The Mazda Factory Race (MFR) High Performance Rear Oil Pressure Regulator interchanges exactly with the stock rear oil pressure regulator on all 1971-2010 12A, 13B, and 20B engines. It is designed to bypass at 105-115 PSI. (Pressure this high should be used only for racing). When using this regulator, the front pressure regulator should be shimmed an 1/8-inch to ensure that it does not limit the oil pressure (shims included).

Made in the USA by Racing Beat, Inc.