The Buick aluminum V8 was produced for only three model years in its original form, but its impact on the auto industry continued for decades.

 

Today, all-aluminum engines are commonplace throughout the American auto industry. The novelty wore off some years ago. But back in 1961, Buick’s aluminum V8 was a bold innovation for the Motor City. That year, General Motors launched its senior compacts, the Buick Special, Oldsmobile F-85, and Pontiac Tempest. These three products included a number of advanced technical features, and the new 215 cubic-inch lightweight V8 was one of the more noteworthy items.

 

Chief engineer for the new V8 was Buick engine guru Joe Turlay, who had also led the project that created the original Buick Nailhead V8 of 1953. (Read about the Nailhead here.) While the 215 V8 shares no significant features with the Nailhead (or with the 215 CID experimental V8 used in the GM LeSabre) we can see that the new engine was styled, if you will, to resemble the senior Buick V8, especially in the rocker covers (above). In fact, the two Buick V8s are sometimes confused, especially at a distance, but there’s an easy way to tell them apart. On the 1953-66 Nailhead V8 the distributor is at the rear of the engine, while on the aluminum V8, it’s at the front. The 215 shares the familiar GM V8 firing order, 18436572.

 

In many ways, the new Buick V8 was a  fairly typical GM pushrod V8, if a bit more petite than most with a 3.50-in bore, 2.80-in stroke, and 4.24-in bore centers . The real departure was in the materials and construction of the cylinder block, above. A hybrid semi-permanent-mold process was used, in which permanent molds formed the block’s exterior while sand cores created the coolant passages. The aluminum alloy was a special GM recipe, GM 4097-M, containing 11 to 13 percent silicon and around one percent copper, formulated in part to suit the novel casting process.

In another new wrinkle, the eight iron cylinder liners (.1875-in thick centrifugal castings) were cast in place when the block was poured, with serrations on the outside diameters of the liners to help lock them in place (above). The crankshaft main caps were cast iron, too, while the crankshaft was Armasteel—GM’s trade name for its special grade of malleable iron.

 

Naturally, the cylinder heads (interchangeable from left to right) were also semi-permanent-mold aluminum castings with cast-iron inserts for the valve seats and guides, while the intake manifold and timing cover were aluminum as well. When the new V8 was introduced for the 1961 model year, it was sporting a Rochester two-barrel carb and 8.8:1 compression ratio, and it was rated at 155 hp at 4600 rpm and 220 lb-ft of torque at 2400 rpm. At mid-year an optional four-barrel version with 10.25:1 compression was rolled out that boasted 185 hp.

Of course, the truly eye-opening stat of the new V8 was its quoted weight: a mere 318 lbs. That was several hundreds lighter than a small-block Chevy in the same dress, less than many inline four-bangers of the period, and half the weight of a big Chrysler or Cadillac V8. Racers were quick to recognize the performance potential, starting with Mickey Thompson, who successfully ran a modified version in the 1962 Indy 500 with driver Dan Gurney, qualifying in the 8th spot.

 

While Buick and Pontiac used the original Buick version of the aluminum V8, Oldsmobile was allowed to spin off its own 1961-63 variant, above, called the Rockette V8. Its cylinder heads and rocker covers were styled to resemble the big Olds Rocket V8, and it’s interesting to note that while the heads of the Buick and Olds 215 engines look very different, their intake and exhaust manifolds interchange. Additionally, the Olds uses a somewhat different combustion chamber design, and also has an extra row of head bolts along the top of the block on each bank. (The fastener bosses are present in Buick blocks but not drilled and tapped.) Other than that, the Buick and Olds versions are pretty much the same engine, with similar output ratings.  However, the original Rockette V8 had one more distinctive feature, an odd-looking saucepan air cleaner that failed to catch on.

 

The aluminum V8 reached its ultimate production form, arguably, with the turbocharged Oldsmobile Jetfire package of 1962-63 (above). The Jetfire used an AiResearch T5 turbo and an alcohol/water injection system to develop 5 lbs of boost and 215 hp—the magical one horsepower per cubic inch. (See our feature on the Jetfire here.) Nearly 10,000 Jetfires were built before all the 215 aluminum V8s, turbos included, were dropped at the end of 1963.

GM’s first aluminum V8s did get a somewhat mixed reception from American car buyers, due partly to corrosion issues. (Many car owners were still not sold on the merits of permanent antifreeze.) But the engine was dropped when the GM senior compacts were upsized into intermediates for 1964 and the automaker had no further use for a small, lightweight V8. Yet oddly, the story doesn’t end there. Through the twists and turns of automotive history, the engine lived on in various forms for several more decades. For example:

+   When the aluminum V8 was discontinued after 1963, a revised version with a cast-iron block and 300 cubic inches of displacement was introduced for ’64. This V8 was again expanded to 340 CID in 1966 and 350 CID in 1968, and it powered a number of Buicks until it was finally discontinued in 1977.

+   When Buick decided that the compact Special needed a six as well as a V8,  Turlay and staff quickly created a V6 by lopping two cylinders off the aluminum V8 architecture. This 90-degree, cast-iron V6 was introduced for 1962, used by Buick for several years, then acquired by Jeep in 1967. The engine was then brought back to GM in 1975. Continually updated through the years, including in a turbocharged, intercooled version,  the 3800 V6 was used in millions of GM cars before it was finally phased out in 2008.

+   When Formula 1 adopted a 3-liter racing formula for 1966, owner-driver Jack Brabham and Repco of Australia joined forces to produce a single-overhead cam racing engine, the Repco-Brabham 620 V8, using the block from the Olds 215 V8. The unlikely combination won four straight races and the 1966 world title, and from there the Repco-Brabham evolved into a purebred racing engine.

+   The most familiar variant of the Buick aluminum V8 was created in January of 1965, when the Rover Company of Great Britain wrote a check to GM and bought the engine outright (and also picked up as a consultant Joe Turlay, who retired from GM). The former Buick V8 powered various Rover cars and utility vehicles, and as Rover became part of British Leyland, Triumphs and MGs too. Over the next four decades, Rover continually upgraded and enlarged the engine (below) until it ultimately reached 5.0 liters or 305 cubic inches. A 4.0/4.6 liter version of the venerable V8 powered the Land Rover Discovery Series II into the 21st century, until it was finally discontinued in 2004.