Volvo Redblock Engine
The Volvo B21 is a slanted straight-four engine first used in the Volvo 200 series, meant to replace the B20. The B21 and all derived engines are often referred to as red block engines for the red paint applied to the block. The primary differences when compared to the B20 was the switch to a SOHC in place of the older pushrod configuration, and an aluminum crossflow cylinder head versus the iron head of the B20. History Initially the overhead camshaft versions were offered as optional equipment on the 240, becoming standard in all markets by the 1976 model year. The overhead camshaft motors were available in displacements of 2.0 (B19 and B200), 2.1 (B21), and eventually 2.3 (B23 and B230) litres. The B21 featured an stroke, and bore. In the US, the B21's power output ranged anywhere between and , based on variations in the compression ratio and was typically supplied with a B or M camshaft. The engines are tilted approximately 15 degrees to right (exhaust side) to make room for the more complicated injection systems. B19 and B21 blocks can be identified by water plugs on one side of the block. The B23 blocks have them on