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Better spark plug

Better Plugs for a 4.0L

  • NGK

    Votes: 34 20.0%

  • Champion

    Votes: 97 57.1%

  • Bosch Anything

    Votes: 23 13.5%

  • Any Basic Plug.. Acdelco Autolite

    Votes: 16 9.4%
  • Total voters
    170
O

OverTheHillsATTW

NAXJA Forum User
Location
Pennsylvania
Basic question which plugs are better in a 4.0? Personal opinion? I am about to do an all around tune up and will poll some ideas while im outside.
 
What about pulsar? I would never buy them cause there about 25$ a plug, but they look cool. there supposed to give more power and better mpg. the epa claims that there is a ~2% increase in mpg with them.
 
would it depend on what year you have? renix, odb1, or obdII?

for my 89 ive had good luck with plain old copper champion and autolites.
 
have been told by a number of mechanics in stealerships the best plug is normally the stock plug. Depending on the year you use anything else and it you are taking the risk of it running like crap. Know a number of people spend money on fancy performance plug to get no performance difference and decreat MPG.
 
Best spark plug, is more a matter of personal preference then anything else in most cases.

For me Champion Copper Plus has worked best for me in my JEEPs, 96 XJ, 93 ZJ and 95ZJ all 4.0. I have tried more expesive plugs with no noticable difference. My motorcycle Honda VT1100, on the other hand, eats cheap plugs. It will barely start, if I try to run Champion CP and burn the plugs up in 1000 miles. It does best on NGK or Bosch, platinum plugs or better.
 
If it sparks it runs. They don't need a vortex, or a flame cone, or any other crap. I know Jeeper's like Champions, but I had a couple of shitty running vehicles (old V8's)as well as 2 stroke motors foul them out pretty quickly. NGK's hold up better in those conditions.
 
Bosch platinums have failed me in my first tune up. (Pre-Naxja) Have used Champions since in both my 96 and 94. I replace them every year even though I only put about 6-7000 miles a year on either.
 
Wow! Every vehicle I've had since '93 has went 100K miles on the original plugs. Some were Autolites or Motorcraft. You're going to wear out the spark plug holes. The failure mode should be the gap geting way to big.
 
Champions for standard dizzy with wires setup and NGK for COP system.
 
Jeepm@n said:
Bosch platinums have failed me in my first tune up. (Pre-Naxja) Have used Champions since in both my 96 and 94. I replace them every year even though I only put about 6-7000 miles a year on either.
Click to expand...

Wow :wow: 7,000 miles per year? I do that per month when I am in the US.

And oh by-the-way, I am using the recomended Champion spark plugs 135,000 miles and counting, averaging 21 MPG.
 
Part of the problem with running other brand plugs is the heat ranges. When the other manufacturer doesn't have an exact match on the heat range, they cross you to a colder plug as that's safer than running too hot of a plug. Particulary with the botique plugs like 4+, u-shaped oddities that they only make a few different heat ranges.

A slightly colder plug usually isn not a problem, but it can lead to fouling. As an experiment, try crossing the champion plug to a bosch, cross that bosch to an autolite, to a whatever, to something else, and then back to a champion. Odds are you'll end up with a colder champion plug than you started with.
 
techno1154 said:
Wow :wow: 7,000 miles per year? I do that per month when I am in the US.

And oh by-the-way, I am using the recomended Champion spark plugs 135,000 miles and counting, averaging 21 MPG.
Click to expand...

I have a company vehicle I drive home. I average 5-7000 miles a month on it. My Jeeps can sit up 3 weeks before being started or run to town. I love getting in them after driving my work van all day. The Jeeps really have some low end zip.
 
NGK V-power copper....
 
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