Alfa Romeo Giulia GTA SA
The GTA SA or Souvralimentata (Supercharged) is an amazing car, Autodelta modified the standard GTA 1600 cc and fitted two aircraft cabin blowers, these compressors ran at up to 100,000 rpm and were powered by an oil pump which was mounted on the carb side of the engine above the sump, there was also an additional radiator mounted in front of the coolant radiator in order to cool the supercharger oil. The pressurized air was fed into the air box from a supercharger mounted at either end, there was also a bleed from the air box to the top of the Weber carbs in order to maintain the correct pressure in the float chamber. In order to keep the charge cool, water was injected into the inlet manifold this also had the additional benefit that the GTA SA would run on standard petrol, which was necessary for homologation purposes. The GTA SA's engine was virtually the same as the "standard" GTA corsa, the valve sizes, the bore and stroke and even the compression ratio remained unchanged at 10.5/1.
Homologated as a group 5 car the GTA SA was in competition with the Lotus Cortina and BMW's 2002 range, in order to be competitive the engine was tuned to produced 220 BHP @ 7500 rpm but with huge ammounts of torque. While its weight was up on the standard GTA it still only weighed in at 780 Kg and its top speed was now in the region of 145 mph. After extensive testing at Alfa Romeo's test track at Balocco and Monza the GTA SA first appeared to the public at the 1967 Geneva Motor show and won its first race at Hockenhein in the hands of the German driver Dau. Auto Delta produced 10 GTA SA's but unfortunately the championship regulations changed and in order to be eligible they would have to have produced 1,000 of these rare supercharged cars and there just was not the market for them.