Ronald Kregoski Verifies K&N FIPK Power Claims Part 2

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Ronald Kregoski is an Organizational Psychologist by trade and a gear-head by heart. The Brighton, Michigan resident is also a freelance writer. “I read an ad from K&N Engineering concerning power gain on a 2000 Grand Cherokee,” said Ronald. “I tested K&N’s FIPK kit to see if it could meet the results from the ad, and I have to say K&N’s advertising was conservative.

You can read Ronald’s articles in his own words. Ronald Kregoski’s article also can be found in Cruisnews Magazine. Here is part two.

Putting A Little More Go In The Old Grocery Getter - Part 2 By Ronald Kregoski
Getting K&N just right at Wheel to Wheel
Getting K&N just right at Wheel to Wheel

Last month I reported my interest in checking out the claims that the K&N folks made on the addition of their Generation II Fuel Injection Performance Kit (FIPK) to the heavy breathing of a Jeep Grand Cherokee similar to mine. They claimed a whopping increase of 13.1 horsepower. This seemed high to me and while I was looking more at a mileage gain than horsepower, I wanted to see how close to the truth their claims were.

So, I replaced the plugs, changed the oil and developed a baseline for pre-FIPK mileage. Next, came the wrenching. Wheel To Wheel Powertrain, who was to do the dyno workup, offered to do that as well. How could I refuse?

At World to Wheels, Rich Gala and Dan Sienkiewicz rolled the Cherokee onto the chassis dyno. Now setting up for a dyno run is a little more than a stop and hop. After the Jeep was raised to the dyno table, Rich measured the wheelbase. Why? Because the Jeep runs in all-wheel drive and needs to be centered on four rollers. Then, comes chaining down the front and rear axles to keep the car from going ‘Christine’ on us; checked and rechecked. Next, a stand is placed in front to position two blowers for cooling the engine. At the backend, a tube is placed over the exhaust pipe and an exhaust blower is turned on. Finally, with a connection to the coil to pickup rpm and a control switch tossed into the car, she was ready to have her wheels spun for the pre- test.

After a few minutes, we had the results. Then a couple of more pulls to verify the numbers and one more to establish 1/4 mile performance. Now, Chrysler claims 235hp@4800rpm and 295 ft lbs@ 3200. Our results; 171 hp, at the rear wheel (that’s about 206 when you adjust for the power loss from an all wheel drive) and 225.4lbs of torque; and the 1/4 mile numbers of 16.6 at 78mph wasn’t going to establish any new records (see chart).

The dyno results are proof of K&N's performance
The dyno results are proof of K&N's performance
Next it was up to W2W’s Brian Walkuski, who worked through his lunch to do the wrenching. How often do you see that dedication? We laid out the parts on a table and checked them against the list of materials: an intake tube, the filter charger element, heat shield and a variety of brackets and clamps. The installation process is pretty straight forward; loosen a few clamps, remove the old air box and filter and bolt on the new stuff. Everything you need to do is on top and easily accessible accept for one bolt, which, on the Grand Cherokee needs to be accessed through the left fender well. The K&N kit also includes a great set of step-by-step, pictorial instructions for those of us who are better at deciphering pictures than words. These are the best and easiest to understand instructions I’ve come across for any bolt-on product.

Everything in place, next came the second set of runs. What I like about the W2W dyno is that it operates to SAE standards and will tell you the real potential of your vehicle to run a 1/4 mile. That is, the number you get is what your car is capable of running without having your staging, Christmas tree reaction time or poor shifting being a factor. This allows you to get an accurate reading of your performance upgrade as well as having a standard by which you can compare your beast with that of another located anywhere. The second set of runs with the FIPK installed produced 178hp; a 13.3 hp gain. Spot on no .2 better than the K&N promise!

But, there was one more thing, the engine’s computer needed to catch up to the new airflow the FIPK delivers. To do that, K&N recommends disconnecting the car battery’s negative terminal for a couple of hours to default the computer, then reconnect and drive the car for about 150 miles to allow the computer to readjust to the new air flow. It was another 6,000 miles and a couple of months before I could return to W2W but, the results were well worth the effort.

