SBC 307

A 307 cu in (5 L) version was produced from 1968 through 1973. Engine bore was 3.875 inches (98.4 mm) with a 3.25-inch (82.6 mm) stroke. The 307 replaced the 283 (but are the same engine block with a longer stroke) in Chevrolet cars in 1968 and produced 200 hp (149 kW) SAE gross at 4600 rpm and 300 lb•ft (407 N•m) of torque at 2400 rpm in the 1960s. The later emissions-modified versions produced just 115 hp (86 kW) SAE net, giving the engine one of the lowest power-per-displacement ratings of all time. Chevrolet never produced a high-performance version of this engine, though they did produce, for Outboard Marine Corporation, a high-performance marinized 307, rated at 235 hp (175 kW) and 245 hp (183 kW) SAE gross, depending on year, that shipped with the Corvette/Z-28's cast aluminum valve covers and Rochester QuadraJet carb. Chevy also built other versions of the OMC 307 rated at 210 hp (157 kW), 215 hp (160 kW) and 225 hp (168 kW) SAE gross.