CAI & FMIC

[FATAZZ]

hey this has been bugging me lately, if u have a intercooler, y do u need cold air induction?

[JCMarshall_Law]

No, but your car may spontaneously combust

[pinoi_boi_r33]

the cooler can only take out so much heat energy from the charged air. the colder the air is to start with the better.

[FATAZZ]

can u explain how it will combust? the intercooler cools it down

[FATAZZ]

so aslong as my outlet pipe on my cooler is cold, but if it gets hot its not doing its job right?

[pinoi_boi_r33]

no. it gets hot from the heat soak. ie from the engine heat. Yes this will heat up the air inside it. But very very minimally, since the air inside the piping is moving very fast, the heat from the pipes would not have enough time to heat the air inside.

basically the colder the air the better. as colder air is denser ie. same volume but more oxygen. more oxygen the better for the combustion process.

[xRHETTx]

Ok, if the intake air with CAI is say 30 degrees, the turbo heats it to 60 degrees, the intercooler might cool it by 15 degrees say, ending with 45 degree air going into engine.

If no CAI, the intake air may be 55 degrees, the turbo heats it to 85 degrees, the intercooler might cool it by 15 degrees, ending with inlet temp of 70 degrees.

It wont combust

[riceline]

the cooler the air to start with the better.

The Intercooler can only take so much heat out of the air. So by giving it cooler air to start with you make its job easier. There for it can cool the air that little bit more again over what it would be if you didn't have the CAI.

Think of it this way.

Hot air in > Intercooler cools it down but a section of the intercooler heats up.

More hot air in > Intercooler cools it down. Bit more of the intercooler heats up. Less cool area for the airflow to go over to bring down the temp air temps.

MORE hot air in > Cooler has been working so hard to bring down the temps for so long its now a heatsink.

If you start with colder air you prolong this from happening for as long as possible.

If you have a really good CAI it may never happen to you.

[FATAZZ]

cheers heaps fellas, ima go ahead with a few little CAI mods now:)

[JCMarshall_Law]

if u have a intercooler, y do u need cold air induction?

The answer to your question is no, but CAI may help reduce inlet temps.

The car spontaneously combusting was a joke,

and

Ok, if the intake air with CAI is say 30 degrees, the turbo heats it to 60 degrees, the intercooler might cool it by 15 degrees say, ending with 45 degree air going into engine.

If no CAI, the intake air may be 55 degrees, the turbo heats it to 85 degrees, the intercooler might cool it by 15 degrees, ending with inlet temp of 70 degrees.

It does not work like this, heat transfer is not a linear relationship. If you increase the turbo inlet temp by 15 degrees, the engine inlet temps (after the cooler) will not increase by 15 degrees. The higher the temp the faster the heat transfer, it is basic heat transfer theory.

[xRHETTx]

The answer to your question is no, but CAI may help reduce inlet temps.  

The car spontaneously combusting was a joke,  

and  

It does not work like this, heat transfer is not a linear relationship. If you increase the turbo inlet temp by 15 degrees, the engine inlet temps (after the cooler) will not increase by 15 degrees. The higher the temp the faster the heat transfer, it is basic heat transfer theory.

Yeah i know this but i was just trying to keep it simple to understand.

Maybe i should have just said CAI=good, No CAI=bad.

[HYPERTUNE]

The answer to your question is no, but CAI may help reduce inlet temps.  

The car spontaneously combusting was a joke,  

and  

It does not work like this, heat transfer is not a linear relationship. If you increase the turbo inlet temp by 15 degrees, the engine inlet temps (after the cooler) will not increase by 15 degrees. The higher the temp the faster the heat transfer, it is basic heat transfer theory.

I was going to say the same thing. Guess I don't have to now.