Precision Raceworks Coolant Reservoir Cap | BMW B8 S4 3.0L SC V6 The threads are roll form

The threads are roll form tapped to create the toughest threads available and then stuffed with high-quality stainless ARP bolts to lock it all together

turbo outlet pipe

and a satisfying diverter valve blow-off noise

After applying the coating

Upgrading to stainless steel lines will provide a positive pedal feel

Precision Raceworks Coolant Reservoir Cap | BMW B8 S4 3.0L SC V6 The threads are roll formThe Precision Raceworks Engine Coolant Reservoir Cap is a functional and stunningly stylish way to add a nice touch to any engine bay! This cap come in three color options so there is always a color that will work for you! Black with Billet, Black with Blue, and the Stealth series (all black). Many people don't realize it but the OEM caps have a pressure release valve built into them. Often times aftermarket companies don't know this either or just