1973 Chevrolet Corvette 454/275

This car, Lot 377, sold for $44,000, including buyer’s premium, at Barrett-Jackson’s Las Vegas auction on September 28, 2018. It was offered with no reserve

More power

Oscar Wilde wrote, “Nothing succeeds like excess.” Most car people want the biggest optional motor, and some of us prize the engine call-outs and badging as much as the performance they promise. To collectors and drivers alike, there is an undeniable appeal to owning the top of the line.

The Corvette, already a fine performer and capable racer with many variations of the ubiquitous small-block Chevy, welcomed its first “big block” in 1965. The L72 with 396 cubic inches was rated at 425 hp — a whopping 70% increase in power over the base engine. The following year, the 427 was introduced, and until its retirement in 1969, it provided the basis for an array of high-performance options that were rated up to 435 horsepower.

For 1970, the ultimate big-block, the 454, appeared. Initially offered as the 390-hp LS5, it was augmented in ’71 only by the 425-hp LS6. Beginning in 1972, horsepower numbers dropped to 270 due to the switch to net horsepower ratings and the implementation of some emissions regulations.

A year of change

Until 1973, the growing list of government safety and environmental mandates to the C3 were largely invisible.

As the C3 entered its sixth year, the chrome front bumper disappeared, replaced by a new body-colored urethane nose. Adding 35 pounds of weight, it met new government requirements for low-speed impact protection. However, the chrome twin-blade bumpers remained in back, giving the car, in the eyes of many, a less-than-integrated look.

Additionally, side-impact beams were added to the doors, and a new coolant recovery system, air-induction hood and radial tires were added. And pointing the way to the C3’s future as more of a cruiser than sports car, increased sound deadening materials and quieter mufflers were added.

Nearly 15% of production was fitted with the new LS4 big-block. A revised version of the LS5, the new engine had a milder cam and improved emissions, yet at 275 hp, it was rated slightly higher than the earlier motor. Torque rating stayed at 390 foot-pounds.

The big block provided respectable performance. Road & Track found it could reach 60 in 7.2 seconds and run a quarter mile in 15.4. Car and Driver tested a 4-speed and knocked almost a second off that. Oddly, at $250, the big-block was less expensive than the small-block L82 350/285 engine priced at $299. In its review, Car and Driver said it preferred the small-block car, saying it had better balance, while conceding that many, including Corvette engineers, liked the torque provided by the larger engine.

Our subject car is a well-equipped example, featuring the LS4, 4-speed and a/c. It wears very period Elkhart Green paint, which has a nice shine and shows no damage. It rides on the standard factory Rally wheels, and wears raised white-letter tires, introduced mid-year to supplement narrow whitewalls.

The interior is basic black and looks to be in good shape, with minor wear to seat fabric, carpets and steering column. An aftermarket pad is atop the parking-brake housing, which serves as the center armrest. The engine compartment is clean and stock, with factory decals in place and just the usual corrosion on the brake-fluid reservoir. The auction company description doesn’t indicate if, or when, any restoration or refinishing was done.

Decline into the disco era

The C3 went through several phases during its long (many would say too long) 1968–82 production run. 1968–72 cars are considered the most sporting of the bunch. These are the least affected by regulations, and were out the door before the energy crisis. That, along with further emissions requirements, played havoc with the remainder of the C3’s run.

The ’73s and ’74s might be characterized as mid-period C3s, having some government-mandated changes, but still respectable performance. A matching plastic rear bumper arrived and the big-block departed in ’74, as did the convertible the next year.

The final years of the C3 were more disco-era than muscle-car-era, with smog-strangled engines burdening the aging design. As power decreased, GM increasingly made features such as a/c, power windows, telescopic steering wheels and AM/FM radios standard, turning the Corvette into a luxury car with sporting pretentions.

Fair price for a big-block

At $44k, this car was well sold compared with the recently restored, numbers-matching, 4-speed 350/300 1969 Corvette that sold for $23,100 at Barrett-Jackson’s Connecticut June sale (profiled in ACC #41).

The differential is increased when you consider that car’s condition and the fact that it’s a more desirable chrome-bumper car. Of course, what that car lacked was the bragging rights awarded to those who possess a car with the largest available engine.

This ’73 is a nice car, but one year too new to be seated at the chrome-bumper cool-kids table. The ACC Pocket Price Guide median for a big-block is $25,500 — a small premium over the L82 small-blocks, but a sizeable jump over the base-engine car ($16k), indicating that this was exceptionally well sold.

Searching the ACC Premium Auction Database, two big-block ’73s were sold by Mecum this year. One went for $22,500 at their Los Angeles sale in February (ACC# 6877899), while another brought $63,800 at Monterey in August (ACC# 6865324). This sale splits that difference.

While $44,000 no doubt seems excessive for any rubber-bumper car, it helps to have to look at this sale from a “glass half-full” perspective.

The top engine option/big-block versions of any muscle or pony car carry a premium, and the last two cars I profiled for ACC suggest this price may not be as high as it seems. A middling-quality ’70 440 Road Runner profiled in ACC# 41 brought the same amount, while a recently restored ’69 Nova SS 396 sold for $58,300 (ACC# 40). And although there are some exceptions, a quick look through the price guide indicates you’ll pay comparable money for many ’69–71 Chevelle SS 396/454s , ’69–71 Camaro Z/28s, some Nova SSs, any 440-powered Mopar, and most Mustang Mach 1/428s.

Finally, as derided as they are, the middle-age C3s are still Corvettes, and they have an undeniable cachet. That this (albeit half) plastic-bumper car brought comparable money to ’71–72 chrome-bumper 454s indicates the increasing acceptance of later Corvettes.

I suspect buyers who are too young to remember the media catcalls during the C3’s 190-hp twilight years just see these cars as affordable but stylish collectibles, ignoring their performance limitations.

So when it comes to big-block Corvettes, even the relatively unloved ’73–74 plastic-bumper cars, the price paid here just might be the market. As with many of his quips, Mr. Wilde proved himself a keen observer of the human condition, or in this case, collector-car market.

(Introductory description courtesy of Barrett-Jackson.)