how Intercoolers work drift, street car

Turbo’s are a large part of the performance world because they offer a greater increase in horse power; they can also add a great deal of heat into a engine in which can risk damage to your engine. Depending on the size of the turbo, boost pressure and out side air temperature, the air that will enter the engine from the turbo can be anywhere between 100 and 200 degrees. Ideally we would like to get this temperature anywhere below 50 degrees. Heat has to minimised the most common way to do this is by installing a intercooler, there are two styles of intercoolers air/air and air/water.

A air/water system works by a core surrounded in water the air simply flows through the core and the water absorbs the heat, the water can absorb a lot more heat than air. The water then has to be cooled so it is than passed through a radiator, cooled then back to surround the core. The core surrounded in water can be placed anywhere in the engine bay which is good helping it to maximise flow into the intake manifold, The radiator needs to be placed where it will gain enough air flow to cool the water.

Air/water intercoolers are not as popular like the air/air. This is because of the water and the extra radiator will add weight to you car, also the air/water intercooler has a water pump the pump does not move the water until the switch is activated. The switch is commonly activated by boost pressure, throttle position or temperature, but before the water flows the turbo is most likely already on boost. Each time it passes through the core the water is heating up, therefore it will not be cooling as well until the water starts to flow.

An air/air system is very simple it is as simple as the hot air flows out of the turbo and into the intercooler, the movement of the car cools the air in the intercooler and the boost pressure pushes the cooled air around into the intake of the engine. It is very efficient to place the air/air intercooler at the front of the car to maximise the cold air flowing through the intercooler.

Choosing a size of an intercooler is vital, you need a large cooling surface but you do not want to sacrifice flow. Most cars have a factory intercooler normally just large enough to cool the air enough for the car to meet factory outputs and without putting the engine under any stress. An after market intercooler can be placed in the standard location and even the same size but offering an increase in cooling. This can be done by having a larger amount of fins per square inch or even offset fins to create more surface area. A good balance is also needed for flow.

If there is no pressure loss in the intercooler it is more than likely that the intercooler is too short and the air has not had enough time to cool. If the intercooler is too long there will be a pressure drop that is to large. If 20 psi (pounds per square inch) is going into a intercooler with off set fins as much as a 50% loss in flow can occur on the way out (10psi) with a straight fin intercooler you may only loose 25% flow (15psi) and if you use a straight fin and about 8 fins per inch you may only loose 10% pressure (18psi). Longer the intercooler the less fins per inch is needed because heat has a longer contact path.

It needs to be understood that the right intercooler has to be selected for the right application (Drift, Street, Drag or Dirt) so that you can gain maximum cooling and flow. Gaining the maximum cooling and flow can mean the greatest possible gain in horse power.