The Alfasud Sprint is the coupe version of the Alfasud and was my first Alfa Romeo (KMR766X). It shared the Sud's superb handling and road holding characteristics, but the body was totally new. Designed by Giugaro and released to the press in September 1976 at Baia Domizia, Italy the Alfasud Sprint shared no panels with the Alfasud and this allowed the designer to come up with a much more streamlined shape that has room for four.
The chassis is slightly stiffer than the saloon even though it is a hatchback, this is largely due to the high rear panel and a slight increase in weight. The sprint coupe also always had the most powerful engines available; the original version produced 76 bhp from its 1300 cc engine as opposed to 68 bhp of the Sud Ti. This was achieved using a single twin choke carburettor which was enough to enable the car to top the magic 100 mph mark. Pretty good for a 1300 cc car back in 1976.
The Sprint is a very advanced, designed with careful attention being paid to everything from ride comfort to styling, the flat four engine allowed the use of a very low sleek bonnet line while the cloverleaf emblem in the rear quarter panel is the cabin vent. Technically the Sud Sprint has a large number of features that set it apart from the pack, the engine has a single overhead camshaft and is very over square in design allowing the engine to be revved hard with only modest piston speeds. The camshafts are driven by a toothed belt, a first for Alfa Romeo and being a flat four there are two camshafts. Unlike the alloy cylinder heads, the block is made of cast iron and this is very easily serviced in use as all the engine bearings can be removed without taking the engine out.
The gearbox is fitted onto the rear of the engine and these are both mounted north-south in the chassis the front brake callipers are mounted on two lugs on the gearbox and the disks are secured onto the drive shaft flanges by four securing bolts each side all this helps to reduce the unsprung weight. The unsprung weight is important for ride comfort as when the wheels hit a bump they are forced to move, the mass of the wheel and unsprung items like wheel bearings, etc. force the body to move. The lighter the unsprung mass compared with the sprung mass, the less the sprung mass is forced to move and so the more comfortable the ride. The designer of the Sud, Rudolf Hruska, went to extremes to reduce the unsprung weight and even mounted the shock absorbers up side down.
The rear of the car has a vary simple but ingenious suspension design. There is a dead axle which is located laterally by a phanard rod, while longitudinally it is located by four links; two coming from the front attaching to the bottom of the axle, while the two to the rear attach to the top of the axle. As the axle rises and falls it twists slightly, however if the car rolls, one side twists one way and the other side twists the other way turning the whole axle into a roll bar. The rear brakes are also disks and they are controlled by a load sensitive valve on the body next to the petrol tank. The shock absorbers are also mounted upside down on the rear again to reduce unsprung weight.
As the Alfasud sprint developed, the engine capacity was increased to 1490 cc bringing the power up to 95 bhp and taking the top speed up to 112 mph. This was achieved in the usual Alfa Romeo style by adding two 36mm downdraft carburettors, and just before the Alfasud sprint became the Alfa Sprint the power was increased again, this time without increasing the capacity but by changing the camshaft profile and helping the engine breath better by using a 40 mm carb. The Alfasud sprint changed into the Alfa Romeo Sprint in 1983 when it got a major overhaul getting 33 running gear and it losing its chrome bumpers.