The science behind CAIs

[blazinltz96]

Just curious as to what makes a Cold Air intake for these trucks work like they are supposed to and actually give performance gains. Looking at my factory intake and aftermarket high-flow K&N filter, i really don't see how just changing a tube essentially would allow the intake to suck more air. I could see an air box modification helping, just not sure what the science is behind the CAI's tubes/boxes that makes them work that much better than a factory intake. Any info is appreciated, been thinking about adding one just can't figure it out

[KingBird]

The cooler the air entering your engine, the denser it is. Dense air has more oxygen. More oxygen more power.

Theoretically, of course. Now when your intake piping is routed directly over your exhaust manifold, hot air rises and eventually will heat-soak the intake piping. The heat shield over your exhaust manifold does a good job of keeping that from happening, for a while.

This is why, when you watch a racing show, you'll see them icing down the intake before runs. Cold air = more oxygen, except for those of us at 3500' elevation. We're just screwed.

[Grimor]

Save your money, HAI don't really do much for our platform

[Trail X]

You're right Nick, its mostly a marketing racket. Some filters say that they allow lower air restriction, allowing less resistance to sucking the air into the cylinders (which is where a lot of parasitic losses come from in an IC engine). But the filters that are high flow generally also have worse particulate filtering... its a trade off. Honestly though, unless you run around at WOT and 5k rpms all the time, you won't see any power difference except for some increased noise.

[Berettaspeed]

I know this is an older topic, but I would like to add, I see many vehicles suffer from damaged mass air flow sensors with the oil soaked filters. That residue stains and coats the throttle body, mass air flow, and could effect idle sensors and many more.

Any intake that grabs air from under the hood is pointless. Make sure the air enters somewhere besides the hot engine bay. I cannot see much gained from high flow filters for off roading needs. Not to mention usually in dusty areas and these dont filter as well and just get clogged easier with that oily residue.

[HARDTRAILZ]

I would not go with any other filter than my high-flow oiled Green filter. The high-flow helps to keep enough air flowing when half the filter is packed with mud. The oil has literally kept water sitting on the filter rather than pulled through. Not sure why you feel it does not filter as well, but you might want to see my experience here...viewtopic.php?f=32&t=1392 Plus the cost saving of the Green over the multitude of typical filters I would have destroyed over the past 5 or so years is great. The filter cleans up and works as well as ever still.

[bartonmd]

Green is a bit different than the K&N and others like them, because they use cotton gauze cloth where the K&N and others like that use the much thinner cotton gauze. It was funny after ErikSS came out of a water hole at Badlands last month, because you could see the big-time steam/water coming out of his exhaust from where his lack of an airbox and spinning fan covered the filter in water and it sucked it right in. My filter is probably 5" lower to the ground than his (3" body lift + little bit of lift difference + tire size difference), and it (my stock paper filter) just got a couple splashes of water at the bottom of it, and the inside was clean.

[HARDTRAILZ]

Seems pretty silly not to have some kind of box protecting the filter offroad.

--Altough I do think Fish relocated his filter more ot the rear of the engine bay and that would give it some protection if you wanted open for HAI.

[bartonmd]

Seems pretty silly not to have some kind of box protecting the filter offroad.

--Altough I do think Fish relocated his filter more ot the rear of the engine bay and that would give it some protection if you wanted open for HAI.

Oh, I agree!

[Grimor]

I have nothing really boxing in my air filter, but I haven't had any issues so far. I have thought of adding an aquasock. It helps the filter on my SS in wet conditions.

[v7guy]

I'm a bit torn on the airbox, while on one hand the box does protect it a fair amount from a lot of mud and dirt, it also does pull air from down at the bottom which is lower down than just an exposed filter... depending on the scenario I could see one setup being just as bad as the other. I suppose a solution is to leave it stock and don't try to imitate a hippo. lol

There were a lot of issues years ago when the MAF started getting placed more inline between the airbox and throttle body, I seem to remember it really popping up around the time the LS1 Transams were released, I'm sure there were other models that it was an issue on too. But given how close the air filter was to the MAF if the filter was over oiled it was supper easy to completely FUBAR the MAF readings... light application of oil seemed to be fine.

Obviously our concerns are a fair bit different and this is an apple to avocados comparison. But I guess what I'm getting at is if you're going to use a K&N or the like don't oil the filter so it's dripping like a $2 hooker and it really shouldn't be a problem.

[HARDTRAILZ]

You can make or mod a box to pull air from the full front and all around element. Offering protection from water n dirt but keeping the air being pulled at same height. It also does some to prevent directly sucking hot air like an open element does.

[TBYODA]

Seems pretty silly not to have some kind of box protecting the filter offroad.

--Altough I do think Fish relocated his filter more ot the rear of the engine bay and that would give it some protection if you wanted open for HAI.

IMHO I don't think any variations of mods or the like what have stopped water for entering the motor when submerging the motor to that degree, other than a snorkel.

[HARDTRAILZ]

Seems pretty silly not to have some kind of box protecting the filter offroad.

--Altough I do think Fish relocated his filter more ot the rear of the engine bay and that would give it some protection if you wanted open for HAI.

IMHO I don't think any variations of mods or the like what have stopped water for entering the motor when submerging the motor to that degree, other than a snorkel.

Agreed. However, Mr. Barton was comparing the two trucks going through same water and the difference in that experience. Not the dunking that was done.

[v7guy]

Ah, we weren't talking about the dunking this whole time? Well, I mean everyone else wasn't talking about the dunking, just me? It actually kinda makes sense now sorta a lil maybe... where'd I put my stuffed unicorn? Stupid rainbows.

[KielTb]

What about cutting the hood for a ram air style intake? Should be high enough up on the passenger side of the hood however far back you decide to put it. Plus if it was wide and low profile it would look pretty clean and help avoid water unless you submerge the hood without a snorkel haha

[HARDTRAILZ]

Several us submerge the hood enough that would not be a good intake spot.

[v7guy]

Yeah, unfortunately it's not uncommon to get a good flood of water over the hood. Any kinda ram air type setup is no bueno if you're gonna use it off-road much.

[Grimor]

Yeah, unfortunately it's not uncommon to get a good flood of water over the hood. Any kinda ram air type setup is no bueno if you're gonna use it off-road much.

oh sure, now ya tell me

[Rickalicka18]

What about a cowl hood?