[Shane]

Just got a K&N FIPK (overpriced and thinking I should have stayed stock) and was wondering if anybody has installed one. My specific question is about the "seal" around the "heat shield". I doubt it keeps out any heat, it's more like a splash shield. Anyhoo, this "seal" does'nt look like it seals anything and I was wondering if anybody actually put it on or just chunked it like I think I will. PLUGS What brand and type of plug seems to work best in the 4.0? I've tried Splitfires and Bosch +4's and was disappointed. Good ol' Autolites have never failed me, so are these more pricier plugs worth it? Oh, and is the plastic shield over the plugs just for looks or does it actually do something?

Thanks for the help,
Shane

[Jerry Bransford]

Splitfires are cheaply made snake-oil gimmick plugs, I'm surprised you hadn't seen that mentioned in the 1000's of threads over the years where I've yet to see anyone actually recommend them after using them.

Bosch +4 plugs are also a gimmick plug, though higher quality than Splitfire. But they don't do well in Jeeps, it seems everyone that tried them said their Jeep didn't run well on them.

Believe it or not, it's hard to beat the plugs the factory recommends and uses. There is no magic spark plug that will add power, HP, or increase fuel economy over a conventional plug.

The only aftermarket type of plug that does have an advantage are platinum-tipped plugs... but they don't perform any better, they just outlast non-platinum tipped plugs by 2X to 3X.

But you even have to be careful with those and know whether your engine needs single or double-tipped platinum plugs. Distributorless (the latest) Jeep engines can only use double-tipped platinum plugs or plugs without platinum at all, they cannot use single-tipped platinum plugs.

Older Jeeps can run single or double-tipped platinum plugs but there is no benefit to double-tipped (platinum on both sides of the gap) plugs with a conventional (with distributor) igntion systems.

The FIPK is a waste of money on a TJ IMHO. While they can add performance to some vehicles, they don't help Jeep engines because TJ's air intake systems are not restrictive like many others are.

[TurfJeep]

thanks for the insight into FIPK's. i was looking at getting one for my cherokee and wrangler. now i can save my money for something else. thanks for the help and all the info on the forum.