Buick Gran Sport

Buick Gran Sport at a glance

The GS is part of our Buick catalogue and of the golden age in the American muscle car guide.

The Skylark Gran Sport of 1965

Buick's first Gran Sport was a 1965 version of the Skylark. Its V8 was the 401 cu in "Nailhead", which Buick called a 400. It was rated at 242 kW (325 hp) and 603 Nm. Buick sold more than 15,000 that year.

The car set the pattern for the next decade: a Gran Sport was a mid-size Buick with a large V8.

GS 340, GS 350 and GS 400

For 1967 the Gran Sport became a model in its own right, and the GS 400 name was introduced. Its new 400 cu in V8 was rated at 254 kW (340 hp) and 597 Nm. Below it sat the GS 340 with a 340 cu in engine of 194 kW (260 hp) and 495 Nm; fewer than 4,000 of those were sold.

The GS 350 of 1968 used a 350 cu in small-block. In the California GS, the 350-4 engine had 209 kW (280 hp). For 1969 Wikipedia lists 12,465 Gran Sports in total: 4,933 GS 350s and 7,532 GS 400s. The Stage 1 package appeared for the GS 400. Wikipedia lists it at 254 kW (340 hp) in one place and 261 kW (350 hp) in another, both with 597 Nm, and fewer than 1,500 were built.

Road tests of the smaller cars give an idea of their pace. Car Life ran a 1967 California GS through the quarter mile in 16.7 seconds at 81 mph and recorded a top speed of 105 mph. Tom McCahill measured 0–60 mph in 9.5 seconds and 110 mph in a 1969 California GS.

GS 455 and Stage 1

The high point came in 1970. The new 455 cu in V8 of the GS 455 was rated at 261 kW (350 hp) and 691 Nm at 2,800 rpm. The Stage 1 version raised power to 268 kW (360 hp, SAE gross) at 4,600 rpm, with the same torque.

Motor Trend tested a Stage 1 coupé weighing 3,810 lb and recorded a quarter mile in 13.38 seconds at 105.5 mph. Buick sold 9,948 GS 350s and 10,148 two-door GS 455s in 1970.

The GSX

The GSX was introduced in 1970 as the top Gran Sport. It came in only two colours that year: 187 cars in Saturn Yellow and 491 in Apollo White. Of the 678 GSXs built in 1970, 278 had the standard 455 and 400 the Stage 1 engine.

The package continued in smaller numbers: 124 cars in 1971 and only 44 in 1972. With 846 cars in three years, the GSX is the rarest of the Gran Sports. Wikipedia gives no separate net power figures for the 1971–1972 cars.

Century GS (1973–1975)

From 1973 the Gran Sport was based on the Century and sold as the Century GS. Engines were now rated in SAE net. In 1973 the 455 had 186 kW (250 hp) and the Stage 1 201 kW (270 hp); for 1974 the figures fell to 183 kW (245 hp) and 190 kW (255 hp).

Production shrank quickly. In 1973 Buick built 6,637 Century GS cars (4,930 with the 350, 979 with the 455 and 728 with the Stage 1), in 1974 3,355, and in 1975 just 1,288. After that the GS name moved to other Buicks. It returned on the 1986 Century GS with a fuel-injected V6 and on the Regal GS from 1988; a supercharged 3.8-litre Regal GS of 1997–2004 had 179 kW (240 hp).

Gran Sport versions compared

The table shows how quickly the line grew: within six years the line went from 325 to 360 advertised horsepower, and the torque figure grew by almost 90 Nm.

Which GS to look for

The 1970 GS 455 Stage 1 and the GSX are the cars that built the Gran Sport's reputation. The GS 400 of 1967–1969 offers the same idea with a little less power, while the GS 340 and GS 350 are the mild versions. Compare the GS with other mid-size muscle cars of 1970 in our car rankings, and with its corporate cousins such as the Oldsmobile 442 Hurst and the Chevrolet Chevelle SS.

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