Usually, it is not necessary to upgrade the intercooler when raising boost levels. The pressure drop contributed by the intercooler is proportional to it's flow (CFM) squared. This relationship shows that it is highly unlikely the change resulting in loss from higher boost levels will require a larger intercooler. If there is a significant change however, such as 40% or 50%, then a larger intercooler may be necessary.

Pressure loss, or pressure drop, refers to the change in pressure when comparing the air entering the intercooler with the exiting air. This change is mostly affected by the internal flow area of the intercooler. Flow loss, however, is measured not just with pressure loss but with how much restriction to airflow exists. Maximum performance can be obtained if the pressure loss is kept below 1.0 to 1.5 psi. Anything in excess of these numbers, especially higher than 3.8 psi, and the intercooler is not properly fitted for the application which results in hindered performance and dramatically decreased functionality of the intercooler system itself.

Too small of a core, and you will restrict the potential of the turbo by not allowing the charge air to be cooled adequately.


Directly copied from Garrett. So you have a Greddy 18G on your car? Tell me more about how you have a properly sized cooler for your car....
Lets here this math you speak of...

You have just been served