The first significant bolt-on cooling upgrade for the Tesla Model 3

A plug-and-play oil cooler using trusted motorsport proven components that really works, with ZERO compromises.

• Setrab oil cooler core
• Built-in 342cfm fan 
• Motorsport Aeroquip Starlite hoses with crimped fittings, as found on professional level motorsport vehicles.
• CNC machined, MPP designed oil filter plate specifically designed for the Model 3’s drive unit
• Included 1/8″ NPT port for temperature sensing or switching control of the fan
• Laser-cut aluminum brackets included for a plug and play install
• Massive heat rejection from this cooler, one of the first MPP.R cooling upgrades to come for enhanced endurance.
• Made in Canada (brackets and filter plate), the USA (oil lines) and Sweden (oil cooler)

The Model 3 has a very intricate cooling system which is composed of many different systems that interact in a dynamic way – that is to say, it’s not like your typical internal combustion engine with one coolant loop and one radiator! The Model 3 has a valve that can direct coolant through two different paths, an AC compressor that can run to cool down the coolant, and flaps that can block airflow to the radiator. On the oil side of the system – each drive unit has an electric oil pump which varies its flow, and this oil goes through a heat exchanger that transfers heat from the oil to the coolant system on the Model 3.

The purpose of the oil on the Model 3 rear-drive unit is to remove heat from the stator (the outer part of the motor) and the rotor (the center of the motor). The drive unit oil also lubricates and cools the gear reduction and differential. These are the hottest parts of the system, and as such on the racetrack the drive unit oil is the hottest fluid on the vehicle.

The stator and rotor are also where limits of the rear drive unit commonly show up, as the stator and the magnet inside the rotor are the items that exceed their thermal limits on the racetrack. These limits are quite high – with the stator being allowed to run at around 115 degrees C.

On the opposite end of the spectrum, we have the battery, which is thermally limited around 60 degrees C, but has such a small amount of thermal transfer due to the small interface of the cooling channels against the battery cells, that coolant temperatures around 30 degrees C are really required to keep the battery cool while on track. This is where the AC system comes into play, as it is able to cool the battery water loop sub-ambient temperatures.

Under normal track circumstances, the Tesla cooling system will focus the AC compressor’s cooling output to the battery, lowering the battery coolant temperature. The radiator will be solely in charge of cooling both drive units. Eventually, the powertrain gets too hot, and the system needs to use the AC compressor to cool both the powertrain and the battery, at which point the system quickly overheats as the battery inlet temperature rises, resulting in battery limiting.

Understanding the above, it made sense that an oil cooler would be the perfect method to remove a huge amount of heat efficiently, as the difference in temperature between the oil and the air would be very high, even on hot days. The heat removed from the oil cooler would effectively be heat no longer going into the powertrain loop, as the heat exchanger between the oil system and the powertrain loop is located after the oil cooler. This will lower the water temperature of the system – which in turn will lower the inverter temperatures, and the temperature of air passing through the AC condenser, as that is located behind the radiator. This would increase the AC system efficiency which in theory would help with battery cooling.

That was the theory, and we’re proud to say that in practice we found similar results. The best comparison would be on our Long Range RWD car with the AC compressor disabled. Without the oil cooler, the rear drive unit would overheat in two laps (3 minutes). With the oil cooler and the AC compressor still totally disabled, the rear drive unit only started to mildly pull power after 15 minutes. So there is absolutely no question about whether or not the oil cooler is removing heat from the system, it is plainly obvious if you put your hand behind the fan and feel how much heat is coming off of the cooler when the oil temperatures are 60 degrees C