Oldsmobile Aluminum 215
With exception of the small-block Chevy, the all-aluminum Oldsmobile 215 and its Buick cousin are arguably the most prolific American V-8s of all time on the international stage. GM began experimenting with a lightweight aluminum V-8 design in the early '50s for use in Y-body Buicks, Oldsmobiles, and Pontiacs. Buick was given lead R&D responsibilities, but Oldsmobile developed its own unique variant which it introduced in 1961. This new engine platform featured a 3.500-inch bore, a 2.800-inch stroke, and a 4.240-inch bore spacing that contributed to its compact external dimensions. With an aluminum block and heads, the Olds 215 weighed just 320 pounds, making it one of the lightest production V-8s in the world. Many of the 215's trick design elements are still very impressive today, such as shaft-mount rocker arms, a 10.25:1 compression ratio, and the use of six head bolts per cylinder. Despite its modest displacement, the 215 produced 185 hp and 230 lb-ft of torque. However, that was just the beginning. In '62, Oldsmobile strapped a turbocharger to the 215, bumping output to 215 hp and 300 lb-ft. While modern turbo motors employ gasoline direct injection and advanced electronics to successfully combine such high-static compression ratios and boost, the 215 had a different hot rodding trick up its sleeve. To prevent detonation in a carbureted 10.25:1 engine pushing 5 psi of boost, Oldsmobile rigged up a water injection system to cool the intake charge. In the event that the water supply ran dry, a restrictor valve built into the induction tract helped limit boost. By some accounts, the Olds 215 was the first engine to offer a turbocharger from the factory. Unfortunately, the 215 was relatively expensive to produce, and GM opted to replace it with larger, iron-based V-8s throughout the BOP product line.
Even after the demise of the BOP 215 following the '63 model year, the Buick variant lived on overseas. Seeking a lightweight V-8 to use in its small British cars, the Rover Company purchased the tooling and manufacturing rights to the Buick 215 in 1965. Through the decades, Rover sold the revamped Buick 215 to small car builders, and as such, it has appeared in Land Rovers, Morgans, MGs, Triumphs, and TVRs. Furthermore, Mickey Thompson fielded a car powered by a Buick 215 at the '62 Indy 500, which was the first production block-based entry in over 15 years. Believe it or not, the British Brabhams Formula One team took things one step further by converting a destroked version of the 215 for an OHC valvetrain, and winning the championship in the '66 and '67 seasons.
Turbo 3.8L Buick V-6
The Buick V-6 tells a tale more reminiscent of a soap opera script than the documented history of a production engine. This powerplant was conceived from scraps, sold to the highest bidder, dumped in the trash, reacquired by its original owners, and then catapulted to the performance stratosphere. When GM brass decided that the all-aluminum 215 V-8 was too expensive to manufacture in 1962, Buick hacked off two cylinders, cast the block from iron, and created the 198ci Fireball V-6 as a lower-priced alternative. Since this engine retained the 215's 90-degree crankshaft instead of a 120-degree unit that's more common in V-6s, the motor suffered from a rough-running disposition. It was enlarged to 225 ci, and installed in '64-67 Skylarks and '64-67 Cutlasses. Buick then dropped the 225 in favor of Chevy inline-six engines, and sold the tooling to Kaiser-Jeep in 1967. Kaiser was eventually purchased by AMC, and stopped producing the 225 in favor of an AMC straight-six.
Once the oil crisis hit in 1973, GM started looking for more fuel-efficient alternatives to replace its big V-8s. As one possible solution, Buick engineers unearthed an old Fireball V-6 out of the junkyard, installed it in a '74 Apollo, and management was extremely pleased with the results. GM purchased the tooling for the old Fireball V-6 back from AMC, and it re-entered production by '74. The bore was increased to 3.800 inches for '75, which yielded 231 ci (3.8 liters) when paired with a 3.400-inch stroke. Although the 3.8L V-6 was designed more for fuel efficiency than power, Buick made things interesting by bolting a turbocharger to it, then dropping it in the '76 Indy 500 pace car. The turbo V-6-powered Buick Century was a huge hit, and solved the problem created by the prior year's 455-powered pace car, which couldn't accelerate hard enough on the straights.
The success of the pace car prompted Buick to begin installing turbo V-6s across its product line starting in '78. Initially, output was a modest 175 hp, but the introduction of sequential fuel injection boosted power to 200 in '84. The advent of intercooling in '86 increased output to 235 hp, and the '87 model year saw another 10hp increase. Over the years, the turbo V-6 was installed in the Buick Regal, LaSabre, Century, and Riviera, as well as the '80-81 Chevy Monte Carlo and '89 Pontiac Trans Am. By far, the most popular recipient of this powerplant was the Regal Grand National, making it an instant cult classic that could handily smoke V-8 F-bodies of the era. Stout short-blocks allowed cranking up the boost, and running 12-second e.t.'s in near-stock trim. The king of all production turbo Buicks was the '87 GNX, which produced 276 hp and 360 lb-ft of torque. In the running for the wildest nonproduction turbo Buick is the 4.1L V-6 used in the '83 Indy 500 Riviera pace car. Equipped with twin turbos, a forged rotating assembly, six-bolt-per-cylinder head castings and sequential fuel injection, this engine produced 410 hp, exactly twice as much as the Corvette that would be released the following year. As the contemporary new car market has once again started focusing more small-displacement engines using forced induction, the turbo Buick V-6 was clearly ahead of its time.
"...Buick engineers unearthed an old Fireball V-6 out of the junkyard, installed it in a '74 Apollo, and management was extremely pleased with the results."