do88 performance intercooler designed for a drop-in fit in the BMW M2 / M3 / M4 F8X The BMW M2C / M3 / M4 F8X has a twin-turbo engine (S55) that uses a top-mounted water-cooled intercooler instead of a “conventional” air-cooled intercooler. The original intercooler has a Tube & Fin core with plastic tanks that are crimped on. This design has its drawbacks, as it is prone to cracking and to leaking coolant into the engine intake, or to losing boost pressure through the seal between the plastic tanks and the core. Our goal when we started developing our new intercooler was to eliminate every weakness in the original intercooler's design and, of course, to raise performance substantially. Throughout all the tests carried out while developing our entire BMW F8X M2C / M3 / M4 product range, it is clear how directly power is linked to intake temperature. To obtain an accurate 3D model of the space available for the intercooler, we made a detailed 3D scan of the engine bay in our own BMW M3 Competition. In our Solidworks CAD software we worked through several different design concepts for the new intercooler using the 3D-scanned model. The final design concept was settled after several CFD simulations in our Solidworks Flow Simulation software. This software lets us simulate airflow and measure pressure drop and air/water distribution across the core. We decided not to include internal air guides, as several of our simulations showed that they did more harm than good. With our tank design the airflow is distributed perfectly across the core, without the internal air guides that many others in the industry claim to be beneficial. Our conclusion is that in this case these air guides cause turbulence and disturbance in the airflow. The final design has a bar-and-plate core with TIG-welded cast aluminium tanks. This gives peace of mind to anyone with high power targets (high boost pressure). We managed to use a core that is a full 85% larger than the original and also to reduce the pressure drop (16% lower). Despite this, the installation remains drop-in with no modifications. A lower pressure drop across the intercooler has several benefits, for example the turbo has to work less to reach the requested boost pressure / it contributes to lower temperatures / it improves throttle response. We have the equipment to calculate pressure drop in our CFD software and also to measure it in real-world tests on our Superflow SF-1020 flow bench. For the coolant we changed the flow path so that it passes through the core twice before leaving the intercooler, instead of once as on the original intercooler. In the core we use high-density offset cooling fins on both the air and the water side. Several tests were carried out to find an optimal balance between the air and water fins, to obtain maximum heat transfer together with a low pressure drop. This gives our intercooler an enormous increase in active cooling area compared with the original. As this is a do88 performance product, we have of course carried out thorough testing while developing it to ensure the best performance. No compromises have been made. All this hard work results in a product that will genuinely improve the vehicle's performance one way or another, whether it is a standard car or a heavily modified monster! On the road, on the street, on the track, this intercooler will be a true companion! Key benefits of the do88 performance intercooler (comparison value: original part): - Peak power increase of 13 hp! Measured on a car with BootMod3 stage 1 software. - Highest mid-range power increase of 25 hp! - Highest torque increase of 52 Nm! - Larger core: 5657 cm3 (3052 cm3), 85% larger! - Airflow at 0.025 bar / 0.36 psi pressure drop: 298 CFM (256 CFM), 16% higher! - Lower temperature after the intercooler under the same test conditions: 39°C (48°C). 9°C lower! * * Measured at 240 km/h during full acceleration 0-240 km/h at an airfield. Both tests were carried out on the same day under the same conditions.