Directly from the official AR Archive Storico site:
YEAR OF PRODUCTION:
Giulia Sprint GTA: 1965-1969
GTA 1300 Junior: 1968 -1973
GT Am 1750-2000: 1970-1971, Am stands for America because it is derived from the USA injection version of the GT 1750
"A victory a day with the everyday car".
Created in 1965, a masterpiece by Bertone, in collaboration with Giugiaro. While it keeps the identical external form of the Giulia Sprint GT, the GTA (Gran Turismo Alleggerita) has a lighter body because of its riveted aluminum paneling and 1600 engine with a new twin-ignition cylinder head. It is particularly suited to sporting customers, given its sparkling performance. From this moment on, the Giulia Sprint GTA wins everything there is to win: Alfa Romeo wins the European Challenge in 1966, 1967 and 1968. Later an engine derived from the 1750 with capacity increased to 2000 is mounted on this model, with indirect injection and twin-ignition. The car is called the GT GTAm, and is capable of developing 220 horse-power and reaching a top speed of 240 Km/hr. Alfa's sporting range is further enhanced in 1969 with the addition of the Junior 1300 Zagato.
Giulia Sprint GTA: 6 cylinders in line, single engine block
GTA 1300 Junior: 4 in line - double ignition
GTAm 1750-2000: 4 in line - double ignition
Giulia Sprint GTA: 1570 cc
GTA 1300 Junior: 1290 cc
GTAm 1750-2000: 1985 cc
Giulia Sprint GTA: 115 bhp at 6000 rpm.
GTA 1300 Junior: 96 bhp at 6000 rpm.
GTAm 1750-2000: 195-220 bhp SAE at 7200 rpm.(1970); 210-240 bhp SAE at 7500 rpm (1971)
Giulia Sprint GTA: over 185 Km/hr
GTA 1300 Junior: 175-210 Km/hr
GTAm 1750-2000: 220-230 Km/hr
Originally Posted by italcarguy
I believe the last GTA Jr. was made in 1975. Can confirm or provide the correct year?