Volkswagen Beetle - Design Overview

Design Overview

The Beetle featured a rear-located, rear-wheel drive, air-cooled four-cylinder, boxer engine in a two-door bodywork featuring a flat front windscreen, accommodating four passengers and providing luggage storage under the front bonnet and behind the rear seat – and offering a coefficient of drag of 0.41. The bodywork attached with eighteen bolts to its nearly flat chassis which featured a central structural tunnel. Front and rear suspension featured torsion bars along with front stabilizer bar – providing independent suspensions at all wheels. Certain initial features were subsequently revised, including mechanical drum brakes, split-window rear windows, mechanical direction-indicators and the non-synchronized gearbox. Other features, including its distinctive overall shape, endured.

Its engine, transmission, and cylinder heads were constructed of light alloy. An engine oil cooler (located in the engine fan's shroud) ensured optimal engine operating temperature and long engine life, optimized by a thermostat that bypassed the oil cooler when the engine was cold. Later models of the carburetor featured an automatic choke. Engine intake air passed through a metallic filter, while heavier particles were captured by an oil bath. After 1960, steering featured a hydraulic damper that absorbed steering irregularities.

Indicative of the car's utilitarian design, the interior featured painted metal surfaces, a metal dash consolidating instruments in a single, circular binnacle, adjustable front seats, a fold-down rear seat, optional swing-out rear windows, front windows with pivoting vent windows, heating via air-to-air exchange manifolds operating off the engine's heat, and a windshield washer system that eschewed the complexity and cost of an additional electric pump and instead received its pressurization from the car's spare tire (located in the front luggage compartment) which was accordingly overinflated to accommodate the washer function.

Throughout its production, VW marketed the Beetle with a four-speed, manual transmission. From 1961 (and almost exclusively in Europe), VW offered an optional version of the Saxomat semi-automatic transmission — a regular 4-speed manual transaxle coupled to an electromagnetic clutch with a centrifugal clutch used for idle. Subsequently (beginning in 1967 in Europe and 1968 in the United States), VW offered an optional semi-automatic transmission — marketed as Automatic Stick Shift and also called AutoStick) — which was a 3-speed manual coupled to an electromatic clutch and torque converter.

While the overall appearance of the Beetle changed little over its life span, it received over 78,000 incremental changes during its production.