Chevrolet engineer Ed Cole is credited for being the lead hand in the development of the 265 cid V8 the first in a long line of subsequent engines with a large number of displacements using the same cast iron block mold. From its inception until 1974 the G1 engine was marketed as the Turbo-Fire V8. The first generation (G1) engine line up is unique from the G2, G3, G4 LS, and the G5 (LT/EcoTec3) versions. The 265 was followed in ’57 by a 283 version-this one with either a carburetor or mechanical fuel injection, then a 327, followed by a high performance 350 in ‘67, which was a GM corporate standard engine for many years for all divisions but Saturn even though they all produced their own V8. Then, subsequently, the 350 became both a high performance and a lower output version. By 1970 this original Chevy small block had reach 400 cid The engine was originally known around the tracks as the Mighty mouse motor; later shortened to mouse, the mouse that roared, when the big blocks (the rat motor) came on the scene in 1958. By the time the V8 versions were discontinued in the 1990’s there had been ninety million of this small block produced in the U.S. The V8 engine is still being made in Mexico and sold in a crate form however some of the later generation engines owing their roots to the G1 are still in production for select vehicles and a shortened version is also in American production as a 90 degree V6 as of 2014. This small block engine was rated one of the ten best engines of the twentieth century according to Wards AutoWorld. All the V8 engines produced by Chevrolet up to and including 2014 can trace their roots back to the 265.
The 265’s were first in the 1955 Corvette and Bel Air while at the same time; this “Mighty mouse” engine very quickly became a top choice on the race circuits. The Rochester mechanical fuel injection became an option in 1957 on the slightly bored version, the 283, making it one of the first power plants to produce one horse power for each cubic inch of displacement. This 283 subsequently became the base V8 for all Chevy models. The 327 cu n (5.4 L) is the next step for the G1 block giving this high performance version 1.15 hp per cu in displacement. However the best known and most popular of the small block G1 is the 350 cu in (5.7 L) displacement version. This engine is oversquare with a bore of 4,00 inches and a 3.48 inch stroke (102 mm X 88 mm) which is almost identical to the LS3 engine producing 436 hp (325 kW) today. Most of the LS3 components have changed but this engine is used in every type of passenger vehicle used from sports cars to commercial trucks as well as boats with a highly modified version used in aviation as well. The engine has not been produced in the U.S.A. since 2003 but it remains the most versatile small block engine ever produce. This original 350 is still available as a crate engine from Mexico as either the Mr. Goodwrench brand and for marine or industrial use as the “Vortec”.