The Chevrolet Stovebolt engine is a straight-six engine made in two versions between 1929 and 1962 by the Chevrolet Division of General Motors. It replaced the company's inline-four as their sole engine offering from 1929 through 1954, and was the company's base engine starting in 1955 when it added the small block V8 to the lineup. It was completely phased out in North America by 1962, but GM continued to build it in Brazil until 1979. It was replaced by the Chevrolet Turbo-Thrift engine. First generation: 1929–1936 "A six for the price of a four" The new six-cylinder engine was introduced in 1929 Chevrolet cars and trucks, replacing the company's first inline-4. The 1927 Chevrolet Series AA Capitol had sold very well—over a million units sold as compared to about 400,000 of Ford's Model T—but Ford had introduced a new model in the autumn of 1927: the Model A. The Model A, with its improved four-cylinder, compared much more favourably to the Series AA Capitol, and sales of the Model A surpassed Chevrolet by 1929. Chevrolet had been considering switching to a six-cylinder engine since 1925, and the ascendency of the Model A precipitated the switch. Chevrolet had long been known for its "valve-in-head" design in the previous four-cylinder engine, so General Manager William S. Knudsen and marketing executive Richard Grant insisted that the new six-cylinder design also use overhead valves. The new engine was mockingly called the "Cast-Iron Wonder" and "Stovebolt Six" for its seemingly old-fashioned design, but it was famously advertised as "a six for the price of a four" to great success: the Chevrolet was priced only $100 more than the Model A, and the brand regained the sales lead from Ford in 1931. 194 When introduced in 1929 the six-cylinder was in size and produced . This engine used a forged steel crankshaft with three main bearings and cast-iron pistons. Bore and stroke was . A balanced crankshaft was introduced for 1932, while a higher (5.2:1) compression ratio upped output to . This engine was used in all Chevrolet passenger cars from 1929 through 1932. Applications: 1929 Chevrolet Series AC International - @ 2600 rpm, @ 1000 rpm 1930 Chevrolet Series AD Universal - @ 2600 rpm, @ 900 rpm 1931 Chevrolet Series AE Independence - @ 2600 rpm, @ 800 rpm 1932 Chevrolet Series BA Confederate - @ 3000 rpm, @ 800-2000 rpm 207 The