Discuss This Article
4 Wheel Drive HardwareI don't know anyone who wouldn't like a little more performance out of their vehicle. Whether it's a brand new Jeep TJ, a beat-to-death FJ-40, or a screamin' new Mustang, we all thirst for just a little more oomph out of our motors. Once we stick those giant tires on our rigs, we can almost watch the gas gauges move on their own and watch everyone else fly by on the road. And what about on the trails? When you need to get some horsies to the ground in a hurry to get over an obstacle, you want power and you want it now.

Of course there are dozens of ways to get better performance out of our rigs, including free-flowing exhaust, better gearing, throttle body modifications, headers, and many more. One company that's been helping racers perform better for years is K&N. K&N makes stock replacement air filters for many vehicles that directly replace your OEM filter. These filters add some power and do typically give some noticeable improvement.

But us four wheelers are a different breed. Everything we want has got to be better, bigger, bolder! When the Jeep TJ came out in '96 ('97 model year), I got one early on. By the end of '98, the Project TJ was beginning to be built up and with 32" tires was already feeling anaemic. At the time, K&N was not yet making a direct replacement filter for TJ's and the one for YJ's, though similar, did not fit in the TJ's air box without trimming.

K&N Home Mod.
Our own K&N modification.

After talking to my fellow TJ'ers I decided to do my own modification to fit a cylindrical air filter on the cut-down stock air tube of the 4.0L motor. In January of 1999, we ran a brief story telling how exactly to do this modification on the 4.0L and also the 2.5L Jeep motors. This mod. has proven very popular among the TJ ranks and we get a ton of people asking about this setup every month. One thing to keep in mind with this setup is that it can void the warranty on some motor parts and may not be legal in your state.

Last November at the SEMA Show in Las Vegas, K&N rather quietly introduced their new Fuel Injection Performance Kit or "FIPK" for the Jeep TJ six cylinder motors. I was very curious and excited and had one sent out for us to try out on our Project TJ as soon as they were available.

So what's the scoop on the FIPK? In the case of the TJ, it is considered a Generation II kit, which means that it consists of not only the air filter, but also a new air tube (intake tract), heat shield (baffle), and everything else you need to get going.

The K&N FIPK for the TJ is claimed to increase airflow to the throttle body by up to 26%. K&N also states that the FIPK kit is 50 state emissions legal and is also CARB (California Air Resources Board) approved and the kit will not void your vehicle's warranty. K&N backs the kits with a 10 year, million mile limited warranty, as well.

The FIPK straightens air-flow and also increases the amount of air being pulled into the throttle body.

OK, so there are all the claims, but how's the FIPK really work? Here's the scoop. To quote K&N,

"...the K&N Fuel Injection Performance Kit (FIPK) dramatically reduces intake restriction as it smoothes and straightens air flow. This allows your vehicle's engine to inhale a larger volume of air than the OEM air filter assembly. More air means more usable power and torque throughout the engine's RPM range, with even greater power gains in turbocharged and supercharged engines. "

So there you have it. Straighter line of air-flow, less restriction, and more volume of air give you more of that oomph we were looking for earlier.

I've been running the FIPK (part # 57-1514) in our Project TJ now for a few months. One of the hardest things for me to do before writing this article was to determine if this thing really works and if it does work, how much better does it work than my own, previous, mod.? This has been a difficult task without having access to a dyno or other testing equipment. So right here and now I will make my statement and disclaimer, if you will:

All comments as to the performance of this K&N FIPK kit are made solely on my seat-of-pants feelings and I offer no scientific proof, whatsoever!

What I will say, though, is I have a fairly good seat-of-pants to make my claims by and have full confidence in my seat-of-pants!

Now before I make my statements, let's take a look at the FIPK and how it all installs. You will need a minimum of tools and about an hour or less to do the installation.

READ ON! ---->>>>

Main page | Installation | Conclusion



Help spread the ROCKCRAWLER world!           Share on Facebook

©1997-2015 ROCKCRAWLER 4x4 and Off-Road Magazine. All Rights Reserved.

RockCrawler.com   -   IH8MUD.com