Complex sentence: Based on the long stroke twin cam which powered earlier Fiat Abarth 131 rally cars, the four valve head was carried over from the 131 Abarth but the original two carburetors were replaced by a single large Weber carburetor in early models and later with fuel injection.
Split into simpler sentences: Based on the long stroke twin cam which powered earlier Fiat Abarth 131 rally cars. The four valve head head was carried over from the 131 Abarth but the original two carburetors were replaced by a single large Weber carburetor in early models and later with fuel injection.