All Chevrolet engines, whether inline sixes (L6), V6 or V8, are water cooled, overhead valve powerplants. Most of the engines covered by this guide were originally built using cast iron blocks and cylinder heads.
The crankshaft in the inline 6-cylinder engine is supported in seven main bearings, with the thrust being taken by the No. 7 bearing. The camshaft is low in the block and is gear driven. Relatively long pushrods actuate the valve through ball jointed rocker arms.
The small block family of V8 engines, which has included the 267, 283, 305, 307, 327, 350 and 400 cu. in. blocks, have all evolved from the design of the 1955 265 cu. in. V8. It was this engine that introduced the ball joint type rocker arm design which is now used by many car makers. The Chevrolet built 229 and 262 V6s are also similar.
This line of engines features a great deal of interchangeability, and later parts may be utilized on earlier engines for increased reliability and/or performance. For example, in 1968 the 283 was dropped and replace by the 307, which is in effect a 327 crankshaft in a 283 block. And the 267, 305, and 350 V8s all share the same stroke, making crankshaft and bore dimensions, the main difference between the engines.
The 350 V8 diesel is derived from the 350 gasoline engines, except that the cylinder block, crankshaft, main bearings, connecting rods and wrist pins are heavier duty in the diesel (due to the much higher compression ratio). The V8 diesel cylinder heads, intake manifold, ignition and fuel systems are also different from its gasoline engine counterparts. Aircraft-type hydraulic roller valve lifters are used in the diesels.
The Buick built 231 V6 is the only engine used in the midsized Chevrolets which is substantially different. This engine follows Buick V8 practice in that its valve gear incorporates rocker shafts instead of the ball joint style rockers on the other engines.
There are also subtle differences in both the block and cylinder head of the Oldsmobile 307 V8 engine. Although the basic design is similar, these differences from the valve train to the crankshaft make part swapping less feasible than it is within the Chevrolet small block engine family.