Cold air intake question... [Archive] - : Jeep Wrangler JK Forum

: Cold air intake question...

11-20-2008, 11:58 AM
I just purchased a 08 4dr rubi and I am considering getting a K&N cold air intake. Is it worth the $$. According to their sales pitch it should increase the hp a little but what does it do the the gas mileage?

11-20-2008, 12:30 PM
no, it is not worth the money. no cold air intake is.

11-20-2008, 12:38 PM
If everything else stayed the same it would give you slightly better gas milage due to a leaner AFR's. However, the ECU would compensate returning it to the same mixture as before. NOw if you had a way to tune for the new intake then you could lean it out.

To answer your question, there really is no noticeable increased power or MPG's from an intake unless you had a way to tune for it. People will argue both sides, but at the end of the day it is nothing noticable. People have al sorts of dyno charts showing increases and decreases of a couple horse power. FAct is you can get the same variances by simply doing a dyno pull every couple hours with no changes.

I would say the real benifit would be a filter that can be cleaned rather then replaced and many (not all) can filter better then stock. also they look cooler lol :laughing:

11-20-2008, 12:49 PM
save your money...just get a k&n replacement filter from your stock air filter.i have great..after a good day of wheeling i clean it out good as new...:D :D

11-20-2008, 01:35 PM
Most of the CAI's just make you more hydrolock prone from water splashes and so forth.

Save your $.


01-08-2009, 06:56 PM
I went back to stock intake box with K@N filter, looked like water was splashing in with AEM cone filter, bad design? liked the sound though:shaking:

01-08-2009, 07:44 PM
I went back to stock intake box with K@N filter, looked like water was splashing in with AEM cone filter, bad design? liked the sound though:shaking:

You should get a AEV snorkel. and you will have no prom with water..:smokin:.sell that AEM filter on e bay? on my name and ck out my pictures.:)

01-08-2009, 07:55 PM
i got roughly 1 millon extra horse power with my CAI and TBS lol j/k i love my intake but mainly for the sound and ability to clean the fliter but really no performance gians especially with the tbs but sounds way cool hahahahaha

01-10-2009, 11:18 PM
A higher flow rate air filter will result in less pumping losses which most often leads to increased power and mileage. But the benefit dependent on how much better the aftermarket filter is designed and whether or not the stock system is adequate.

While cruising down the road the RPMs and flow rate are relatively low so the difference usually isn't real apparent. As you get to higher flow rates, such as pulling power on a dyno, or if the systems flow rate is increased due to modifications (exhaust, supercharger...) then there is more of a benefit.

The amount of pressure (vacuum) between the filter and throttle could be monitored to compare air filter performance and signal when it needs to be replaced. If a gage is used it must be sensitive enough to read the slight difference from atmospheric pressure.

Side note - Many Diesel trucks including the Dodge Cummins has a device on the air filter box that will indicate the maximum vacuum in the box to indicate when the filter needs to be replaced. I have thought of adapting one to fit my Jeep but there may be too much of a difference in vacuum between the two systems.

Chris O.
01-11-2009, 11:56 AM
When my 08 Unlimited had less then 100 miles on it, I installed a Volant CAI. The intake noise @ full throttle was so obnoxious, that I could'nt carry on a conversation with a passenger. I put up with it for about 5K miles. It got to be so annoying that I went back to the stock intake system. Guess what? NO DIFFERENCE in performance or mileage.