Volume IX, Number 3

The History of the Flat or Boxer Engine
(as illustrated by toy cars)
by Henk Hendriks, images by Doug Breithaupt

The original design of the boxer engine dates back to Carl Benz in 1896, as a twin producing 10 HP. During many years to come hardly anyone used the concept until just in between the world wars. The boxer twin was produced for motorcycles like Douglas, BMW, CZ, Harley, Honda and Ural. Just before World War II, the 'people's car' order was issued to Ferdinand Porsche. After NSU and Mercedes Benz made a prototype, this was changed and improved into the KDF, better known as the VW Beetle.

Here is a summary of most car manufacturers who have used a 2, 4, 6, 8 or12 cylinder boxer engines. Basicly they either had air cooled or watercooled designs. Many small-scale diecast models have been produced of cars with boxer engines. Where these exist, examples are shown.

Alfa Romeo

A water cooled flat-4 was used on the Alfa Romeo Alfasud. That engine was later used on the Alfa Romeo Arna (a joint venture with Nissan), the Alfa Romeo 33, the Alfa Romeo Sprint and the Alfa Romeo 145/146. The Alfa 33 TT 12 racecar with an indestructible boxer engine should also be noted.

Alfa Romeo 33 TT - Galgo


BMW used a original motorcycle 2 cylinder in their 600 & 700 car models (600 is a 4 wheel bubblecar) The 700 was a rear, boxer twin engine 'small people's car' which saved the BMW company from being shut down.

BMW Isetta - Kyosho

Chevrolet Corvair

The Chevrolet Corvair was in part a response to the large import of German lowcost air cooled cars for an American people's car. It could come with up to 180 HP if they applied a turbo charged 6 cylinder air cooled power plant, but it was only in production for 10 years.

Chevrolet Corvair - Racing Champions


Citroën used an air cooled flat-2 and a flat-4 in the 2CV. They also used an air-cooled flat-4 on the Ami Super, GS, GSA and Axel models.

Citroën 2CV - Tomica


The DAF was a small people's car from the Netherlands with a unique automatic, the CVT transmission, made use of a boxer engine. The Daffodil model started with a air cooled twin but eventual was replaced with a stronger 4 cyl. line engine.

DAF - Playart


The Ferrari flat 12 boxer engine was first used on their Formula One cars of the late 1960's. The flat 12 engine reached production on the Berlinetta Boxer of 1973 and continued in the Testarossa models through the 1990's.

Ferrari BB512 - Tomica


This Brazilian car builder of mainly off road vehicles used fiberglass bodies with VW mechanicals.


Lancia used a water cooled flat-4 on the high-end Lancia Gamma.

Lancia Gamma -

Kit cars

Citroen based Kit cars include; Le Patron, Lomax, Falcon and several others. VW based Kit cars include; Aztec, Bradley, Kendall, Kelmark, Manx, Porsche Replicas, Puma, RTS and the Wombat or Humbug.

Meyer's Manx - Hot Wheels


Porsche used the VW engine in the early Porsche 356. This engine was replaced by a Porsche designed flat-4 in the late 356s and the 912. The 914 that replaced the 912 was built in partnership with VW using a VW engine.

One of the most famous boxer-engined race cars was the 1970 Porsche 917K. This Le Mans winning car has a 4.5 litre naturally aspirated, air-cooled, flat 12-cylinder engine, delivering 580hp at 8400rpm in a car weighing 800kg.

Porsche 914 - Siku

Porsche 917K - Hot Wheels


This new development by Saab for the 9-6X will be using a Porsche designed Diesel boxer engine in 2006.

Saab 9X Concept - Maisto


Their WRC rally car uses water-cooled front mounted flat-4 engines marketed as H-4, by which they mean 'horizontal' rather than the H cross-section normally meant by 'H' engine.

Subaru WRX WRC - Hot Wheels


This is a Polish car brand with a prototype sports car based on the 101 model with 4-boxer by Wladyslaw Skoczynski.


This east European car brand from Czechoslovakia used several boxer engines in various models. All of them were T number models of which the best known T 600 models and higher used 4 or 8 cylinders.

Tatra - HW (courtesy of Maarten Tys)


VW used air-cooled flat-4s extensively in their early days in the VW Beetle and most early VW designs. VW used a water-cooled flat-4 in the T3 until 1991. The last 200 air cooled T2 bay window buses came off the production line in December 2005 in Brazil.

VW 1200 Beetle - Siku