Well, the details from the old post are gone (circa 2007 @ SVS)...ultimately, the upgraded intake (cold intake) kits yielded no gains, but hurt HP on the top end. Nice noise, but nothing to gain. The stock airbox hands down was the best. We tested the 5.7's and 6.1's, and threw in a LS1 to the party, same results across the board. In terms of the K&N panel filter, the only good is that it is reusable (no gain in HP). That is the only reason why I use them to this day....(until I find an ITG).

Now about the ITG, it is the best panel filter I found using a stock box. I dyno my old '87 RX7 TurboII (circa 1990) @ Sanderson Headers. I use to AutoX and was always tying to improve the stock set up. Upgrades for the test; ROM tune, ported housing, seals, and upgraded turbo internals. Since I was in a "stock type" class, I had to keep it "looking" all stock. I tested paper, K&N, Apexi, ITG and a few other panel filters. At the end of the day, the panel ITG actually worked the best. Though the panel did not yield HIGH HP results, the ITG was the only one that gain a pony and a few lbs of torque. Nothing to scream and shout about, but any improvement will work. And guess what, it was the ONLY FOAM type filter.

Last one to add....

When I use to race bikes, Kyle Racing from Sand City, did all my engine and suspension preparations. Dan (Kyle) is the foremost private tuner of Honda motorcycle race engines (EVAR..lol). He always swore by the stock box and proved it. Once, I wanted to use the Dynojet kit,which came with a K&N panel. He advised me that K&N filters will do nothing to INCREASE performance. But, he did agree that long term maintenance for a daily driver...it is a cheaper choice.

Whatever I mentioned above is from my personal experience....that's all.

 

Here's a dyno, cold air intake shoot out using a wrangler as the test vehicle. Note the commentary on a larger intake tube flowing more air; all aftermarket kits provide more flow than the motor can use (restrictions elsewhere), and that only the later models of wrangler have an airflow sensor.

http://www.jpmagazine.com/techarticl...t/viewall.html

I also remember an article in MMFF that did the same type of tests with a 5.0 mustang and various intake kits. There was an appreciable difference in HP when the intake was lengthened and put near the front bumper, low and away from the engine bay. The intake picks up the colder air rather than the engine compartment air, and cold air is denser.

All of the above is testing on engines that don't monitor airflow and adjust timing/fuel accordingly, do it would seem to be a moot point with regards to the LRs.

Any published dyno results for our engines?

 

IMHO I'd be kinda scared to put my D1 on a dyno and see just how low it is... besides, ours are built for bouncing thru Borneo, not bleach burnouts at the track. Until you start down these paths..

 

Wheelgarage: Thanks for the info. It's always interesting to look at real numbers and rule out "placebo effect."

 

Care to share about how much of an improvement as well as - did you do any other major maintenance at the same time such as change the rest of your fluids and/or tuneup or other maintenance?

 

There's probably a reason K&N voids their air filter warranty if you use them off-road.

 

I looked at this sort of thing for the DOHC 24 valve six in my Mercedes, and the same sorta stuff, even from the chip people, long story short the dyno test that actually showed a 7 hp gain did not do so until 5500 rpm, and if you are on the interstate at that rpm, you are not worried about mpg, you are worried about the herd of blue lights behind you and the swiftness of the Motorolas they have....

But for some guys, knowing that have an extra 2 hp is worth it. Or knowing their truck is 1/16 of an inch taller than another. I'm just glad when mine has enough battery to crank, enough oil to make that damn light go out, and can make it down the road to the package store or the auto parts store (both on the same road, how handy is that?).

 

K&N air filters are pretty cool on Jap cars made for modifying but I wouldn't go for them on a LR, just doesn't fit.

 

K&N air filters can with time kill your MAF and it will allow more dirt into your crank case then any other filter on the market.

 

I won't run a K&N. Lets too much through, even on a road car. I use a dry element AEM filter on my car (made by K&N but very different from standard K&N filters). I agree with you on the CAI thing but I can tell you that in my car there is a noticeable difference in power with my CAI. The filter sits low and infront of the tranny and gets much cooler air that in the engine bay. Im sure that the JDM motor with higher flowing heads, intake manifold, along with headers, high flow cat, and full 2.5" exhaust also make the CAI more effective. That being said, I have spare cone filters laying around and wont waste my time putting it on the disco.