The S55 turbo engine that powers the BMW M2C / M3 / M4 F8X uses a Top mounted water-cooled intercooler instead of an “regular” air-cooled intercooler. The coolant in this system has its own separate cooling circuit combined of two parallel connected radiators and a pump. The larger one of these two parallel connected radiators is positioned in the front of the center cooling module, the second smaller one is located in front of the right-side wheel arch.
Reducing the water temperature in this circuit is directly equated with improved cooling of the charge air (lower IAT). Due to this reason, it is important to have high performance radiators in this system to maintain as low and stable IAT as possible during tough driving. During all test we have carried out during the development of our entire BMW F8X M2C/M3/M4 product range we see clearly how the peak power is directly equated with the IAT (Intake Air Temperature).