Wagner Tuning Competition Intercooler BMW M2 M3 M4 F80 F82 F87 S55 | AustraliaThe 3. 0 L S55B30 Twin Turbo engine in the BMW M3 M4 M2C models is equipped with an indirect charge air cooling system. So the cooling of the charged air is not cooled by the ambient air as like the conventional intercooler set ups. Charge air cooling is courtesy of water to air cooling set up. A reduction of the temperature of the cooling water is directly equated with an improved cooling performance of the charged air. This is exactly where the