Emag harmess resistance

[Eric12]

Emag harness resistance

I just bought two emags and two emag brand harnesses. All of the leads measure approximately double the recommended 180 ohms per foot stated in the emag manual. I suspect this is not really a problem, but does anyone know?

 

[Ironflight]

You can very well have miss-firing with the wrong resistance - I know, I’ve had it - but I don’t know what the tolerance is.

 

[Carl Froehlich]

I suggest you first verify the accuracy of whatever you are using to measure resistance. If good, a call to Brad at eMag is in order.

Carl

 

[Eric12]

Thanks Paul. I'll check with emag. When I searched for lead kits from Accel and others, the lowest I found was 350 ohms per foot, so I bought the emag brand. All 8 emag leads measure 350-450 ohms per foot.

 

[lr172]

Thanks Paul. I'll check with emag. When I searched for lead kits from Accel and others, the lowest I found was 350 ohms per foot, so I bought the emag brand. All 8 emag leads measure 350-450 ohms per foot.

That sounds about right for plug wires. The plugs have 5000 ohm resistors in them so what you have here is no issue. Remember that we are dealing with around 30-40,000 volts coming out of the coil, so this level of resistance is inconsequential. Half this voltage will jump an 1/8" air gap (infinite resistance) and still spark the plug. That's what was happening inside an old school distributor, as well as inside a mag.

180 seems too low to be accurate unless they are metal instead of carbon infused string and that is rare for automotive.

 

[Eric12]

Thanks LR. That's what I was thinking. Not sure why Emag specifies 180ohms per foot.

 

[riobison]

On my light speed I had 1 wire that was open (but still fired the plug). Checked the other 3 and they were between 50 and 68 ohms after 500 hrs.

Bought 1 new MDS wire cut to fit and it was 435 ohms at 16 inches

MDS advertises 50 ohms a foot and I didnt see it. We checked some other wires and they were still 400 to 500 ohms a foot.

https://www.holley.com/products/ignition/spark_plug_wires/msd_spark_plug_wires/

Not sure why the huge discrepancy.

Tim

 

[Dad's RV-10]

Are most using automotive wires (MSD or similar?), cutting to length and terminating?

Or do you use the wires sold by E-Magair? If so, do the E-Magair wires come cut-to-length and terminated?


EDIT: Just found the wires on E-Mag's site. They are pre-terminated.

 

[Brantel]

I built both my harness’s using Emag Air’s wires and never had an issue.

 

[riobison]

Are most using automotive wires (MSD or similar?), cutting to length and terminating?

Or do you use the wires sold by E-Magair? If so, do the E-Magair wires come cut-to-length and terminated?


I cant imagine that there's a difference but that is a good question.

 

[Bob Martin]

Thanks LR. That's what I was thinking. Not sure why Emag specifies 180ohms per foot.

FYI Emag's NEW wires and spec'd at 40ohms per foot!
Yep, I ordered a new set and ohm'd them and was shocked...called Brad, he said new wires, new spec's and he hadn't updated the pdf install manual.