Difference in high and low inpedence injectors?

[V SICKS]

Would someone shed some light on the high and low impedence injectors. Which ones are best and which are not so good? THANKS..mike

 

[RmvBfrFlght]

Neither is better or worse then the other. They are just different. A high impedance injector (also known as 'saturated') will measure between 12 and 16 ohms (use a DVM). They can be used with the stock GN '148 ECM. The Motron 60#'ers are a good example of larger high impedance injectors.

The low impedance injectors (also known as peak-and-hold {PnH}) measure about 2.4 ohms (again, use a DVM). In order to run them with a stock ECM the drivers need to be upgraded. They tend to open faster then a saturated injector. But can also be more erratic in fueling. The faster opening time can be an advantage when RPM limits the duty cycle.

RemoveBeforeFlight

 

[bison]

Low impedance are desireable when you have a high horsepower per cylinder application. They can be short pulsed much easier to allow cleaner idle and low pulse width control. They draw more amperage since the resistance is lower and the voltage is constant.

 

[TurboBob]

The low impedance injectors ......... can also be more erratic in fueling.

RemoveBeforeFlight

Not in my experience

Bob

 

[bison]

Not in my experience

Bob

I agree Bob. I found just the opposite.

 

[RmvBfrFlght]

What can happen when PnH's are installed is that they end up over sized for the application. Then the idle PW becomes too small for even a fast opening injector with the resultant erratic fueling.

In truth this isn't an issue with the injector, but an issue of the user installing too large of an injector. Which is done because the user is thinking that being a PnH they can get away with it. Which comes back to: they can have erratic fueling.

RemoveBeforeFlight