Minimum guage of wire for coilpacks?

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ion332
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Minimum guage of wire for coilpacks?

Post by ion332 »

Ok, I am going to do a dual trigger w/ the edis coilpacks.

What is the recommended minimum wire guage? I prlly should quit being so lazy and just calculate it but I figured someone here would know offhand.

Thx in advance
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woh
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Post by woh »

You'll find the recommended wire gauge here plus some comments on wire selection:
http://www.megamanual.com/v22manual/mwire.htm#safety

The coil should draw about 5-6 amps max, so a wire size of 20 or 18 will be just fine.
thedge
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Post by thedge »

woh wrote:You'll find the recommended wire gauge here plus some comments on wire selection:
http://www.megamanual.com/v22manual/mwire.htm#safety

The coil should draw about 5-6 amps max, so a wire size of 20 or 18 will be just fine.
For an 8 foot wire run at 7 amps, a 20 gauge wire is going to have a voltage drop of 0.6 volts and an 18 gauge will have 0.4 volts. That is a hell of a lot IMHO, especially for something like coilpacks that are voltage dependant.... This more than doubles at 15 amps, for the common wire to GM coilpacks...
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woh
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Post by woh »

The current in the coil will likely be less than the 5-6amps max. Measuring it is one way to be sure.
The max current in the common wire will be about the same since the coils are not on at the same time.
Any small voltage drop in the wire can be compensated with a small increase in the dwell setting.

Larger wire than needed will make it more difficult to connect to the connector(s) and result in a stiffer connection requiring improved strain relief. The best guide is to use the wire size used by the OEM.

As in many things, there are always several ways to look at this. Whether you use larger wire, or the smaller wire it will work, but with different trade-offs.
shaodome
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Post by shaodome »

Ion...

HomeDepot sells a 14-4 wire set in a grey sheeth of which you can buy by the foot. Thats enough for the ignitor and to run to the packs. Plus its all kept neatly together...check that out.
ion332
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Post by ion332 »

I got a set of nifty 18 guage shielded wire that is for heavy duty aviation apps (silicone insulation inside and out) I will use this for about 3 feet to get it out of the passenger bay, then after that I got your suggestion Jordan. :) Already had some of that on hand, its just hard to route through the dash and all.

I really just wanted to know so I can do as much as possible to shield the passenger area. Once its out through the front bulkhead, I am not so worried.
MSnS 029t
94 Probe GT custom headers/ short ram intake/282dur cams/modded intake
147wtq@6800/197whp@7700rpms
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