Fuel injection
Six months after the M20 was launched with the carburetted M20B20, the larger, fuel-injected M20B23 was introduced for March 1978. The initial version of the M20B23 uses the same head (known as "200") and block as the M20B20 but a longer stroke crank. The bore is and it has a capacity of . Fuel injection was K-Jetronic, the compression ratio is 9.5:1 and the redline is 6,400 rpm.