The Lightning engine is a Willys straight-6 produced in the 1940s and 1950s. The flathead engine featured four main bearings and solid valve lifters.
The engines were used in the Willys Jeep Station Wagon, other Jeep-based vehicles, and Willys sedans.
L148
The L148 version displaced and was rated at .
Applications:
- 1947-1950 Willys Jeep Station Wagon
- 1948 Willys-Overland Jeepster
L161
The L161 version displaced and was rated at . Introduced in April 1950, the engine featured a higher compression ratio of 6.9 to 1, and a larger bore.
- 1953-1955 Willys Aero-Falcon
Replacement
The F-head Hurricane engine was introduced in 1950, a significant upgrade to the Lightning. The valve configuration was changed for better power and efficiency. In 1954, the 6-226 "Super" Hurricane was introduced.