Precise Oil Temperature Control for Your BMW Upgrade your BMW N20, N26, N51, N52, N53, N54, N55, and S55 engine's oil temperature control with Improved Racing's high-performance oil cooler adapter. Designed to address flaws in the factory's restrictive oil cooler adapter and faulty internal flow control valve, this upgrade ensures precise oil temperature control. Improved Racing's thermostat provides quick engine warmup, prevents overcooling, and delivers full oil cooling capacity on demand. Trusted by professional race teams around the globe, Improved Racing's thermostats have proven highly reliable, are backed by a lifetime manufacturers warranty, and are made in the USA. Option to Use the Factory Oil Cooler and Lines The optional factory oil line adapter allows you to use the factory oil cooler lines for a simple, plug-and-play installation. For maximum performance, the factory oil cooler and lines may be replaced with an aftermarket cooler and AN lines using the AN adapter fittings (-10AN line size is recommended). Please note that some applications, such as most BMW SUV's, use a water-to-oil heat exchangers. These applications require plugging the coolant supply and return ports, as well as adding an external air-to-oil cooler and lines (factory or aftermarket). Please note the EBW-100 adapter cannot be used without an oil cooler.