Back at W2W, Rich Gala went through his meticulous prep again and we were ready to rock and roll. In order to be accurate, Rich did 6 pulls and spent a couple of hours on the tests. He patiently allowed the car to sit and cool down between sets. Wow, what a difference. Not only did we get another 1.5 hp, (that represents a 9% increase in horsepower over stock) and 20.5 ft. lbs of torque but the FIPK took almost a half second off a 1/4 Mile time. And that’s with a 4500 lb car with 92,000 miles on its ticker all from a simple bolt-on! In addition, the 60 foot times improved along with both the hp and torque curve. There was a 19hp increase on the upper end between 4300-4900rpm where the better breathing really made a difference. Other cars can realize even greater improvement and I’m told that a FIPK can add 30hp to a stock Mustang.

After the upgrade I kept track of the Jeep’s mileage. The Grand Cherokee with the Power Tech 4.7 liter V8 is rated by Chrysler at 12-18mpg city and 16-22mpg hwy. I decided to only measure highway mileage as there are just too many variables affecting city driving to make for an honest comparative measure. Before the K&N upgrade, the Jeep’s on-board computer indicated that at a steady 65mph I was able to get 22.2 mpg. But with FIPK installed I was able to achieve 24.4. Wow, that’s a 10% increase in mileage. I’ve since learned that a 2+ mpg is what just about anyone can expect with the FIPK.

Recently I was towing my 24’ trailer with a car inside while a friend towed his car with his diesel truck. The truck got 9mpg while I achieved 10.3 at the same speed. In this day of rising gasoline prices, that’s meaningful. And remember K&N promises performance improvements other than just in mileage.

The first thing you will notice is much better throttle response along with a little more noise. The noise comes from the rush of unrestricted air and is probably why it is not included as an OEM component from the factory. However, it is music to any rodder and you may never want to listen to your car stereo again.

A severe test for the FIPK came some weeks later when I was entering US23 going north from North Territorial Road. There is a blind spot because of the overpass, which hides oncoming traffic. Last year my wife bent some rims and blew out two tires at that location when she turned our minivan into an off-road vehicle trying to avoid a non-yielding semi. As I moved down the ramp, my vision of the oncoming traffic was obscured. Finally it opened up and I could see a semi barring down on me! I mashed the loud pedal and without hesitation the Grand Cherokee leaped ahead with the ‘Whaaaaahh’ of a ‘60 Vette’s dual quads trying to suck in its hood. One look at the rapidly shrinking semi in my rear view mirror was enough to make me a believer of K&N FIPK’s real world performance.

I’m betting that with a little more tinkering with the engine’s computer and better breathing on the backside, you could coax even a few more ponies out of their stalls.

The K&N FIPK is a well-made product and goes together as advertised without any hassles or poor fits. So if your grocery-getter’s ‘get-up-and-go’ has got up and gone or you just want something keep a little more jingle in your pocket, a K&N Generation 2 FIPK might be a good place to begin. You can download the step-by-step detailed installation for your particular vehicle in by tapping into their website (

Also, if you need someone to build you a world class engine, super tune your go fast car or would like to see the real horsepower lurking in your street thumper as well as checking out what its potential for the 1/4 Mile would be, Wheel to Wheel Powertrain is the place to go. You can reach them at 248-589-1190. If you mention Cruis’news and this article they tell me they’ll shave $50 off their regular dyno charge.

Think a good thought and remember to put off puttin’ off!

Find K&N products for your vehicle using the K&N application search then use the K&N dealer search to find a K&N dealer in your area.

K&N Oil Filters

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K&N Engineering, Inc., with headquarters in Riverside, California, has been the world''s leader in performance filter technology since 1969, serving the needs of the automotive, motorcycle, marine, industrial and military markets. K&N is heavily involved in nearly every form of motorsports from off-road and powersports to drag racing, stock cars and road racing. For more information about K&N Filters, please contact K&N Engineering, Inc., P.O. Box 1329, Riverside, CA 92502-1329, (800) 213-4182 for a dealer near you, (800) 858-3333 for technical service/questions, (951) 826-4001 Fax, e-mail, or visit