yeah if you don't know what you want it seems they don't wanna give it to you, but they do have SOOO many jspec goodies, how can you complain (ok price is a bit steep)!?

is it entirely true that colder air in means colder air out across the turbo? doesn't it all get heated to one temp? how can it be heated to less? it goes through the system, the available heat is constantly replenished, it can't go beyond the threshold of heat but how can it be below it? i mean ok... so the graph isn't linear, so it must look logrithmic or exponential right? i think logrithmic, ambient plus or minus a few under the hoods isn't gonna land you anywhere lower on a log graph but that's just my personal speculation. if you suck more air in initially because it's colder it may justify cai use but still... ambient plus a few under the hood degrees... i don't see the big deal.

 

gh

 

i think your getting to hucked up on the reduction of themp that the air box will give you. the major performance advantage will be due to the grater consetration of O2 not it temp after the turbo!

in the ideal situation you would be able to have a positive presure in the air box (loads of dukting from the front end) or at least a reduced negative presure! this would mean that the turbo is not having to work as hard to get the air in and thus give you quicker spool up, etc, etc.

thanks Chris.

 

That apexi unit would be slick if it still had the stock ram air effect.

 

Not necessarily. The hot side is only one factor. If the same size exhaust turbine has to spin a larger compressor wheel, it will spool a bit later b/c there is more mass to be moved.

 

It follows something known as Newton's Cooling curve ..... you can check it out in any advanced level physics books ..... the basic idea is things heat up or cool down when there is a greater difference in temp between 2 objects. But as the temps of the 2 objects come closer, it takes successively longer for a change in temp with respect to time. Or the rate of change of temp slows down with respect to time. Eg:
Rate of change of T = k (A-t)
Where k is a +ve constant >0, A is ambient temp and t is temperature of the object ......
The final formula to calculate the temp at any given time is exponential ... sorry but I'm too lazy to type that down. Hope this helps .....

 

Horrible dangerous idea that only slows the car down because it injests hotter underhood air and makes the BOV venting more audible. Mega ricey, IMO. Now there is nowhere for the water to go that comes through the hood extraction when you're cornering in the rain except straight through the filter and injested into the engine. Bravo!

Those of you that are saying that cooler denser air doesn't make more power, dyno with the correction factor off and learn something. This "mod" is bad news all around.

 

worst playa... the air gets heated... from a pretty much "infinite" (as far as fast rushing air is concerned) source of heat, so the cooling component comes after the turbo after the air has been heated. so if you have a colder intake charge, however much colder it could possibly be would that even make a difference, because it just gets heated, basically to the same temperature as if the cold air intake wasn't in place. am i right or wrong?

and all this about oxygen concentration. oxygen concentration is proportional to density, which is how much boost you're making, which doens't change even if the intake is sucking cold air. cold air is more dense... it'll just compress less to make the same boost pressure correct? just cuz yer air is colder doesn't mean it's more oxygenated, sucking cold air is no different from sucking hot air, it's the end pressure that dictates how much oxygen you get. am i right?

 

injesting water isn't a bad thing. other people have brought up that water logging your filter is bad, and i'd prolly agree with that, but injesting water is not bad. water going into your maf is prolly also bad too, but the engine can consume water, there's lots of water in gasoline (not the good ol' days of quarter a gallon leaded fuel) and of course i don't need to remind you of water injection.

 

robvii, I have that box and filter but I found it impossible to install. Any tips on installation?

 

In a way you are right, yes when the engine is under going the combustion process, the heat source is a continually replenished heat source. To give you a correct answer I would have to break it into a differential equation, that took into account the rate of flow of air, the temp difference between intake and the turbo, formula of newton's cooling curve .... you get the idea. But lets just guess this instead, I am pretty sure the rate of flow of air is pretty high, thus it would spend less time in the engine bay, turbo and exhaust. The reason is, we are using a turbo charged car that is sucking in lots of air. Now if the rate of air flow was slow it would get to absorb more heat. The turbo will be the part that will heat the intake air the most, because not only is the turbo hot dues to exhaust gasses, but it is compressing the air to a smaller volume and making it more dense (compression creates pressure which generates heat). I am guessing, if the incoming air was say 10 degress cooler the air would be a couple of degrees cooler (thinking less that 5 degrees C, hell it may only even be 1 C cooler) after it comes out of the turbo, compared to if the air was 10 C hotter, (I am totally guessing a may be completely off) and heads over to the intercooler to get cooled before reaching the engine. The thing is, a lot of factors affect this, ambient temp of environment, how fast the turbo is spinning (which in turn controls the rate of air flow), how fast the car is going, how hot the exhaust gasses are, temp inside engine bay, all these plus more affect the temp. Sorry I can't give you a yay or neigh but there is a chance it may help ... if all other things could be held constant then a dyno would tell us if this made more power ....
Density by itself does not give you pressure (which we measure using boost in PSI, bar, ...), temperature also plays a part .... There is a formula in physics
PV = nRT ...... this should help you out .... Therefore the amount of oxygen you are getting ultimately depends on the density of the air (give then percentage of oxygen stays constant in a given volume) and not pressure because the pressure of the air may be high, not because it is more dense but because it is less dense and at a much higher temp (molecules bouncing like crazy). Sorry I'm too lazy to type all I know .... I'ld probably do a better job talking to you in person. I hope I helped a bit .... personally I wouldn't do the air box hack

 

For the people who have done this mod, Have you dynoed the car to see if you lost or gained. I did the mod and it feels like it lost a little @ 3500-4000, but it did seem to pick up between 5000-7200 and on the freeway. You can hear the BOV between shifts which doesn't really matter to me, as long as this mod is picking up power and not losing it. I have been temping the filter and intake tube and it reads approximately 90-95deg with the outside temp being 72-75deg.