Stock or Aftermarket Tune-up parts?

[jmsull]

I've searched, and like everything else, it seems like it's all a matter of opinion, so I want yours.

I have a '99 4.0L, aftermarket intake and exahust. Mostly city driving, some highway, and way too little offroad. I plan on taking a trip cross country this fall so I'm trying to get the Jeep ready to go. I'm at the point where I am going to do a tune-up. I just got it a few months ago with 79000 on it. I don't know when the last time the plugs, cap, rotor, wires and coil were replaced, so I figure I'll do it now so I know.

My question is: Stock or Aftermarket. Again I'm going to replace the cap, rotor, wires, plugs and coil.

From what I read, I want brass terminals on the cap and rotor. 8.5mm wires seem to offer a little more performance, but do I need a better coil than stock to reep the benifits. If so which one? I've read the Accel coils seem to fail a lot, maybe MSD. I looked at their site, they says the 8228 only works up to '97, anyone using this on a '98 or newer? And what about plugs? Mopar(Champion I belive), Autolite, Bosch or something else? What about gapping, any suggestions?

I'm tempted to just go stock all around. I know it will all work. But I'm open to trying other stuff if it will be reliable and justify the extra cost through increased milage and/or performance.

 

[5-90]

The OEM ignition electronics are fine, unless you're going to go with a big stroker or forced induction.

I usually use Borg-Warner caps - due to brass terminals (the silvery-looking terminals on most other caps are aluminum - and are highly susceptible to HV erosion. Why are they used? They're cheaper.) The Borg rotors also have brass contact tips.

There's a lot of debate out there on plugs, so I'll crystallise what I can from memory -
Splitfires aren't worth the money, so don't bother.
OEM Champion plugs are OK (to most - I don't like them.)
Going with platinum plugs is/isn't worth the money (they're all I use - conductivity and longevity are the issues for me. I use Autolite Platinum.)

You can probably run nearly anything you like - the reason I don't like Champions is that I had a set literally explode in my old Bug - and I tend to remember things like that. I like explosions - but not under the hood. However, they must have fixed their issues, because there are a lot of people here who swear by Champs. I just happen to prefer Autolite (I know they're made by the same people who bring us the Fram filters I flatly refuse to use, but the plugs are workable.)

For wires, pretty much anything will do. I happen to have a crimper, so I just buy a bulk roll of MSD 8m/m wire and make my own. Borg-Warner makes good wires for the money, and Bosch is spendy. Autolite is usually a "take it or leave it" deal for me on wires. If it's my money being spent, and I have to get a set that are already made up, I'll take Borg-Warner or Niehoff (same outfit.)

The coil on later vehicles does not typically need replacing at intervals - I've got a RENIX coil in my 88 that came from the factory, and now has 17 years and almost 245kmiles on it. I'd suggest MSD for a replacement, but I don't suggest replacing it unless you are having problems. The coil, as I recall, is the same from 1991 to 1998 (all ChryCo coils, and they went to COP in 1999.)

Keep your plug gap stock - if you aren't changing the engine, there's no reason to change the gap.

Take the money you would have spent on the coil and spend it on a filter and fluid change instead - and it will be money well spent.

5-90