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Cold air intakes & turbos?

1469 Views 9 Replies 6 Participants Last post by  MagicMT
Just wondering why are CAI's so uncommon on turbo cars? I know there's a CAI for the New Age WRX, but it just doesn't seem very common on turbo cars from what I've seen. I thought about it some more and guess that it's because the IC would be cooling the air... But wouldn't it still be better to start out with cooler air?
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i think it has to do with the fact that you will be shoving colder air into a metal chamber (turbo) that on the other side of it has 1500+ degree exhaust gas flowing through it. also, i guess people just assume the IC will handle all cooling needs.
You'd probably have to have some custom tubing made to get the intake in the wheelwell, or you could build a custom design yourself. Most people probably just don't care enough to get the few extra ponies.

I don't see it helping very much anyways... the air will be cooled by time it's used.
It is all about money. To provide a cold air intake would up the cost of the kit substantially.
scoobyrs25 said:
It is all about money. To provide a cold air intake would up the cost of the kit substantially.
how much does it cost to make a tube that extends an extra 10" or so (atleast on a subaru)?
It is not a straight tube. A true cold air intake has bends, and they are expensive.
Some people do use a CAI for thier turbo, or the factory box which is essentially a CAI. Here's the way I see it.

Lets say your intercooler is 80% efficient.

Your hot air intake sucks in the air and after compressing, it's 150F. That makes the air about 120F at the TB.

Now you get a CAI so the air is now 100F after the compressor. (in this example the other intake is in a hot area of the motor). So with the same intercooler efficiency, you are now at 80F at the throttle body.

Given the standard 1% hp increase for every 10F you lower the intake temp, that's a 7% increase in power.

93 1.8T
(currently running a hot air intake)
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Yup, cold air intake is the way to go. It just costs more.
If people have enough $$$ for a turbo, then you'd think they'd spend a little more for a CAI... :confused:
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