In the hart of Jeep there was very strong and reliable engine "Go Devil" The power and torque of the L-Head engine is arguably the main reason Willys won the contract with the DOD to produce the MB used in WWII. It doesn't seem like much by today's standards, but it out performed the engines used in the Ford and Bantam prototypes. The MB used a different carburetor from the civilian models.
The L-Head is known as the L-Head because the valves for the exhaust and intake are in the block. Most engines used in automobiles today have valves in the head. This design gave it the advantage of having a relatively low profile. Part of the DOD specifications required the vehicle to be able to drive under an object that was about 3 feet high.
The L-Head engines uses a cast iron block and cylinder head with 3 main bearings and mechanical lifters. The "Go Devil" engine earned its fame in the MB use in WWII. The L-Head continued to be used in the post War CJ-2A, Willys Wagon, Willys Pickup, CJ-3A, M38, and DJ-3A. The specifications are slightly different presumably due to carburetor and compression differences between the engines. The L-Head used in '45-'50 CJ-2As and '49-'50 CJ-3As is rated the same.
| L-Head 134 4 Cylinder | |
|---|---|
| Bore x Stroke | 3.125" x 4.375" |
| Displacement | 134.2 ci(2.2L) |
| Compression Ratio | 6.48:1 |
| Horsepower (gross) | 60@4000rpm |
| Torque (gross) | 105@2000 |
| Main Bearings | 3 |
| Valve Configuration | L-head |
| Fuel | Carter WO-596S 1bbl downdraft |
Super Hurricane L-Head 226 I6
The "Super Hurricane" 226 L-Head engine has a cast iron block and cylinder head with 4 main bearings and solid lifters. The exhaust and intake valves are in the block, not in the cylinder head. The engine was used in earlier Willys cars, but was first introduced in 1950 in Willys trucks. The Willys Pickup and Willys Wagon used the 226 from '54 until '63. There was an option 7.3:1 high altitude version available during these years.
The 226 used between 1954-1958 has a slightly higher horse power rating than the later 226.
| Super Hurricane L-Head 226 I6 | |
|---|---|
| Bore x Stroke | 3.94" x 4.375" |
| Displacement | 226.2 Cubic Inches |
| Compression Ratio | 6.861:1 |
| Horsepower (gross) | 115@3800rpm |
| Torque (gross) | 190@1800 |
| Main Bearings | 4 |
| Valve Configuration | L-head |
| Fuel | 1-bbl Carter |
The F-Head 134 inline 4 was the standard engine in the CJ-5 and CJ-6 from their introduction until 1971. The F-Head was the only engine ever used in the CJ-3B. The engine also saw action in starting in the middle of 1950 in Willys Wagons and Willys Pickups. It was also used in FC trucks.
The F-Head 134 uses a cast iron block and head with mechanical lifters and 3 main bearings. Two versions of the F-Head were available most years, the output specifications are the same for both, the compression is different. The intake valves are in the head, but the exhaust valves are in the block. The valve configuration makes the F-Head engine taller than the L-Head because the L-Head has the intake and exhaust valves in the block.
New engine compartments had to be designed to make room for the taller engine. The CJ-5 and CJ-3B were designed with this engine in mind. It is fairly common to see a F-Head engine swapped into a CJ-2A or CJ-3A. Normally a section of the hood is cut out to make room for the carburetor.
There is a lot of confusion about the name of the F-Head engine. The F represents the valve configuration where one set of valves is in the head and one is in the block. The "F" in F-Head does not stand for "Flat" nor does it stand for "Ford". Other makes of vehicles used flat head engines and some people think the F-Head stands for flat head. Another source of confusion is Ford built some of their WWII GPWs with bolts with an "F" on the head so the parts could be distinguished from the Willys MB. They used F head bolts to build the GPW, but this is not related to the F-Head engine.
The main difference between different versions of the F-Head engine is the compression. The early F-Heads used between '50-'60 in Willys Wagons, Willys Pickups, CJ-5s, CJ-3B, etc had a low compression F-Head standard. The Willys Pickup only used this engine from '50-'56 and in '59.
| Hurricane F-Head 134 I4 | |
|---|---|
| Bore x Stroke | 3.125" x 4.375" |
| Displacement | 134.2 (2.199L) |
| Compression Ratio | 6.9:1 |
| Horsepower (gross) | 72@4000rpm |
| Torque (gross) | 114@2000 |
| Main Bearings | 3 |
| Valve Configuration | F-head |
| Fuel | 1-bbl Carter |
