Performance gains would be marginal at best with the addition of the K&N alone. Don't expect more than 2-3 RWHP (if that) at the most. However, it is a worthwhile upgrade IMHO. I prefer the drop-in (unitl K&N comes out w/FIPK for the ZJ 4.0). You may also want to try the Turbo City or Rusty's Off- Road intake setup. I used some of the ideas at web page to modify my stock airbox.
1994 ZJ 4.0, RE 3.5 lift, 32x11.5 BFG MT's on TJ Canyons, Bilsteins w/front JKS conversion, Borla header, Car-Sound cat w/Turbo City exhaust, Powertrax No-slip (rear), K&N drop in w/modified factory airbox.
True the gains might not be that much but they are gains. There are a few tubes that can be fitted onto the K&N cone such as Rusty's or Turbo City. They claim at least 5hp gain. Either way it sounds a whole lot nicer than the stock intake.
More Air = More Power
The K&N air filters are some of the best you can get from your local parts store. The K&N filter uses cotton instead of paper to filter the air. The cotton filter will let more air pass through faster. The best thing is when the filter gets dirty, you can just take it out and clean it.
Last edited by BackRoad4X4; 10-26-2013 at 01:51 AM..
More air in the engine = more exhaust gasses that needs somewhere to go away fast, and the stock exhaust is not really great at that.
I would think that if you upgrade your exhaustsytmen to something that is less restrictive than stock, you gain more hp than you do from a K&N airfilter.
More Air = More Power
The K&N air filters are some of the best you can get from your local parts store. The K&N filter uses cotton instead of paper to filter the air. The cotton filter will let more air pass through faster and collects more particles in the air. The best thing is when the filter gets dirty, you can just take it out and clean it.
Congratulations on resurrecting the oldest thread I've ever seen....12 years old! Lmao
the bottom line is ; what kind of driving are you doing, what intake & exhaust upgrades have you done, the age of the vehicle, etc.
it is easy to presume a benefit, thats why this exercise they provided is so valuable, it is just plain science fact, no opinions.
dont be mislead by the hype of how much more power you supposedly gain,
This x2. In trail dust and mud, I think that 5hp gain isn't worth it.
95 Laredo 4.0, 2" RE BB, RC N2.0 Shocks, Custom Roof-Mount Light Bar w/ 6 lights, Bumpers deleted, Homemade sway bar discos, Michelin LTX 31x10.50s, and a Dog Box :)
Planned: Homemade Spare tire carrier, double shear front track bar, 4 adjustable rear control arms, New Rims and 33" Wrangler MT/Rs or BFG M/T KO's w/ LOTS of trimming.