Like the human body a car has an internal temperature it needs to maintain to work at peak efficiency. To your car a track day is like running a marathon. Imagine running a marathon without drinking any water, you’d overheat and collapse without even finishing right? If your car can’t adequately keep its fluids cool on the track then the same thing happens, possibly damaging the engine internals in the process. Luckily with the M2 there are safety features which limit the car’s power before major overheating occurs, but then you’re stuck in limp mode waiting for it to cool off. No one wants to waste half their session in the pits while their car is cooling off, wouldn’t it be prudent to take precautions and prevent it even happening in the first place?
BMW M2 at the track
Fortunately CSF knows the importance of cooling and has come out with a set of 4 coolers that are track tested and proven. They are all made as direct replacements for their OEM counterparts, so all connections, brackets, hoses, etc will attach easily for a painless drop-in install. They all cost the same to purchase so there is no monetary benefit of choosing a particular one in terms of initial money out of pocket. We’ll provide an overview of each part’s benefits and go over which ones we recommend you prioritize if you don’t want/need all of them.
Oil coolers are are a common upgrade among enthusiasts no matter what car they drive. This is due to the fact that while oil helps remove excess heat from your engine, its primary purpose is to lubricate the moving parts of the engine. Oil’s high viscosity plays a large part in its ability to lubricate and protect the various engine components it is responsible for. If oil gets too hot it will lose some of that viscosity and allow more friction between moving parts. This is why having an efficient oil cooler is important when tracking your car. Cooler engine oil will keep all your internals running smoothly and will help keep the overall temperature of your engine within the operating range.
The CSF Oil Cooler was designed with hard track days in mind so they’ve worked hard to get the best cooling possible. To increase the volume of oil passing through the cooler, two cooling tubes/rows were added to the front core (17 vs OEM’s 15). A second core with 6 additional rows was then added for a total gain of 8 rows, a surface area gain of over 50%. Additionally this oil cooler utilizes a high density multi-louvered fin design (see beelow) to maximize surface area. This design has been thoroughly tested in CSF’s wind tunnel and found to be the most efficient fin shape to maximize airflow wile removing the largest amount of heat.
CSF’s multi-louvered fin design
Out on the track CSF’s testing proved accurate as they were able to achieve maximum oil temps of 240°F in 103°F ambient. This is a big improvement over the 275-280°F oil temps they were seeing with the OEM cooler which caused the car to go into limp mode. Because your engine oil is so important for both cooling and maintaining your engine internals we recommend prioritizing it because it does have the potential to save you money on maintenance in the long run.
The CSF DCT Cooler is the next important upgrade for those of you who purchased your M2 with the dual clutch transmission. Lightning fast shifting and keeping your hands on the steering wheel at all times are huge advantages on the track, but they do come with a downside. Dual clutch transmissions use type of oil to control all the solenoids and actions performed by the transmission much like a standard automatic transmission. A transmission cooler is necessary because this oil or “transmission fluid” will heat up from the normal operation of the DCT. The hotter the transmission fluid gets the more it loses its viscosity which will affect shifting and lubrication of the internals.
Single-Pass vs Dual-Pass flow
Sounds a bit familiar right? We recommend the CSF DCT Cooler because not only does it keep your transmission out of limp mode on the track, it also helps with the longevity of your transmission. This particular cooler uses over double the rows of the OEM trans cooler (12 vs 6) and is set up in a dual-pass configuration(see illustration above). This setup effectively doubles the path of the transmission fluid, exposing it to ambient air longer and cooling it further. The fin design is the same multi-louvered design as the oil cooler and provides the same benefits. The overall design was lab tested by CSF and shown to be approximately 40% more efficient than the OEM cooler. When you’re out on the track this can make the difference between setting a personal best or sulking on the sidelines while your car is stuck in limp mode.
Now that you’re pretty well prepared to avoid limp mode you want to consider equipping your car to get the most out of other modifications. The CSF High Performance Intercooler is where to look if you want to maximize the potential of the air being propelled by the turbocharger. Anyone who is not familiar with what an intercooler is here’s a very brief non-scientific explanation. When air passes through a turbo or a supercharger it is being compressed to increase the pressure of the air entering the engine (which is why boost is measured in pounds per square inch). This compression generates a lot of heat which then needs to be removed by the intercooler to avoid damage to the motor from pre-detonation. The reason you would want a bigger intercooler is to cool the air even further. Cooler air is denser and will burn better resulting in more power.
In the case of the CSF High Performance Intercooler the company has gone to great lengths to maximize benefits while maintaining the drop-in fit design. CSF used a stepped core design to utilize the open space in front of the OEM intercooler. This design increases the surface area significantly along with the internal air-flow volume. The front face bar design optimizes airflow through the core for further cooling on top of the extra volume and surface area. The result is a huge boost in efficiency showing a drop of up to 40°F intercooler temps and CSF reports power gains of 15-20HP on stock components and 25+ on modified vehicles. More consistent power is always nice and a lot of people will opt for buying this upgrade first/only, but if you’re a serious track enthusiast we do recommend protecting your engine and transmission before worrying about power.
The fourth and final piece CSF makes for the M2 is their High Performance Radiator. The M2’s OEM radiator will get you by on the track at first but it has its limitations. The CSF Radiator features a 42mm 2-row core in a triple-pass configuration. Like the double-pass found on the DCT cooler, triple-pass allows a given amount of coolant much more access to the radiating surface area, thus allowing the release of more heat. Along with the cooling benefits this radiator also has stamped aluminum end-tanks which are much more durable than the plastic end tanks on the OEM radiator. Plastic becomes brittle when it gets very hot so the harder you drive your car the quicker your factory radiator will have a failure. If you upgrade it you reduce your coolant temps and avoid a failure at the same time.
Blue BMW M2 on a mountain pass
Although these products are very much track oriented the High Performance Intercooler and High Performance Radiator do have some non-track benefits to them. The intercooler would be great for the street driving enthusiast who lives in a hot climate and wants their M2 to maintain consistent power in the heat. The high performance radiator would be a solid buy for those in similarly hot climates who want to get rid of the OEM radiator with plastic endtanks. This is not as big a concern for most as it would be on the track, but it’s still not a bad idea if you plan on keeping the car for years to come. Because the M2 already comes with an oil cooler and DCT cooler (where applicable) it is not particularly necessary to install upgraded versions for non-track applications.
Blue BMW M2 on a mountain pass
We hope this information has been helpful to those of you who weren’t quite sure what cooling upgrades to prioritize for the M2. If you have any questions about these or any other upgrades for your car, our Mod Experts are always happy to help. You can reach us at (714)-582-3330 or by email at [email protected].