Italian automobile company Lancia was the first to manufacture cars with V4 and V6 engines in series-production. This started with a number of V4-engine families, that were produced from the 1920s through 1970s.
The Lancia V4 pioneered the narrow-angle V engine design, more recently seen in Volkswagen's VR5 and VR6 engines. By using very shallow V-angles — between 10° and 20° — both rows of cylinders could be housed in an engine block with a single cylinder head, like a straight engine. A determining characteristic was the use of overhead camshafts (either single or double), in which a camshaft would serve the same function for all cylinders — in "both" cylinder banks.
Lambda.
The first V4 was used in the Lambda from 1922 through 1931. It was a 20° narrow-angle aluminium design. All three engine displacements shared the same long stroke, and all were SOHC designs with a single camshaft serving both banks of cylinders.
Engines:
Artena.
The Lambda engine was updated for the Artena. Bore was set at as in the 2.6 L Lambda, but stroke was reduced to a more conventional . Total displacement was , with produced at 4000 rpm.
Augusta.
An all-new V4 was designed for the Augusta. Produced from 1934 through 1938, the Augusta's engine displaced with a bore and stroke. Power output was at 4000 rpm.
Aprilia.
The engine was redesigned again for 1936's Aprilia. The first-series cars used a version with a bore and stroke. Output was at 4300 rpm.
A second series was unveiled for 1939 with an enlarged engine. It did not share its predecessor's dimensions, with bore and stroke now at . Power output was nearly the same at .
Ardea.
A small V4 ("tipo 100") powered the compact 1939 Ardea. It was a 20° narrow-angle engine displacing just . Bore and stroke were new again at , and output was just at 4600 rpm. For the 1949 "tipo 100B" power was increased to .
Appia.
The V4 returned after the war with the 1953 Appia. It featured an even narrower 10° cylinder bank and just of displacement, fitting below Italy's 1.1-liter tax threshold. An initial of power grew to in 1956. was available in 1959.
Fulvia.
Lancia's final V4 series were used in the Fulvia, remaining in production up until 1976. Designed by Ettore Zaccone Mina, it used a narrow angle (13°) and was mounted well forward at a 45° angle. The engine was a true DOHC design with one camshaft operating all intake valves and another operating all exhaust valves.
Displacement began at just with with a bore and stroke. A higher (9.0:1) compression ratio raised power to soon after.
The engine was bored to to enlarge engine displacement to for the "Coupé" model. This, and some tuning, raised output to , further enhanced up to for the HF model.
The engine was re-engineered with a slightly narrower bank angle and longer stroke for 1967. Three displacements were produced: bore, bore, and bore. The latter engine is most common, with the first unit only sold in Greece. Three levels of performance were available: for common 1.3 Liter (commonly imported in USA and described as "highly tuned" by "Road &amp; Track" at the time); for its 1.3s evolution and for the Rallye HF.
The engine was redone again for a new "HF" with an even narrower 11° cylinder bank and longer stroke for its final incarnation. A bore of gave it a displacement of , and power shot up to between depending on tune.