Joined: 14 Aug 2006
|Posted: Mon Jun 08, 2015 11:32 am Post subject: The versatile Buick 215 engine - sold in haste by GM ???
|The versatile Buick 215 engine.....was it sold to British Leyland in haste by General Motors
General Motors experimented with aluminum engines starting in the early 1950s. The Alcoa (Aluminum Company of America) was pushing all automakers to use more aluminum. An early-development supercharged version of the 215-cubic-inch (3.5 L) V8 was used in the 1951 Le Sabre concept car and the 1953 Buick Roadmaster concept car, and work on a production unit commenced in 1956.
Originally intended for 180-cubic-inch (2.9 L) displacement, Buick was designated by GM as the engine design leader, and decided to begin with a larger, 215-cubic-inch (3.5 L) size, which was deemed ideal for the new "senior compact cars" introduced for the 1961 model year. This group of cars was commonly referred to as the "B-O-P" group — for Buick-Olds-Pontiac — or the Y-bodies.
Known variously as the Fireball and Skylark by Buick (and as Rockette, Cutlass, and Turbo-Rocket by Oldsmobile), the 215 had a 4.24 in (108 mm) bore spacing, a bore of 3.5 in (89 mm), and a stroke of 2.8 in (71 mm), for an actual displacement of 215.5 cu in (3,531 cc).
At the time the engine was the lightest mass-production V8 in the world, with a dry weight of only 318 lb (144 kg). Measuring 28 in (71 cm) long, 26 in (66 cm) wide, and 27 in (69 cm) high (same as the small-block Chevy), it became standard equipment in the 1961 Buick Special.
Oldsmobile and Pontiac each used an all-aluminum 215 on its mid-sized cars, the Oldsmobile F-85, Cutlass and Jetfire, and Pontiac Tempest and LeMans. Pontiac used the Buick version of the 215; Oldsmobile had its own.
The Oldsmobile version of this engine, although sharing the same basic architecture, had cylinder heads and angled valve covers designed by Oldsmobile engineers to look like a traditional Olds V8 and was produced on a separate assembly line. Among the differences between the Oldsmobile from the Buick versions, it was somewhat heavier, at 350 lb (160 kg).
The major design differences were in the cylinder heads: Buick used a 5-bolt pattern around each cylinder where Oldsmobile used a 6-bolt pattern. The 6th bolt was added to the intake manifold side of the head, one extra bolt for each cylinder, meant to alleviate a head-warping problem on high-compression versions. This meant that Oldsmobile heads would fit on Buick blocks, but not vice versa.
Changing the compression ratio on an Oldsmobile 215 required changing the heads, but on a Buick 215, only the pistons, which was less expensive and simpler. For that reason, the more common Buick version (which looks like a traditional Buick vertical valve cover 'nailhead' V has today also emerged as more desirable to some. But the Olds wedge-shaped/quench combustion chambers/pistons are more compatible with modern low-octane/low-lead motor fuels than the Buick 'hemisperical'-shaped combustion chambers and domed pistons. Later Rover versions of the aluminum block and subsequent Buick iron small blocks (300 with aluminum, then iron heads, 340 and 350 with iron heads) went to a 4-bolt-per-cylinder pattern.
At introduction, Buick's 215 was rated 150 hp (110 kW) at 4400 rpm. This was raised soon after introduction to 155 hp (116 kW) at 4600 rpm. 220 lb·ft (298 N·m) of torque was produced at 2400 rpm with a Rochester 2GC (DualJet) two-barrel carburetor and 8.8:1 compression ratio. A mid-year introduction was the Buick Special Skylark version, which had 10.00:1 compression and a four-barrel carburetor, raising output to 185 hp (138 kW) at 4800 rpm and 230 lb·ft (312 N·m) at 2800 rpm.
For 1962, the four-barrel engine increased the compression ratio to 10.25:1, raising it to 190 hp (140 kW) at 4800 rpm and 235 lb·ft (319 N·m) at 3000 rpm. The two-barrel engine was unchanged. For 1963, the four-barrel was bumped to 11:1 compression and an even 200 hp (150 kW) at 5000 rpm and 240 lb·ft (325 N·m) at 3200 rpm, a respectable 0.93 hp/cu in (56.6 hp/L).
Unfortunately, the great expense of the aluminum engine led to its cancellation after the 1963 model year. The engine had an abnormally high scrap ratio due to hidden block-casting porosity problems, which caused serious oil leaks. Another problem was clogged radiators from antifreeze mixtures incompatible with aluminum. It was said that one of the major problems was because the factory had to make extensive use of air gauging to check for casting leaks during the manufacturing process and was unable to detect leaks on blocks that were as much as 95% complete. This raised the cost of complete engines to more than that of a comparable all cast-iron engine. Casting-sealing technology was not advanced enough at that time to prevent the high scrap rates.
The Buick 215's very high power-to-weight ratio made it immediately interesting for automotive and marine racing. Mickey Thompson entered a stock-block Buick 215-powered car in the 1962 Indianapolis 500. From 1946-1962, there had not been a single stock-block car in this race series.
In 1962, the Buick 215 was the only non-Offenhauser powered entry in the field of 33 cars. Rookie driver Dan Gurney qualified eighth and raced well for 92 laps before retiring with transmission problems.
Surplus engine blocks of the Oldsmobile (6-bolt-per-cylinder) version of this engine formed the basis of the Australian Formula One Repco V8 used by JAck Brabham to win the 1966 Formula One world championship. No other American stock-block engine has won a Formula One championship.
Rights to these engines were purchased by the British Rover Company and used in the 1967 Rover P5B that replaced the 3 L straight six Rover engined P5. Throughout the years, the Rover Co., which became part of British Leyland in 1968, and its successor companies constantly improved the engine making it much stronger and reliable.
Capacities ranged from 3.5-5.0 L (215 to 307 in³). This engine was used for V8 versions of the MGB-GT known as the MGB GTV8. This came straight from the MG works at Abingdon-on-the-Thames. Rover also used the engine in the 1970 Range Rover which saw the engine successfully returning to the USA after the Range Rover's 1986 introduction.
American Buick 215s have also been engine swapped into countless other platforms, especially Chevrolet Vegas and later British cars MG sports cars including the MG RV8 in the 1990s, Triumph TR8, and various sports sedans and sports cars by the MG Rover Group and specialist manufacturers such as TVR and the Morgan Motor Company.
The engine remains well-supported by enthusiast clubs, specialist parts suppliers, and by shops that specialize in conversions and tuning.
The 215 was also used in the Italian-American gran turismo Apollo in 1962-1963, as well as in the Asardo 3500 GM-S show car.
Although dropped by GM in 1963, the Rover V8 engine remained in production use for more than another 39 years, even longer on the aftermarket. GM tried to buy it back later on, but Rover declined, instead offering to sell engines back to GM. GM refused this offer.
In the mid-1980s, hot rodders discovered the 215 could be stretched to as much as 305 cu in (5 l), using the Buick 300 crankshaft, new cylinder sleeves, and an assortment of non-Buick parts. It could also be fitted with high-compression cylinder heads from the Morgan Plus 8. Using the 5 liter Rover block and crankshaft, a maximum displacement of 317.8 cu in (5,208 cc) is theoretically possible.