• You might be surprised what kind of six cylinder you'll find under that bowtie emblem.corvettes image by michael langley from Fotolia.com
  
  While some enthusiasts might deride Chevy's six-cylinder engines as mere placeholders for a V8, the fact is that some of Chevrolet's most popular models are powered by the venerable and efficient six cylinder. Chevrolet's mainstay for many years were straight (inline) sixes, but V6s became standard equipment when Chevy went "corporate" in the early 1980s. Aside from those standard bearers, Chevy also briefly made one six-cylinder engine that remains a strange footnote in the company's history.
  
  

Straight Sixes

• Contrary to popular belief, Chevy's first six wasn't the much lauded 171-cubic inch "Stovebolt Six" introduced in 1929. Their first attempt at upgrading from the four cylinders common to the early 20th century was the Chevrolet Series C Classic Six (1911 to 1913), one of the very few engines produced while Chevrolet's eponymous founder was still in charge. Chevy's Straight Six line went through five generations before they were phased out of North American production in 1990. Aside from the Stovebolt, perhaps the best known straight six Chevy was the 235-cubic inch Blueflame Six, produced from 1941 to 1954, later produced under license by Toyota (1955 to 1974) as the Toyota "F" Engine. The 136-horsepower Blueflame made its name powering the first of Chevy's Corvettes, which hung onto the powerful and durable engine until it was replaced by a 265-cubic inch V8 in 1955.
  
  

The Flat Six

• In trying to keep up with the sporty set at Porsche, Chevy briefly experimented with a series of air-cooled Flat Six (a.k.a. "boxer" or "horizontally-opposed" engines). These engines came in power levels, stretching from 80 to 180 horsepower (with optional turbocharger). These very particular powerplants were used only in 1960's era "Unsafe at Any Speed" Corvairs, and continue as a popular option for DIY aircraft and airboat builders.
  
  

The V6s

• Beginning in 1978, Chevrolet began manufacturing their line of "90-degree" V6 engines (so-called because their cylinder banks were at a 90-degree angle to each other). Based on the wildly successful small-block, 90-degree V6s gained a reputation for easy maintenance and durability. The only really interesting 90-degree six was the turbocharged 4.3L (a.k.a. "the 3/4 350") used in 1991 Syclones and Typhoons; this bad-boy six produced 280 horsepower and 360 foot-pounds of torque. Since then, GM has used four different V6s to power their Chevys: the 60-degree V6 (produced from 1980 to 2005 in overhead-cam and cam-in-block configurations), the "High Value" V6 (an evolution of the 60-degree, produced from 2004 to the present) and the "High Feature" V6, (2004 to the present), one of three GM V6s to come with an aluminum block and overhead cams.
  
  

The Rotary "6"

• You're probably thinking, "Hey, a rotary (Wankel) engine doesn't have cylinders! And Chevy never made one anyway..." Au contraire. A rotary engine's center rotor is triangular, acting as a set of three revolving combustion chambers when it moves around in the block. Stack two rotor assemblies on top of each other and you've got six combustion chambers total. Chevrolet did just that when it introduced the two-rotor XP-897 GT/two-rotor Corvette Concept car in 1973, which was quickly one-upped by the four-rotor that same year and phased out altogether before either ever saw production.