was installed between the engine and transaxle in order to relieve stress on the drive shaft and central support bearing. The engine and transaxle were revised to use two chassis attachment points each, rather than the four engine mounts and three transaxle mounts used on earlier cars. As a result, the engine and transaxle were now a rigid unit, flexibly suspended within the chassis by a total of four points. As the engine/transaxle were no longer stressed members, the chassis was slightly softer and noise/vibration issues seen on series I cars were improved. The front bodywork was lowered and lengthened and the front air intake was reduced in size, which improved aerodynamic characteristics and reduced high-speed instability. This was the most visible change between the two series, resulting in the common informal designation of series I cars as "short nose" and series II as "long nose." The rear window was enlarged to improve visibility. In order to improve luggage space, the fuel filler, fuel tanks and spare tyre were relocated and the trunk hinges were changed from internal to externally-mounted. A total of 442 of the 275 GTB road cars were produced between fall 1964 and summer 1966, including 236 Series I "short-nose" and 206 Series II "long-nose" cars. Competition versions From 1964 to 1966, Ferrari developed competition versions of the 275 GTB for use in Grand Touring-class sports car racing. Initial development of a 275 GTB-based racing car was motivated by a specific set of circumstances around Ferrari's racing activities during 1964. The 1962–1963 250 GTO was extremely successful in GT-class racing but was nearing obsolescence in 1964. The 250 GTO's planned successor, the 250 LM, was introduced to the public in November 1963, but the Fédération Internationale de l'Automobile (FIA) refused to homologate it for GT-class racing. In response, Ferrari decided to prepare for the 1964 season by developing in parallel both an updated 250 GTO (called the series II or GTO64) and a competition version of the 275 GTB. Between 1964 and 1966, Ferrari created three distinct series of 275 GTB-based competition cars, the purpose-built 1964/65 275 GTB Competizione Speciale (also known as the 275 GTB/C Speciale), a 1965 group of modified production 275 GTB "customer competition" cars for independent racing teams, and the final development, the purpose-built 1966 275 GTB/C. 275 GTB Competizione Speciale The first racing version of the 275 was the 275 GTB Competizione