"Performance" vs OEM coil

[JimRummy]

Had this AutoZone coil pack about a year now, and overall I am not pleased (see thread "Random cel flash" ). Just wanted some opinions. I've done a lot of reading about the accel, or screamin demon "performance" coil packs, and it seems like its a similar situation as with the cai , and e fans. Some are religiously loyal to OEM , while others have nothing but good things to say about cai's, and performance parts so I'm not sure. Anyway the OEM pack last 19 years/107k miles, so I know they're well made, but expensive. The screamin demon advertises nice numbers, but doesn't have the torture test results that the OEM's do. The one (possibly deciding factor) is that I have no interest in using any other plugs and wires then Motorcraft, so I didn't know if that would invalidate any benefits the demon packs may have. I also don't feel I should gap the plugs any farther, as I have had old over heating issues in the past, and am getting a quick cel, and I think misfire when going over large bumps.
Any input would be greatly appreciated.

 

[RonD]

Yes, OEM coil packs seem to last longer, wrecking yards are full of them , at a good price.
Just mentioning this because a used OEM coil can be better than a new non-OEM coil.

Manufacturers recommended spark plug gaps are not optimal, they are determined by middle of the road use on paper.
You will get better starting, performance and MPG by widening the gap by .001
You will get better high RPM performance by narrowing the gap .001

You can change the gap by +/- .005 to make engine run best for your use.
4.0l gap is .054, so .049 to .059

If you hit a bump and get a CEL then check the codes, if it is a misfire then you have a loose or shorted wire.
I would have the engine running with some one watching the CEL and then start moving wiring around, see if you can duplicate the quick CEL.

 

[JimRummy]

Thanks for the quick reply, that's what I was thinking, OEM usually had it right the first time.
Now, the last time I had a CEL (besides the MAF going out almost a year ago) was the coil pack dying causing a misfire CEL, and before that was the old wires were arcing causing it to buck. Seems like these coils and wires are not lasting like they should..

 

[JimRummy]

How hot does a coil pack get?