The Willys L134 (nicknamed Go Devil) was a straight-4 automobile engine made famous in the Jeep produced in World War II. The engine displaced 134.22 cu in (2,199.5 cc) with a 3.125 in (79.4 mm) bore and 4.375 in (111.1 mm) stroke, a very undersquare design. It was an L-head design, with valves parallel to the cylinders. Initial power output was 60 hp (45 kW) at 4000 rpm and 105 ft·lbf (142 N·m) at 2000 rpm with 6.48:1 compression.

The L134 was phased out by the F-head Willys Hurricane engine beginning in 1950.