The S55 turbo engine that powers the BMW M2C / M3 / M4 F8X has two air filter boxes that feeds the turbos with fresh air. The OE air filter boxes has panel filters that are quite small and therefore quite restrictive for the air flow.
DO88's goal when designing their new intake system was that it must be enclosed, so it does not draw hot air from the engine bay, which many aftermarket intake systems do. If the intake system draws hot air from the engine bay it is directly equated to warmer charge air (higher IAT). During all test DO88 carried out during the development of their entire BMW F8X M2C/M3/M4 product range, they saw clearly how the power band is directly equated with the IAT (Intake Air Temperature) and turbo inlet restriction.
When designing their upgraded intake system, they started with 3D scanning the engine bay on the M3 Competition. This gave them an exact 3D-model of the available space to design our intake system in.
DO88 found that they could use large double cone BMC air filters with large filtering area for higher flow. DO88 also use 3” (76mm) tubing designed with as few bends as possible to reduce the air flow restriction. To eliminate hot air from being drawn into the air filters DO88 designed heat shields and lids that together with rubber seals making the system feed the engine with cold air. The DO88 intake system uses the OEM air inlet ducts that feed the air filters with fresh air from the grill.
All these improvements have resulted in an impressive +10 hp top power gain and in the mid-range RPM saw gains up to +20 hp.
