STORY LINE:  SMALL BLOCKS-BIG BLOCKS

So many times we are told descriptions of engines as ‘big block’ or ‘small block’ style, design or type. What really is a small block, big block and what differentiates that nomenclature.

Lawnmowers, log splitters, generators, tanks, boats, ocean going vessels, automobiles … all use fuel fired internal combustion engines, of some type. Engines for vehicle propulsion are typically of the gasoline/diesel variety-piston type and compression or spark plug ignited combustion. Gasoline spark plug fired engines/powerplants garners most of our interests, and that is what we are talking about here, gasoline fired powerplants. The gas engine as we know it, and inventor-inspired by Gottlieb Daimler and Karl Benz in Germany, has been around since the 1800’s, and has progressed from single cylinder magneto fired to; two, four, six, eight, ten, twelve and sixteen cylinder engines that have powered we as Americans, all over this continent-and the rest of the world all over the world. We may not have invented the gasoline engine or the diesel engine, but we sure helped make it “work” for everyone, everywhere.   

Gasoline fired engines in the USA first saw prevalent use by Oldsmobile, as in the Olds Motor Vehicle Company and Olds Motor Works in the late 1890’s. Buick was also a contender in the late 1800’s early 1900’s as the Buick Auto-Vim and Power Company, building gasoline engines for farm and marine use. Ford pioneered his engines/automobiles with the help of the Dodge Brothers and the rest as we might say … is history.

Fast forward a hundred years and this greatness in American history leads us to what we all cherish so much, the engine; big and small as a descriptive.

What makes an engine a ‘Big Block’ vs.  a ‘Small Block’ … basically is it’s family. From the gasoline engines earliest days they were simply … engines, powerplants or motors as some described them. The automobile engine of the ‘30s was Henry’s new ‘Flattie V8’. In 1949 and the early fifties it was the new OHV Oldsmobile, Cadillac and Chrysler HEMI. By 1955 all American auto manufacturers built OHV-V8 engines with Chevrolet becoming the crown prince of volumetric efficiency per pound of steel with the introduction of it’s 265CID-V8.

Most engines up until 1955-discounting the introduction of the Chevrolet-V8, were really big heavy engines as to size and weight, and not until the development of truck engines modified for passenger car use, did the descriptive ‘Big Block’ become common. For the 1958 model year Chevrolet introduced the 348CID ‘W’ engine, Ford the ‘FE’, and Chrysler the ‘RB’, and ‘Big Block’ took hold as a descriptive. During the ‘50s and in the GM ranks-Pontiac, Oldsmobile, Buick and Cadillac all had their own specific design OHV-V8 engines respectively, with almost no deviation as to intra model CID. Ford and Lincoln-Mercury shared CID variations of the venerable Y-block OHV-V8, and Chrysler had the HEMI and polysperical chambered OHV-V8, shared within each division and of varying CID. Only the Plymouth did not use nor share HEMI power until it’s new design resurgence of 1964.

With Chevrolet utilizing only two designs of V8 engines from 1958, it is easy to see how the use of big/small block became a standard descriptive. From 265CID through 400CID and now the GEN III 427 Z06, it is a ‘Small Block’. From 348CID in 1958 to 409 and 427 in 1963, the ‘W’ engine is a ‘Big Block’. The ‘porcupine head’ -so called because of the canted valve design- MK II, MK IV/V engines of 1963 (Mystery Motor) through today, 396/402/427/454/502CID are revered as ‘Big Blocks’.

Ford introduced the ‘FE’ engines in 332/352CID for 1958 and had grown to 428CID before being replaced by the ‘385’ Series 429/460CID engines. These were all ‘Big Blocks’. The 221CID introduced in 1961 and following 289, 302, 351(Windsor/Cleveland) and 400M engines were ‘Small Blocks’. ‘FE’ engines are easily recognized as the intake manifold appears as part of the cylinder head. ‘385 Series’ engines have large valve covers similar to the ‘porcupine head’ Chevrolet 396-502

Chrysler introduced the B/RB engines in 1958 with 350/383CID, 413 in 1959 replacing the original HEMI, and grew to 440CID with variations of ‘B’ series 361/400CID. RB(raised block) represents high deck blocks and are recognized by the flat machined surface next to the distributor ahead of the valley pan on the drivers side top front. All late model HEMI’s are RB. The LA series (new) 318, 340 and 360CID were ‘Small Blocks’.

Buick had variations of CID and did feature a small ‘Nailhead’ V8 and 340/350CID version ‘Small Block’ of the sister 430/455. AMC engines shared block dimensions but had V8s ranging from 304 to 401CID. Pontiac built a 301 as a ‘Small Block’ to the sister 326-455 engine. Oldsmobile built the 260/307/330/350/400CID as a ‘Small Block’ to the sister 400/425/455. 

Big Blocks reigned supreme for the better part of 30 years, 1950-1979 and if you didn’t know, now you may have a better bit of knowledge of what they were. And still are today.

A friend of mine told me of a new tool they carried in the car, to cut seatbelts in case of a rollover mishap. When I asked to see the new tool … they told me it was in the trunk.