High Quality Content by WIKIPEDIA articles! Alfa Romeo Twin Spark (TS) technology was used first time in Alfa Romeo Grand Prix car in 1914. In the early 1960s it was used their race cars (GTA, TZ) to enable it to achieve a higher power output from its engines. And in the early and middle 1980s, Alfa Romeo incorporated this technology into their road cars to enhance their performance and to comply with stricter emission controls. Twin Spark name usually refers to the engines installed in Alfa Romeo cars. Initially appearing in Alfa Romeo 75 model and then used in Alfa Romeo 164, 155, 145, 146, 156, 147, 166 models. The TS series engines are all '4 cylinder inline' with twin cam (DOHC) shafts. The original 8 valve engine featured a light alloy (Si enhanced alu alloy) block + head, wet cooled iron cylinder liners and the camshafts were driven by double row timing chains (long and short). Similar design to the earlier and famous Alfa Romeo DOHC engines, but with narrower valve angle on this model. The later 16 valve engines had a heavier cast iron block engine, with an alloy head, and the camshafts were belt driven.