In the '70s, the American car industry was in the middle of a fierce and highly competitive battle over muscle car supremacy. Straight-line powerhouse vehicles were in high demand among consumers, and every respectable car manufacturer did their best to release high-performance muscle cars to compete with the rest.General Motors was a major heavy hitter at the time, with several successful muscle cars in their multi-brand lineup, such as the Ford Mustang, the Chevelle 454 SS or the Pontiac GTO Judge. The list doesn't end there, however, because Buick also had an ace up its sleeve in what turned out to be one of the most high-performance muscle cars on sale: the Buick Gran Sport 455.For 1970, the Buick Gran Sport 455 was released as the successor to the previous Buick Gran Sport 400, featuring a larger engine and thus, higher performance. Not only was it extremely fast, but it also had the looks to go with it; let's take a look at some of the best features of the Buick Gran Sport 455 from 1970.Related: Everything You Need To Know Before Buying A Muscle Car In 2022

The 1970 Buick Gran Sport 455: Impressive Powertrain And Performance

Blue 1970 Buick GS 455 2dr Convertible
Via Mecum Auctions

The larger engine for the Buick Gran Sport 455 came in the form of a 7.5 liter V8 that was newly made for the 1970 model year. In its base version, the engine was capable of putting out 350 horsepower and 510 pound feet of torque, which were extremely healthy numbers back then. In fact, in terms of torque, the 455 had more torque than any other GM vehicle other than the heavy and low-performance Cadillacs of the time.

Upgrades Turned The Base Gran Sport 455 Into A Beast

Via: Classic Cars

The most notable upgrade offered for the 1970 Buick Gran Sport 455 was the Stage 1 package, named after the stages that refer to rocket ship launches. The Stage 1 version offered a 4-barrel carburetor that helped raise the 455's power output to 360 horsepower, with the torque rating remaining the same. It should be clarified, however, that this horsepower rating was the one provided by Buick and GM themselves, and it is widely believed that the 455 actually had more horsepower than it was given credit for, as several testers confirmed that the actual number was closer to 400 horsepower.

After running the 1/4 mile in just 13.38 seconds at 105.5 mph during testing, MotorTrend magazine declared the 455 stage 1 as the fastest production muscle car they had ever tested. That alone should be enough to illustrate just how prominent the vehicle was.

There was also a stage 2 upgrade offered for the Buick Gran Sport 455, which could be installed at the dealership in the form of a revised camshaft and headers, as well as an intake manifold, push rods and high-compression pistons. Stage 2 versions were rare and supposedly presented many issues, so it isn't really known how many were actually sold like this.

Related: 10 Things To Know Before Buying The 2022 Chevrolet Camaro SS 1LE

A Look At The 1970 Buick Gran Sport 455's Handsome Exterior

1970-Buick-Gran-sport-455-Stage1
via mecum

Even though performance was the most important aspect when it came to the appeal of muscle cars back in the 70s, exterior design was also something to consider for buyers, and manufacturers had to make the effort to stand out with the bodies of their vehicles. Buick truly hit the mark with the Gran Sport 455, which was based on the Skylark.

Up front, the 455 featured a double-circle headlight setup with a split pointed grill in the center. The hood, which also ended with a sort of pointed tip in the middle, featured two hood-scoops to help cool off the vehicle's massive engine. The rear sloped downwards quite aggressively, finishing in a chromed-out rear bumper fitted with slim rectangular rear lights. Chrome inserts were a major feature of the 455s exterior image.

Related: 5 Plymouth Muscle Cars We Wouldn't Touch With A Ten Foot Pole (And 5 Pontiacs)

You Could Transform Your GS 455 Into A GSX For $1,100

1970-Buick-GSX-Stage-1-Cropped-1
Via mecum.com

For the 1970 model year, Buick offered a version of the 455 that was superior even to the stage 1, at least in terms of looks and a few more upgraded parts. For just over a grand above the price of the Gran Sport 455 stage 1, customers could get their hands on the Buick GSX stage 1. This was the most desirable configuration of all when it came to the GS model line, featuring a bi-tone black and white or black and yellow paint job, a beautiful rear wing, and other modified design aspects that made the car look wilder than ever.

In retrospect, the Buick Gran Sport 455 will always hold a place in muscle car history as one of the fastest and craziest of its time, especially the stage 1 version. General Motors took a huge risk when they decided to put so much performance in the body of a Buick, but with perfect execution and even better reception from the public, it's a risk that definitely paid off.