During this period, myriad changes were made throughout the vehicle beginning with the availability of hydraulic brakes and a folding fabric sunroof in 1950.
 The rear window of the VW Beetle evolved from a divided or "split" oval, to a singular oval.
The change occurred between October 1952 and March 1953.
Beetles built during this time were known as a "Zwitter", or "hybrid", as they used the split-window bodyshell with oval-model chrome trim, vent windows and dashboard.

1953 models received a redesigned instrument panel.
 The one-piece "Pope's Nose" combination license plate/brake light was replaced by a smaller flat-bottomed license plate light.
The brake light function was transferred to new heart-shaped lamps located in the top of the taillight housings.

In 1954, Volkswagen added 2 mm (0.079 in) to the cylinder bore, increasing the displacement from 1,131 (1100) cc to 1,192 (1200) cc.
This coincided with upgrades to various key components including a redesign of the crankshaft.
This increased power from 30 hp (22 kW; 30 PS) to 36 hp (27 kW; 36 PS) and improved the engine's free revving abilities without compromising torque at lower engine speeds.
At the same time, compression ratios were progressively raised as, little by little, the octane ratings of available fuel was raised in major markets during the 1950s and 1960s.

In 1955, the separate brake lights were discontinued and were combined into a new larger taillight housing.
 The traditional VW semaphore turn signals were replaced by conventional flashing directional indicator lamps for North America.

For 1956, the Beetle received what would become one of its more distinctive features, a set of twin chrome tailpipes.
Models for North America gained taller bumper guards and tubular overrider bars.

For 1958, the Beetle received a revised instrument panel, and a larger rectangular rear window replaced the previous oval design.
During this period, myriad changes were made throughout the vehicle beginning with the availability of hydraulic brakes and a folding fabric sunroof in 1950.  The rear window of the VW Beetle evolved from a divided or "split" oval, to a singular oval. The change occurred between October 1952 and March 1953. Beetles built during this time were known as a "Zwitter", or "hybrid", as they used the split-window bodyshell with oval-model chrome trim, vent windows and dashboard.
1953 models received a redesigned instrument panel.  The one-piece "Pope's Nose" combination license plate/brake light was replaced by a smaller flat-bottomed license plate light. The brake light function was transferred to new heart-shaped lamps located in the top of the taillight housings.
In 1954, Volkswagen added 2 mm (0.079 in) to the cylinder bore, increasing the displacement from 1,131 (1100) cc to 1,192 (1200) cc. This coincided with upgrades to various key components including a redesign of the crankshaft. This increased power from 30 hp (22 kW; 30 PS) to 36 hp (27 kW; 36 PS) and improved the engine's free revving abilities without compromising torque at lower engine speeds. At the same time, compression ratios were progressively raised as, little by little, the octane ratings of available fuel was raised in major markets during the 1950s and 1960s.
In 1955, the separate brake lights were discontinued and were combined into a new larger taillight housing.  The traditional VW semaphore turn signals were replaced by conventional flashing directional indicator lamps for North America.
For 1956, the Beetle received what would become one of its more distinctive features, a set of twin chrome tailpipes. Models for North America gained taller bumper guards and tubular overrider bars.
For 1958, the Beetle received a revised instrument panel, and a larger rectangular rear window replaced the previous oval design.
Volkswagen Beetle