct injectors inject the fuel directly into the cylinder. This requires a very high fuel pressure because the cylinder pressure is very high. Because of this it is very hard to open the injector and a very high voltage is used.

Manifold injectors inject the fuel into the manifold, where it mixes with the air. These injectors are cheap to come by, and various sizes and flow rates are available. Again, these injectors can be classified in to two categories:

 

  • High impedance: Usually they have approx. 13 Ohms.
  • Low impedance: Anything below 4 Ohms, normally 1 Ohm.

 

High impedance injectors can be handled by all of Perfect Power products directly. However low impedance injectors require a special “Peak and Hold” driver, which is separately available.

Why does a low impedance injector require a different driver? The answer is simple: The activation coil gets to warm, which makes the fuel boil and evaporate, and instead of fuel the engine gets vapor and runs lean.

 

ALL THE FOLLOWING PRODUCTS CAN HANDLE HIGH IMPEDANCE INJECTORS :

SMT8 piggy-back unit
SMT8L piggy-back unit
SMT8T piggy-back unit
XMS4 Stand Alone range (Discontinued)

 

THE FOLLOWING PRODUCT HANDLES LOW IMPEDANCE INJECTORS :

XMS-PH

 

OTHER TUNING ARTICLES WORTH READING :

Lambda Tuning
Fuel Consumption
Extra Injector Tuning

 

VISIT THE FOLLOWING LINKS FOR MORE INFORMATION ON LOAD SENSORS (AMP) :

Product Manuals
Application Notes
FAQ’s