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

The "High Altitude" option was the same engine with a higher compression ratio.

Hurricane F-Head 134 I4
Bore x Stroke	3.125" x 4.375"
Displacement	134.2 (2.199L)
Compression Ratio	7.4:1
Horsepower (gross)	72@4000rpm
Torque (gross)	114@2000
Main Bearings	3
Valve Configuration	F-head
Fuel	1-bbl Carter

Between 1961 and 1970, the high compression version became standard and the low compression version was optional. A slight horse power gain was realized. The Willys Pickup used the 7.4:1 compression engine as standard and a 7.8:1 compression engine as optional from '60-'62.

Hurricane F-Head 134 I4
Bore x Stroke	3.125" x 4.375"
Displacement	134.2 (2.199L)
Compression Ratio	7.4:1
Horsepower (gross)	75@4000rpm
Torque (gross)	114@2000
Main Bearings	3
Valve Configuration	F-head
Fuel	1-bbl downdraft

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)	75@4000rpm
Torque (gross)	114@2000
Main Bearings	3
Valve Configuration	F-head
Fuel	1-bbl downdraft

In 1971, a low compression version was the only one available in the 49 state version. A California version was high compression.

Hurricane F-Head 134 I4
Bore x Stroke	3.125" x 4.375"
Displacement	134.2 (2.199L)
Compression Ratio	6.7:1
Horsepower (gross)	75@4000rpm
Torque (gross)	114@2000
Main Bearings	3
Valve Configuration	F-head
Fuel	1-bbl downdraft

The California high compression F-Head available in 1971.

Hurricane F-Head 134 I4
Bore x Stroke	3.125" x 4.375"
Displacement	134.2 (2.199L)
Compression Ratio	7.4:1
Horsepower (gross)	75@4000rpm
Torque (gross)	114@2000
Main Bearings	3
Valve Configuration	F-head
Fuel	1-bbl downdraft

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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 todays standards, but it out performed the engines used in the Ford and Bantam prototypes. The MB used a different carburetor from the civilian models and currently I do not have the percise specs on it, but it is right in this same range.

The L-Head is known as the L-Head becase 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

The L-Head used in 1947 until mid 1950 Willys Pickups and Willys Wagons has a slightly higher torque rating. It uses a different carburetor and has different compression.

L-Head 134 4 Cylinder
Bore x Stroke	3.125" x 4.375"
Displacement	134.2 ci(2.2L)
Compression Ratio	6.47:1
Horsepower (gross)	60@4000rpm
Torque (gross)	106@2000
Main Bearings	3
Valve Configuration	L-head
Fuel	Carter 626 1bbl

A high altitude version of the L-Head was optional with the Willys Pickup and Willys Wagon.

L-Head 134 4 Cylinder
Bore x Stroke	3.125" x 4.375"
Displacement	134.2 ci(2.2L)
Compression Ratio	7.0:1
Horsepower (gross)	60@4000rpm
Torque (gross)	106@2000
Main Bearings	3
Valve Configuration	L-head
Fuel	Carter 626 1bbl

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Posted by:
Opie Bennett
E-mail opiebennett@gmail.com
XJ_Ranger on NAXJA and Pirate Bulletin Board and Early CJ-5


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