The BMW 335is comes from the factory with an auxiliary radiator smaller than a half sheet of paper. It will do little to keep the "limp mode" or heat soak away during a track day. The Dinan High Capacity Oil Cooler provides literally twice the volume of the stock unit, as well as 414 sq./in. of cooling tube vs. 112.5, and that's really just the beginning. Nicely integrated inlet ducting provides greater airflow efficiencies and the ventilation of air to the fender well has also been improved with a larger outlet. The system mounts neatly in the stock location and includes lightweight PTFE hoses with polyester outer braid fitted with race-quality fittings. For cars that were not equipped with the factory oil cooler, kits are available that include all of the additional parts necessary for the installation. The results of the oil cooler upgrade are quite significant, with the temperature gauge holding steady even under high load/high boost scenarios. And for those of you who track their cars, even occasionally, the Dinan oil cooler is a must.