10-03-2012, 05:45 PM
hang up and drive!
Join Date: Sep 2009
Mein Auto: 335d
In the interest of sharing some basic knowledge on IC's, allow me to offer this:
The turbo charger is a simple rotary (centrifugal) air compressor. It draws in outside ambient air through the air filter. As air is compressed it gets hot and increases in both pressure and temperature, but decreases in volume. The IC (Intercooler) then cools this compressed air back down to a lower temperature, but it is still hotter than original ambient air. I don't have any of the exact temps and pressures to throw out here.
The intercooler is in turn cooled by either ambient air flowing through tube fins or by engine cooling water that was previously cooled by the radiator which is a water tubed fin cooler. Either way it lowers the compressed air (now known as charge air) temperature prior to it entering the cylinder via the intake valve.
The whole purpose of this is to pack more air into a smaller space so you can then inject more fuel and get a bigger explosion (or expansion) and make an otherwise boring engine into a vehicle we like to call the 335D.
My Garmin Ecoroute HD shows me ambient air and intake air temp, so I can see what is the Delta T and thus have an idea how the intercooler is performing. The purpose of installing an aftermarket IC is to allow the charge air temp to be dropped even lower which increases air density (more air in same volume of space, i.e. an engine cylinder) which in turn allows for a bit more fuel, and thus an increase in power. It may also be just to keep things from running too hot as in the racing world where you are pushing things to their limit.
This is not the case for our cars running at 80mph on an open highway. Which is most likely what the engineer's are designing to. But certainly there is plenty of margin to handle the occasional boost of power we demand of our cars from time to time.
If you plan to race, you would most likely want and need better intercooling capacity than what our cars come with.
If you are a racing fanatic (which I am not) I suppose you might want to keep close records or logs of these parameters so you know what you may need to be doing to your engine to get more out of it.
If I've told you something you already knew, I apologize.
2010 Black 335D Sport/Premium, Michelin PSS 235/265
2000 Silver Z3 3.0i (Ret)
1999 Silver R1200C (Ret)
1968 Black 1600 Coupe (Ret)
Last edited by Flyingman; 10-03-2012 at 05:46 PM.