​Alfa Romeo Twin Cam Engine

This mid-1960s Alfa Romeo engine was used in midget competition in the Colorado area for several years.  It is a double-overhead cam (DOHC) design and measures 1600cc (98 cubic inches). This engine is fitted with two Weber side-draft carburetors, along with an oil pan out of a 105 GTV.   
​
   The Alfa Romeo Twin Cam engine was introduced in the 1290 cc Giulietta of 1954. The features of the Giulietta engine included:

• Aluminum alloy engine block with cast-iron cylinder liners
• Aluminum alloy cylinder head with hemispherical combustion chambers​
• Forged steel crankshaft running in five main bearings
• Double overhead camshafts driven by a double row timing chain​
• Camshafts directly actuate valves via bucket tappets
• Two inclined valves per cylinder with near central located spark plug
• Inlet and exhaust valves separated by an angle of 80 degrees
• An extremely large, flat, finned oil sump (pan) that kept the engine and oil so cool that in cold weather it was sometimes necessary to block off the radiator airflow to heat the water hot enough for the interior heater to be effective.

​​   This made the Alfa Romeo Twin Cam engine an advanced design for a production car of the mid-1950s. These design features, with minor variations, would form the basis of all future versions of the engine. The capacity was increased to 1570 cc with the introduction of the Giulia in 1962. Racing versions of the Giulia engine include the twin plug engine used in the GTA, which featured a cylinder head with two spark plugs per cylinder.