Cold air intakes on overland rigs asking for trouble?

[Todd C]

I just ordered a cold air intake for my Gladiator and a buddy was telling me today that this is a huge no go. He went on by saying that from water to high dust kill these filters and should avoid them. I argued that the companies making these things specifically for offroad trucks would have thought of all that in their designs.

Care to add your opinion?

 

[smritte]

This is a hard one.
At work we have run several types on the dyno. I have personally tested diffrent types of air filters using oil sample analysis by sending out the oil to a lab.
What you have is actually two different questions.
1. Cold air intake
2. Air filter design

Lets start with air filter.
Most paper filters will filter very well. Off Road we get a ton of powder/silt. The micron rating is how well it filters. If you look at several independent air filter studies, you will see a chart by brand. Google it and look at several. You will notice a difference. The down side is the better the filter, the less it flows. I haven't looked in a few years but the Delco filter was the best for filtering. In my Cruiser, the filter size is big enough to not restrict at all. On my 04 TJ, Jeep made the filter size way too small and it restricted unless I ran a K&N. The problem with the K&N was it didn't filter very well. High flow but let a ton of dirt in. I saw this on my oil report. I ended up moding in a bigger housing and a restriction meter. The meter tells me how restricted the air flow is. Because Jeep didn't design the filter housing very well, The cold air intake I designed for it flowed better and actually picked up cold air instead of hot air by Jeeps design. I didn't notice a benefit but my engine was happy due to less restriction and better filtering.

Cold air intake.
The benefit here is also based on initial intake design. Most give no benefit at all and some can interfere with the airflow causing a hesitation in the mid range. If its all made of metal, the heat from the engine will heat the air causing power loss. How bad is it? Again it all depends on who made what. Most people will never notice any lose or gain but most are noisy. People tend to think the noise is power.

In the end, does a cold air intake hurt the engine? Hurt, no. Power loss maybe, power gain on a modern engine, less likely. Where do the companies get their data? Its easy to lie by omission. Just don't tell the whole truth. This is why you see "Up to 30hp gain". Key here being "UP TO". If your system is so bad your losing 30hp then any new intake will gain. Also most of the data is based on 1960's and 70's cars where the intake and exhaust was restricted from the factory.

Over all the damage is done by the filter. Look up filter reports. I will never run a K&N type filter in anything off road. It would take me way too long to describe the damage the fine powder will do over time. Over time meaning I want my engine to go over 100k miles. Do race people run them? yes, How long does a race engine last? Not 100k.
Don't advise people against them. People like them and you end up in an argument.
If you want something that will actually do something, snorkel and a good filter. Add in a restriction gauge so you know when the filter is dirty.