1970 was a big year for General Motors, as the former 400 cubic inch limit was lifted in the midsized cars. “Midsize” was GM-speak for the cars that we today call muscle cars, and once the engineers learned that engine size was no longer a barrier, some pretty spectacular cars rolled out of GM factories in 1970. Chevelle LS6, Oldsmobile Cutlass 442 W30, Pontiac GTO Judge, and the Buick GS 455. They essentially re-wrote the playbook for one short year before looming emissions regulations, insurance prices, and an oil embargo shut down the party. Each car was formidable in its own way, but if you were a grown-up who didn’t need stripes and wanted a little luxury with his performance, the Buick store was the only place you needed to go. The 1970 Buick GS455 was the king of the hill when it came to torque, grunting out 510 pounds of twist that topped even the mighty LS6. Talk about speaking softly but carrying a big stick!

This spectacular numbers-matching Gulfstream Blue 1970 Buick GS455 convertible still delivers an ideal blend of performance and comfort, in fine Buick fashion. It was subject to a very high quality frame-on restoration by a noted GS expert and the results are exceptional. Only 1184 GS 455 convertibles were built in 1970 and of those, only 58 were painted code 25 Gulfstream Blue, making it a rather special find. It’s a deep steely blue, not a light blue metallic and not a turquoise, although we should mention that digital cameras have difficulty capturing colors like this accurately. Our photos are pretty close, but if anything this car looks even better in person. Deep, rich, shiny and finished to better-than-new condition. It wears all its original body panels, including quarters and floors, and given Buick’s notably better build quality, it fits together extremely well. There’s a solid feeling to the doors that a Chevelle or GTO can’t quite match and on the road it feels more supple yet more solid than its lower-priced cousins. The twin nostril hood is, of course functional, but beyond the hood and the racy red stirpes on the rocker trim, the Buick doesn’t really advertise the serious blasting powder that lives underneath. This ragtop also offers show-quality chrome, correct T3 headlights, crisp emblems, and bright lenses that suggest big money was spent on the restoration. We’ve never seen a better A-body convertible.

The code 185 White Pearl interior is a fantastic choice with the Gulfstream Blue. Like Pontiac’s Parchment interiors, it’s off-white with a bit of a pearlescent sheen to the finish that makes it look rich and inviting. Buckets were still optional on the GS, and this car has them, along with a center console with GM’s ultra-cool horseshoe shifter. Other options include power windows and locks, a tilt steering column, a full set of Rally gauges including tach, remote outside mirror, and an AM/FM radio with optional rear speakers. Black carpets and dash keep it from being too bright inside, particularly on warm days, but the light-colored upholstery is ideal for a car that’s going to spend its time out in the sun. The gauges are bright and clear and everything works correctly. All the soft parts were replaced during the restoration, which is only a few years old, and it remains almost as-new with firm seats and no signs of wear or age. Correct rubber Buick-logo mats protect the carpets. Overhead there’s a crisp white power convertible top, which folds easily and stacks neatly, although there is no boot (reproductions are readily available). You will also note the trunk is neatly finished with correct spatter paint and a full-sized spare tire with original protective cover and jack assembly (we have a correct trunk mat on order and it will be included with the car).

When GM lifted the 400 cubic inch limit, Buick engineers immediately set to installing the giant 455 cubic inch V8 that was extensively revamped for performance work in the GS. There’s a nodular iron crank on the bottom, forged rods, aluminum pistons, and deep-breathing heads fed by a Rochester 4-barrel carburetor and that twin snorkel induction system. The cam is a rather mild hydraulic unit that gives the Buick good street manners and an excellent idle, but don’t mistake that for weakness: in 1970, Motor Trend remarked that the factory rating was "some kind of understatement of the year." And yes, the 510 pounds of torque is legit, flinging this middleweight ragtop around like it’s an MG.

This is unquestionably the car’s original, numbers-matching engine with correct partial vin stamped between cylinders 1 and 3, and a proper SR engine code stamped between cylinders 5 and 7. The block carries casting number 1231738 and the carburetor is a correct 7040240 MD Rochester QuadraJet for a Buick GS455 with automatic transmission. The aluminum intake manifold is unique to the GS 455 and even the alternator is a correct 1100774 55-amp unit. The engine was rebuilt during the restoration and runs superbly, starting easily, idling properly, and pulling, well, like there’s 510 pounds of torque yanking it along. It’s also correctly finished with Dante Red engine enamel, a correct dual snorkel air cleaner, and factory-style finishes and fasteners throughout. There might be a few minor signs of use, but you’ll look a long time to find a more carefully finished GS than this.

Sometimes cars are so good that they don’t need frame-off restorations, so don’t look at that as a demerit—it’s really hard to put a car back together as well as the factory did it. Besides, this one shows off 50 years of clean living with no secrets—no patches, no rust, no replacement floors, and if you drive it, well, you don’t have to worry about scratching your undercarriage. That’s kind of liberating. The TH400 3-speed automatic is also matching-numbers, with a matching VIN stamp and a correct BA assembly code. It serves up crisp but not harsh shifts, as you’d expect from a Buick and the TH400 is already legendary as being virtually indestructible, so go have some fun. This car carries 3.42 gears on a Posi limited slip, but that big motor’s torque kind of makes gear ratios irrelevant in the real world—there’s power at just about any speed. You will also find an expensive new Gardner dual exhaust system that exactly replicates the original, rebuilt brakes, steering, and suspension components, and a new gas tank hanging out back. The decode sheet from the GS Historic Society says this car originally came with steel wheels, hubcaps, and whitewalls, but nobody’s going to argue with how awesome those Buick Road Wheels look with fat 245/60/15 BFG radials wrapped around them.

Documentation includes extensive restoration receipts, a lot of spare parts from the restoration (brake parts, pistons, rods, values, camshaft, etc.), and the aforementioned GS Historic Society paperwork.

With only about 600 miles on the restoration, this is a spectacular no-excuses GS 455 convertible. The color is gorgeous, the performance is addictive, and the level of comfort is surprising. It’s a car that does everything right and stands out in a crowd because it’s not a garden-variety Chevelle. If you’re an adult looking for an adult’s muscle car, this Buick delivers in a big way. It also offers a bulletproof pedigree and a good degree of rarity that makes it special. Buicks have long been under-valued in the market, but that seems to be changing—take advantage of this opportunity to own an exceptional GS before the rush. Call today!

Harwood Motors always recommends and welcomes personal or professional inspections of any vehicle in our inventory prior to purchase.