Ignition coils, wires and such

[holeski]

I was wondering what everyone was using for Ignition components on everything from stock to mild built to there strokers. From what I have read Mopar recommends there performance coil which is made by Accel. But I have seen a lot of discussion for the Accel coils crapping out within the first two years of use. It also seems that Jacob's Electronics was bought out by Accel. MSD doesn't have very much in way of Jeep products and I haven't read much about what they do have except you need to but a plug adapter to make it work.

Plug wire diameter, whats better bigger or smaller?
All Napa ones are 7mm, Mopar recommends 7.5-8mm, but I have also seen 8.5mm wires for the 4.0L out there.

Plugs and plug gaps, what gap are you guys running? stock is what .035. I gaped out my YJ to .045 just to see and it seems smother but not more powerful.

So I guess the main question is cheep ol Napa stuff good enough or is there a better choice? coils, Accel or MSD?

[IH 392]

I run the NAPA/Echlin cap and rotor, Jacobs spiral core wires (I got them for FREE) Accell coil, specific application for the Jeep 4.0, been on there for 13 years now and NEVER! misses a beat, Autolite plugs with the center electrode bent over to make it a "short" side electrode, don't know if it's beneficial in the Jeep, but it made a world of difference in my racing kart! I don't notice any difference between a .035" and .045" gap?

I had a Jacobs "Mileage Master" system on there for a while, it was of absolutely NO benefit on the computer controlled engine! ('97) the guy I got it from said it worked good on his jeep???, I got my money back out of it so it was no big loss.


I believe in a HOT! ignition system for every engine, you can have all the goodies but if you can't light the fire they do you no good!

[ajmorell]

I'm running a MSD Blaster coil, Taylor wires, Accel cap & right now the standard champion copper core plugs. I have Autolite platinums to switch to just havent' done it yet.

[amcinstaller]

i was wondering this too. in my engine though i will be running a megasquirt, and another popular choice (not heard much in a 4.0, but 4.2 all the time) is to swap to an HEI. any advantage in that in a 4.0, or just stick to 4.0 style coils?

[Don H Jr]

MSD has a good upgrade coil for 4.0s as well as super wire set too with looms parts to organize same. They also have the big multispark boxs that hook up along with a timing dial for your dashboard and double set rev limiters and more. What they don't have is a billet or any distributor for the HO 4.0. No one does. By the way MSD Wires are 8.5mm.

Don Jr

[Don H Jr]

I made wrong choice, I think, gettting upgraded coil this month. Got Accel, which said on the box in fine print, "Made in China."

Don Jr

PS: I wish I'd a got the red one instead, MSD.

[shawnxj]

accel has a distributor for the 4.0

[Don H Jr]

Yes Shawn they do have one for 4.0 but it's for Renix with vac advance on the side only.

don jr

[shawnxj]

really? hmm wasn't aware of that

[laxplayermjd]

my renix has no vac advance on the distributer??

[Don H Jr]

Lax: Can we talk Bimmers off line?

Don Jr
323ic Hers. I so miss my black/black 87 325is. What a bang for the buck.
and a bunch of old 5 series under trees that served me well over the years till pooped out beyond my limited abilities to diagnose and fix em.

[4.whoa]

I'm running MSD superconductor 8.5mm wires. Universal kit so I could size/ route them my own way. Splitfire plugs- original, not tipped. I gapped them so
the split end spans .035-.040. Say what you will about them, but I noticed a big diference over previous champion golds