Air box question

[rex adams]

I recently purchased a 2006 Lj and during servicing, found the air box cracked in 2 different places. One place was where the top attaches thus allowing the filter to displace and unfiltered air into the intake. I epoxied it back together for the short term. Do you recommend staying with oem replacement box or one of the aftermarket "cold air" style filters?

 

[Chris]

I recently purchased a 2006 Lj and during servicing, found the air box cracked in 2 different places. One place was where the top attaches thus allowing the filter to displace and unfiltered air into the intake. I epoxied it back together for the short term. Do you recommend staying with oem replacement box or one of the aftermarket "cold air" style filters?

Yes, please do stay with the stock airbox. Read this thread: Cold Air Intake FAQ

There is little to nothing at all to be gained from a cold air intake on these engines. Even one of the engineers who designed the Jeep Wrangler TJ said this:

"As with any "system" on the vehicle, such as the air induction system, there is a certain amount of compromise that needs to be designed into it. What I mean is that you could maximize flow, but at what cost to filtration and protection of the engine? Essentially we design the stock intake system to meet the airflow requirements of the engine while still protecting it from fine particle ingestion. Will a cold air intake possibly flow a little more? Perhaps, but it may potentially allow larger particles through that the stock paper element would not.

In the case of the TJ, the 4.0L is an engine optimized for low RPM power and torque - the potential increase in airflow that a cold air intake might offer would not really play into the typical RPM range that a 4.0L generally operates in."
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So really and realistically, you have nothing to gain from a cold air intake unless you're getting it for free. Not to mention that most of the air filters (i.e. K&N) that come with cold air intakes can actually do more harm than good for your engine, due to the fact that a lot of particles bypass those filters.

 

[Jerry Bransford]

Stick with the OE air intake which easily flows more air than the engine can consume at WOT and redline rpms.