1970 Chevrolet Chevelle SS 454 LS6

This car, Lot 750, sold for $225,500, including buyer’s premium, at Barrett-Jackson’s Houston, TX, auction on October 22, 2022.

With the company’s market share hovering near 50% throughout the 1960s, General Motors executives feared a potential government breakup. This existential threat influenced a number of corporate decisions at the time, including downplaying racing and street performance. This included the edict limiting “intermediates” and Pony cars to engines under 400 cubic inches. For 1970, however, that rule was rescinded.

One and done

With Clean Air Act regulations looming the following year, however, the policy change had a short-lived effect. It did create such unencumbered behemoths as the 455-ci Buick GSX Stage 1, Oldsmobile 442 and Pontiac GTO in 1970. Chevrolet’s top-shelf 427-ci engine received a longer stroke to become the 454. It was available in mild RPO LS5 or wild LS6 versions. The LS6 used solid lifters and forged internals, and made 450 horsepower.

Requiring the Z15 SS 454 option at $503.45, the $263.30 LS6 package with $221.80 M22 4-speed manual added $988.55 to the base Chevelle price of $2,809. All-in, an LS6 Chevelle was pushing $5,000, which was Corvette territory at the time.

In its December 1969 issue, Motor Trend tested such a Chevelle against two other muscle cars, a Plymouth Road Runner 440 Six Pack and a Ford Torino Cobra 429. The Chevy was the clear winner, doing 0–60 mph in 6.0 seconds and running the quarter mile in 13.8, over a half-second better than the others. (Hot Rod got even better results: 13.44 seconds at an amazing 108.17 mph.) The Chevelle delivered more than just straight-line speed, as Motor Trend noted: “Nurtured by the evolution of the Z28, the Chevelles, even the big ones, dart like whippets through the tightest turns. It was certainly the strongest — the most super — of the three.”

Big-block data

Decades ago, Chevrolet lost most of its production data, so definitive numbers for the LS6 Chevelle are lacking. We know from the Tonawanda, NY, engine-plant data that 4,475 LS6 engines were manufactured in 1970; only Chevelles used them that year. (The Corvette got the LS6 in 1971.) But the LS6 was installed in coupes, convertibles and even El Camino pickups, and that breakdown is unknown. Dale McIntosh, who runs the LS6 Showcase & Registry, believes around a dozen convertibles and about the same number of El Caminos received the LS6. Those are obviously the most rare (and valuable). The registry shows a total of 300 of all body styles surviving today.

Built at the Kansas City plant during the last week of April 1970, our subject LS6 was delivered to W. & E. Chevrolet Sales Inc. in Matewan, WV. It was recently restored to its as-assembled condition. The engine compartment shows correct hoses, belts, labels and all other components, including the hand-painted number “19” (the paint code) on the firewall. Underneath, the story is the same, with proper finishes and quality-control paint marks, while the “RU” label on the rear axle indicates a 3.31:1 non-Positraction differential. The pad by the right cylinder head is hand stamped with the last seven characters of the VIN, indicating this is the original engine. Finally, the original trim tag confirms the paint, interior and options. Only a period-correct aftermarket tach and gauge cluster are added, and we can ignore those since they were common “Day Two” additions when new.

The consignor also displayed two original build or broadcast sheets, which would have traveled down the assembly line, informing workers which options belonged on this Chevelle. Build sheets were often thrown away during assembly, but some workers placed them inside the car (at the Kansas City plant this was usually under the front seats, tucked in the springs). With Chevrolets, there is no equivalent to a Ferrari Classiche Red Book or Porsche Certificate of Authenticity, no third-party Marti Report for Fords or PHS Historic Services report for Pontiacs using factory data, so the trim tag and build sheet, when available, are the best we have in validating a Chevy from this era. This LS6 is thus the genuine article, and its quality is likewise breathtaking.

Still ahead of the competition

It’s no surprise given production numbers that an LS6 convertible holds the record for highest Chevelle sale price, at $1,242,000. This is the famous Truppi & Kling NHRA Super Stock champion sold by Barrett-Jackson in 2006 (SCM# 40317). An equally rare LS6 El Camino sold more realistically for $286,000 in January 2022 at Mecum’s Kissimmee, FL, auction (SCM# 6952317).

The more-plentiful LS6 coupes are listed in the 2023 SCM Pocket Price Guide with a value range between $75k–$237k. Prices of the best cars have been rising, and in the past three years LS6 coupes of various quality have sold at auction for $53,350 to $270,000. In general, prices and sales of most vehicles have softened from the frenzy of early 2022. The mega-rich don’t often buy muscle cars, so the same economic headwinds and rising interest rates that the rest of us experience have affected the market. Still, LS6 Chevelles are historically strong right now, ahead of the values of even the vaunted Mopar Hemi B-bodies, the Dodge Charger and Plymouth Road Runner.

The sale price here at $225,500 is near the top of the value range for a #1 condition car, but this is a desirable 4-speed model and in fantastic condition. It would have to be considered well sold, but at an honest, market-correct price. On the block today, just as it did on the street in-period, the Chevelle LS6 continues to outperform its competition. ♦

(Introductory description courtesy of Barrett-Jackson.)