DESIGN

Since it has been posted before about what a CAI does, here is a related question. What would happen if you were to run an intercooler inline with your intake system? I could use a stock intercooler of any number of cars. I am not looking for one of those giant front mounted intercoolers. This is not for looks. Would the intercooler lower my intake temperature significantly? I do not have a CAI yet. I am only interested currently in N/A power and this seems like a plausible idea.

Random

It works in Simple theory....But when you go into complex theory...it fails.

If it is 70 Degres outside, a CAI will suck in 70 degree air. SO your engine should be ingesting 75 degree air. The reason for the 5 degree increase is due to The CAI heating up, the Throttle Body Heating up...the Intake manifold heating up..etc...etc..etc.

Using the Same Senario...if you have an intercooler you suck in 70 degree air...the intercooler had 70 degree air blowing over it....No tempature drop. Then the engine would be ingesting 75 degree air for the same reasons stated above.

Using air to air intercooler...you cannot cool air any colder than the outside air tempature. (usually around 70 Degrees)

Using water to air intercooler, you cannot cool air any colder that the coldest coolant tempature....(150 to 180 Degrees)

Brendan

Intercoolers are meant for a turbo at 500 degrees, there is also restriction in them making it less desirable for a N/A car.

DESIGN

Would it then be better to insulate the entire fuel/air delivery system? That is if it possible. I realize that the reason that forced aspiration requires cooling is that the air is heated as it is compressed. Would the extended surface area of an intercooler not allow the air to cool even more than the outside air? I believe you may be saying that since the air was never heated above the outside air temp that it would be impossible to cool it any more. I bow to your greater knowledge Random but, I may research this further.

Random

If outside air is 70 Degress, you will never cool your intake charge below 70 degrees using only air to air. It's simply not possible.

A 70 Degree objected placed in a 70 degree room, will be...70 degrees. 2 hours later it will be 70 degrees. If you blow 70 degree air over it...24 hours later it will be 70 degrees.

I think you are confusing moving air, with the evaportative powers of water.

You can introduce a fine water mist into the air stream. The evaporative effect of the water would lower the air tempature. As the water droplets evaporate they absorb heat, it that lowers the air temp.

Using this method, you can lower the intake air stream below 70 degrees(Ambient temp). You can also do this to a limited degree by spraying water on the outside of the intercooler itself. the evaporitive effect can cool the metal of the intercooler below the tempature of the outside air in addition to cooling the air travling through the intercooler....but only by about 5 or 10 degrees...and only on really hot days. Since most air to air intercoolers are only 60 to 70% efficent, they would not lower the air temp below outside temps by more than a degree or two.

Hardly worth the extra plumbing, and hardly worth the extra work you put the engine through...forcing it to litterally suck through a 5' long straw with an intercooler in the middle of it...

DESIGN

Thanks Random.

SlowTibby

maybe if you hookup your ac to your intake...
;P

Random

Believe it or not, that is not such a crazy idea. One of the benefits of Nitrous, is that it cools the intake air charge. When you take a pressurized gas, and release the pressure...the gas comes out as low tempature. This cools the intake air charge.

There are also various different "water" injection systems. These spray or inject an ultra fine mist of water into the intake air stream. The water evaporating cools the intake air, and also water vapor acts to raise the octane level of your fuel to prevent detnotation.

Curtas

I've read of people who have tried this (A/C in the intake) . . . the power loss from the compressor always outweighs the power increase.

The mister is a good idea, similar to the concept of methanol injection (although methanol burns and water does not). I think the hassle (and expense) are better put to getting a better intake, TB, manifold, and headers (don't forget boost smile.gif )

AC