Honestly, a stock engine doesn't need anything more than what it came with. That said, I do have a K&N filter in my truck and one other car. Neither made a difference in mpg. Throttle response always seemed crisper. But there were no appreciable gains other than the SOP-factor. I have kept track of the truck expenses, and paper v. oiled element have run neck/neck.
if you have a stock engine, then it is definitly not worth the money, little to non performance gains. Once you get headers, MSD ignition system, and maybe some trottel work (spacers) then you can definitly see some great results from your engine.
Only reason I say this is because I have had the FIPK from K&N in the past and haven't seen much performance gains until I did some more engine work. Hope this helps.
Also check out Jeepsunlimited.com, all the forums.
Thanks for the comments I appreciate them. I ordered the AirRaid ez install intake system today and I couldn't help but throw in the airraid throttle body spacer as well. I should get within the next few days and I'll let you all know if I notice any differences. Thank again.
I put in the new Airraid Quick fit system and it sounds great. I don't know how I'm suppose to see any increase in fuel economy, seeing how I can't seem to keep my foot of the peddle. I love the new sound.