The BMW S55 engine produces fantastic power with very little lag from its twin turbos. The turbos keep a nice short pipe run to keep a quick throttle response, and BMW use an efficient charge cooler system to quickly drop the intake air temperatures before they enter the engine.
This works superbly on a standard car on the road and for short power runs on a dyno but can quickly become saturated when used hard on track or when running increased power levels. The charge cooler uses its own water supply and radiator to provide this much needed cooling and these are areas that can be improved.
We offer both Forge Motorsport which are based here in Gloucestershire, and leading US brand CSF.
The first option for improving the cooling on the S55 engine is to change the front heat exchange for a larger more efficient design.
We run the Forge Motorsport Heat exchanger on our own BMW M4 with great results.
The Forge heat exchanger offers a significant increase in core surface area and volume (545x460x32mm) over the standard cooler.
Other features are as follows:
FRONT MOUNT HEAT EXCHANGER (CSF #8075 / #8075R)
Features:
For cars looking for further improvements to the cooling capacity of the charge air system both Forge Motorsport and CSF offer larger Charge Coolers.
In addition to the Forge Motorsport Heat Exchanger they also provide a complete top mount replacement chargecooler and expansion tank for the BMW S55 Engine.
The chargecooler features an all-aluminium construction which overcomes all the issues relating to plastic end tank splitting, failure at high boost and leaks between the core and end tanks with end tank seal failure. The end tanks are fabricated using high precision laser cut sheet metal panels which are TIG welded by hand for maximum strength and durability.
Designed and manufactured at Forge Motorsport HQ in Gloucestershire, England, we utilised our Solidworks CAD design system to assist in the creation, modification, CFD (Computational Fluid Dynamics) analysis and optimization of this innovative charge cooler. Three different core constructions were evaluated during the development process. The final design of a bar and plate core far outperformed the other two alternatives. In doing this, the Forge Motorsport development engineers have made a quadruple pass design, allowing the water to flow through four passes of the cooler which improves the cooling efficiency beyond any other products currently on the market.
Unique to the market, the Forge BMW M2 Competition/M3/M4 S55 Chargecooler system uses an expansion tank rather than a header tank like the OEM system. There is a filler cap located at the highest point on the Chargecooler allowing you to be sure that the charge is 100% full of coolant with no air pockets. This maximises the efficiency of the heat rejection of the coolant within the Chargecooler water jacket.
Features:
For the serious trackday customers we would also recommend installing the CSF DCT Transmission cooler. We run a similar version to this on our BMW M3 E92 DCT track car and it has significantly reduced the DCT oil temperature.