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Upgraded tune up time

ShoeterMcgav

NAXJA Forum User
NAXJA Member
Location
Colorado
I searched and searched and I think I put together a pretty choice set up for a quick "tune up", at least as far as spark is concerned. Plugs seem to be highly debated, a lot of folks favor Champion truck plugs and/ or NGK., autolights a runner up. Gimmicky plugs such as bosh iridium etc etc our vehicles tend to hate- exception to every rule of course but why spend more?

The main thing I wanted to document is the wires, cap,and rotor I finally found. Previous build my ZJ was plenty happy and jumped to life as soon as the ignition was bumped, with Livewires and MSD products. Not wanting to spend hundreds of dollars on wires and an MSD ignition I kept searching. Read forum posts and found a lot of people happy with Mopar performance wires pretty favorable and an upgrade over stock at 8mm. Those are harder to find as moparperformance.com doesn't even list our rigs anymore. Further research and I read that those wires are made by Taylor. Which lead me to the 8.2 Thundervolt vehicle specific performance ignition wire set. Features only 40ohms of resistance, Ferrite spiral-wound coated core of copper/ nickel alloy, and heat resistant up to 600* sleeves.
Part number is 84249, found for 41 bucks on Amazon.

Pretty happy woth that score, as most other 8mm+ wires were closer to $100 or more. Next up is cap and rotor. These aren't usually expensive, but a ton of em are CHEAP. Main thing here is wanting brass terminals for best conductivity. I looked at waaaaaay to many cap and rotor combos, and was surprised to find how hard it was to find both in brass. Most of the caps that feature brass contacts come with rotors that I could clearly see polished silver looking contacts.

SUM-G5230 - Summit Racing® Distributor Cap and Rotor Kits

From summit. Price was decent, made in the US is a bonus, and delivery wasnt too far out.

All in all I got the whole tune up kit for right around the $75 Accel "truck tuneup kit" offered on Amazon and other places. I think this has superior wires, plugs, and the rotor I think is better too.

Hope this helps someone, or at the very least will be a reference point for myself down the line.

 
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Cap and rotor
https://www.summitracing.com/parts/sum-g5230

Wires
https://www.amazon.com/Taylor-Cable...ords=Taylor+Cable+84249&qid=1623720950&sr=8-3

Spark plugs: Champion, NGK, or Autolights all seem to get good reviews with the 4.0. Dealership gives you NGK plugs in mopar boxes as they became OEM at some point so thats what I went with from autozone. Oddly they list 2 offerings of NGK one over 5 bucks. Ironically the "cheaper" ones around 3 bucks I think? Looked to be the same part number- I didn't say anything of course lol
 
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Thats a good call... It has been operating just fine, but I might swap it on principle while replacing everything else.

Seems like most opinions I read about 4.0 ignition is to keep coil oem and stay away from MSD or equivalent. Any thoughts on that?
 
I did the whole screamin demon kit, coil, 8.8 wires, new plugs, high end cap and rotor; waste of money on mine. No difference in performance or gas mileage wise. But my motor is shot and burns a crap ton of oil so your mileage may vary.
 
I used napa echlin cap rotor with brass terminal's napa belden plug wires.
 
Ive had good results with Napas line back in the day... for some reason finding the upgraded wires and an all brass cap AND rotor proved difficult this go around. All I could find was stock 7mm wires from napa this go round. They also were the same price or close to the Taylor 8.2mm wires :shrug:
 
I put on a Kolak ignition kit back in the day (anyone remember those?). He was a guy on Jeep Forum who sold kits of quality components. The kits consisted of:

Magnecor KV85 wires
MSD high output coil
Heavy duty brass distributor cap and rotor (USA made)
Autolite platinum plugs

I've since swapped the plugs out, but they looked great after ~50k miles and had maintained their gap reasonably well. I think I gapped them at .045-.050 when I installed them. Probably not the best money spent as I did not need to replace the coil and a larger spark gap on a 4.0 doesn't really gain much, but I feel good knowing they're quality components in there. I'd do it again.
 
I remember Kolak for sure! I think he pieced together livewires and msd with autolights for me too...
Definitely got my Doug Thorley headers for the v8 ZJ from him. Awesome guy to work with, and top notch products to be sure.

I'm on the fence about changing my coil tbh. Same as you were, it's working fine atm. Idk that its worth it, but I know that piece of mind knowing when it was replaced is worth some sanity points to be sure.

Stock gap is .035 right? The extra gap (with supported extra spark from coil) might net some mpg gains (minimal at best), every bit counts when rolling on 35s though
 
That's the interesting but good part! When I installed a MSD on my 2k it provided no benefit above 3000rpm but I gained 10hp on the bottom end where I need and use the power band the most! I still want to try some E3 plugs but since they have a set gap?
 
2000? Don't those take coil packs instead of just a single coil? Good to hear you netted some actual gains... over 600 bucks on coils is ruuuuuffff
 
They only take a single coil, it just has 6 outputs!!!
P1080691_zpsyx1g0okt.jpg
 
Ah, ok! My, hell what was it, WK? Grand cherokee hemi 2009 or something, had a coil pack per spark plug. Not cheap either... The spark plugs were also unnecessarily a pita to get to if I recall. Not my favorite jeep to be sure lol
 
I originally looked into going "coil on plug" but the electrics wouldn't allow that!
 
I originally looked into going "coil on plug" but the electrics wouldn't allow that!

I'm still looking into this. I found info on various sites. I think on some board for Vipers, a guy was running some on an earlier model. The main issue is if the ECM can take a voltage surge.
I do have the KOLAK upgrade. I was running Champion Truck plugs. I think the NGK are a better option. I think I've ordered stuff from KOLAK in the past 2-3 years.

I'd also add to upgrade the battery wires.
 
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