Ford built the first Hemi.

Chrysler fans claim that there first hemi was the 1945 experimental V16 aircraft engine. Code named "XIV-2220", this two-valve per cylinder engine produced 2,500hp.

Fords first hemi engine was six years earlier in 1939 when Rolls Royce sent blueprints, tooling and parts to Ford to build the Marlin V12 aircraft engine, Ford immediately started to redesign the Merlin, two very modified hemi headed engines were built in their prototype shop. Rolls Royce did not approve of the changes and Henry Ford’s insistence that Ford only manufacture for U.S defense caused the Merlin production to be moved to Packard, who subsequently built about 58,000 Merlin’s. Ford built their own V12 engine in 1940. More on this other Ford Hemi next.

In early 1942, the Army requested a version of Fords V-12 aircraft engine for Sherman Tanks to replace the previous unreliable aircraft type air cooled radial and the convoluted 30 cylinder Chrysler engine (5 Dodge Flathead six cylinder blocks around a common shaft).

Ford removed the fuel injection but retained the aluminum construction, the 60 degree banks, shortened the blocks to eight cylinders and ultimately produced 29,000 1100 cubic inch GAA Sherman Tank, GAF Pershing Tank, and GAN Tank Destroyer engines. The Ford V8 Tank engine has a 180 degree “flat” crankshaft, which results in each bank operating as a separate 4 cylinder engine. Ignition was by two 4 cylinder magnetos, each sparking an individual bank. It was designed this way so that if one side of the engine was damaged, the vehicle could still operate. The GAA engine was a great adaptation for the tanks it powered, with excellent, innovative gear drives for fans, pumps, etc. The Tank crews discovered that if they disconnected the governors, the engine would rev up to about 3800 RPM before the valve springs floated and the Tank would do about 60 MPH! They are also extremely tough and reliable and adapted for post-war use in oil fields, irrigation pumps, in boats, trucks and heavy machinery. Because of its unequaled performance, the motor was banned from drag racing in the 1950s. Remaining numbers of GAA and variants are estimated at between 500 to several thousand worldwide, as the Tanks were still in foreign military service into the 1980s. The V8 GAA’s continuous duty output was 525HP @ 2800 RPM with 1000 ft/lbs of Torque from 2000-2600 RPM upward.

Good history lesson!