I am a new Jeeper and looking to replace my spark plugs. Ive been getting roughly 13 mpg and pretty low acceleration. I have 30" BFG all-terrains, and I understand bigger tires = less power.
What spark plugs do you seasoned veterans find provide increased perforance? I'm not looking for anything crazy, just some decent spark plugs.
Also, what else have you done to increase your mpg with bulky tires?

Extra Info: I drive a 1992 XJ w/ 4.0L I6. 138,000 miles.

 

The best plugs for our 4.0 is the Champion copper top plugs gaped at .035. Don't use bosch or any of those fancy plugs the only cause problem on our Jeeps.

 

I got a 01 xj with 125k and 31 trxus mts and ive used ngks in the past and they did good but i switched to e3s and i get about 16-17 mpg

 

You are correct. If I am not mistaken. Standard is Champion for 99 and older and NGK for 2000 and 2001 Both gaped at .035

 

I've used those champion copper tops in my Jeep and ran like crap with them and I run E 3 spark plugs now and not 1 problem with them yetbut and I got about 10,000 miles on them

 

Your right! I've just had some bad experience with champion plugs

 

Yeah I did try the Bosch platinum and they lasted for less then a week for me and that was maybe 25-30 miles only. My 98 ran so bad I went back to the champion and never had a problem with them. Some people have had good luck with the fancy plugs but I never did at least in any of my Jeeps.

 

I have champion. But my mpg sucks and I have like no power, I'm going to switch to e3s and try it.

 

Quote For Truth

Champion plugs come in the Jeeps from the factory.

 

What should I run in my 2000 4.0 champion copper plus or e3 plugs ? I keep hearing different opinions?

 

I got e3s in mine with no problems i had champions before and it ran like crap i use e3s in my cargo van that i drive 400 miles a day and they work great for me

 

Run NGK Coppers in yours. Don't run e3s

 

What were you getting before for MPG?

 

Around 14-15 mpg

 

I run e3s with no problems