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low and high impedance injectors

  • Thread starter Thread starter Foxfan88
  • Start date Start date Jun 19, 2007

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
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Miami, Ok
Jun 19, 2007
#1
  • Jun 19, 2007
  • #1
what is the difference b/w low and high impedance, i have heard the term but never knew what it meant
 

Aryan15

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Sep 22, 2003
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Jun 19, 2007
#2
  • Jun 19, 2007
  • #2
Impedence is a combo of resistance, inductive reactance, and capacitive reactance measured in ohms. I've heard that low impedence injectors require more current but open quicker and vice versa for the high impedence but im not sure.
 

RacEoHolic330

I like to dress like a pretty girl
15 Year Member
Mar 4, 2003
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Allentown, PA
Jun 19, 2007
#3
  • Jun 19, 2007
  • #3
As said above, impedance is basically a measure of resistance. Low impedance injectors average about 3 ohms of resistance each while high impedance average about 12 ohms. The less resistance there is, the more current flows through the injector.

Stock injectors are high impedance. The biggest high impedance injectors I've ever seen are 60lbs/hr. The benefit of low impedance injectors are that they can flow a lot more fuel than high impedance ones without causing as many problems in regards to startup and idling. Low impedance injectors go as high as 160lb/hr.

The thing with low impedance injectors are that they need a driver to work properly. That extra current flowing through them causes a lot more heat within the injector. The driver basically consists or resistors and other components to bleed off the heat caused by the excess current. Without the driver, the ECU will eventually blow after only a few minutes.
 

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
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Miami, Ok
Jun 19, 2007
#4
  • Jun 19, 2007
  • #4
so the more current that flows thru the injector, the more fuel it dumps out?
 

Black1987Stang

Active Member
Aug 22, 2004
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Jun 20, 2007
#5
  • Jun 20, 2007
  • #5
Foxfan88 said:
so the more current that flows thru the injector, the more fuel it dumps out?
Click to expand...

From how I look at it it takes less time to saturate the coil (fully energize for it to raise the pintle and squirt the fuel) inside the low impedance injector which will make it open faster, quicker response etc. Less copper winding inside maybe? what's the actual difference on the inside anybody know? Correct me if Im wrong, I like learning. I always used to think injectors were all complex and fancy but there just a little needle to let fuel out operated by a magnetic coil.....which is just ground operated by the ecu. I'm curious to know what the difference is from say a 24lb. injector and a 30lb. injector, different windings, inside are bigger for more flow? I got no idea, if anybody knows I'm curious to know. Sean
 

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
Jun 20, 2007
#6
  • Jun 20, 2007
  • #6
Stock injectors are high impedance. The biggest high impedance injectors I've ever seen are 60lbs/hr. The benefit of low impedance injectors are that they can flow a lot more fuel than high impedance ones without causing as many problems in regards to startup and idling. Low impedance injectors go as high as 160lb/hr
Click to expand...
so what gives the low impedence injectors to be capable of 160lbs/hr
and say you have a low impedence 42lber and a high impedence 42lber what would be the differences.

and what do you mean exactly by less idle and starting problems. what the low impedence injs to do this?
 
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