Do88 high performance radiator for intercooler system designed for easy assembly for BMW M3 / M4 F8X

The S55 turbo engine that powers the BMW M3/M4 F8X uses a top-mounted water-cooled intercooler instead of a “normal” air-cooled intercooler. The coolant in this system has its own separate cooling circuit combined by two radiators connected in parallel and a pump. The larger of these two radiators connected in parallel is positioned in the front part of the central cooling module, the second smaller one is located in front of the right wheel arch.

The reduction of the water temperature in this circuit is directly equated with better cooling of the charge air (lower IAT). For this reason, it is important to have high-performance radiators in this system to keep the IAT as low and stable as possible during hard driving. During all the tests carried out, it was clearly noted that the peak power is directly equated with the IAT (Intake Air Temperature).

The final design has a 68mm thick dual row core with multi-channel tubing and the OEM style single pass flow layout has been retained. This design extends both the height and thickness of the core by 28mm – all of which translates to an increase in frontal area by 18% and core volume by a whopping 100%. To make the installation of this huge radiator possible, we designed a beautiful carbon fiber air duct produced with prepeg material in the autoclave process. Our radiator has a drop-in installation with OEM cooling lines.

These improvements have resulted in an IAT reduction of 5°C, combined with the side-mounted radiator upgrade.

Significant advantages of the do88 radiator (stock comparison numbers):
– Larger core volume: 3393 cm3 (1693 cm3), 100% larger!
– Greater frontal surface area: 499cm2 (423cm2), 18% larger!
– Lower post-intercooler air temperature under the same conditions: 34°C (39°C), 5°C lower!*
– High efficiency core with 8mm fin height of multi-slot design.
– Multi-channel central pipes

* Measured at 240 km/h during full throttle acceleration 0-240 km/h on the air track. Both tests were performed on the same day under the same conditions.