This week’s technical article is about the transverse engine – found in most modern front drive cars and it follows on from a recent article about DKW.
DKW were the first to have a successful transverse engine in a production car. It helped that their engine was a tiny two stroke, two cylinder motor derived from a motorcycle engine. This was in the 1930s and they were very successful – in fact DKW engines went into the first SAAB and other German cars also had transverse mounted engines. So the German market was used to the transverse long before other markets saw it.
It was Alec Issigonis’ Mini that introduced this style of engine mount to the rest of the world. Launched in 1959, it was a revolutionary design all round, with the BMC A Series engine, an 850cc 4 pot motor that was first seen in 1951. Issigonis was poached from Alvis to build a car that would beat the Germans at their own game – with Europe still struggling after the war, the Germans were selling “bubble” or small cars like the DKW. He designed a small shell and then took the 34 hp A Series motor and moved it sideways, then added the transmission to the sump to save space.
Because the engine and gearbox were connected, his team added in an extra gear between the engine and the gearbox to provide a reverse gear. They also put the carburettor at the back of the motor, which helped keep it warm although the distributor was mounted behind the grille and was susceptible to the weather. This produced a front mounted and front drive mini car – hence the name!
The Mini was a huge success and many manufacturers looked at the design to see if they could produce similar designs. FIAT launched the Autobianchi Primula in 1964 with a 1200cc transverse engine. The gearbox was mounted in line with the crankshaft with a differential that was offset and had unequal length drive shafts. This design was adopted by most manufacturers of front drive cars and can be seen on most modern cars.
Some sports cars even mounted their engines transversely, especially when mid mounted. The Toyota MR2 and Spyder as well as high performance machines used transverse engines to reduce the size of the engine/gearbox combination. Volvo used a transverse engine to increase the occupant space inside their vehicles and to provide a larger area to deform in the event of an accident.
With car engines getting smaller, I would expect to see more vehicles using this style of mounting – however, with electric motors being seen as the future, it may not matter where they are mounted.