The 1991 Corvette

The Overview

The 1991 Corvette is the C4’s mid-life facelift, and it was done in the ZR-1’s image. The front fascia was slimmer and smoother with wraparound parking, cornering and fog lamps, the body-side moldings were widened and painted body color, the front-fender gills became four horizontal strakes, the 17 x 9.5-inch wheels took a new turbine, or “saw-blade,” pattern, and the standard coupe and convertible were given the ZR-1’s convex rear fascia with four rectangular taillights, the high-mounted stop lamp set into the fascia above the Corvette script. The ZR-1 kept its unique doors and rear quarters, three inches wider for the 11-inch rear wheels, its roof-mounted stop lamp and its badge, and from twenty feet nobody could tell the difference. Under the skin, the L98 had its last year with new, larger mufflers and a finned power-steering cooler but the same 245 hp (250 with the 3.07:1 axle), the 700-R4 was renamed 4L60, a power-delay circuit kept the radio and windows alive after the key was turned off, a low-oil light joined the driver information center, every car was pre-wired for a cellular phone, and the ZR-1’s “full power” light moved next to its valet key.

The new option was Z07 ($2,155, coupes with the six-speed only): the old Z51 heavy-duty springs, bushings and bars combined with FX3 Selective Ride Control, which gave a car that could be switched between firm and very firm and was meant for showroom-stock racers; 733 were built. The ZR-1 itself was unchanged except for the price, now $31,683 over a $32,455 coupe, or $64,138 before options, and it suffered for it: Chevrolet had planned 4,000 to 8,000 a year, Dodge announced the 400-hp V-10 Viper for 1992 in January 1991, the 1990 buyers who had paid over sticker now had a facelifted base car that looked the same, and ZR-1 sales fell from 3,049 to 2,044. The B2K Callaway Twin Turbo ran out its contract: Callaway built the 500th twin-turbo Corvette on September 26, 1991, badged the cars after it “Callaway 500,” and ended the program after this year with the ZR-1 and a recession against it; the 1991 cars cost $33,000 over sticker, and alongside them Callaway sold the Speedster, a 450-hp open two-seater by Paul Deutschman on the twin-turbo chassis at $107,000 and up, ten of them.

Overall sales fell again to 20,639, coupes outselling convertibles three to one, and inside GM the Corvette’s future was argued over: the all-new car once planned for 1995 slipped toward the end of the decade, and Chevrolet general manager Jim Perkins had to make the case to the corporation that the Corvette should continue at all. He won, and the answer to the Viper and the ZR-1’s price problem was already in the works for 1992, the 300-hp LT1 for every Corvette. Today the 1991 is the quiet one in the middle: the last L98 and the first of the facelifted cars, priced with the 1989–90s, with Z07 coupes and six-speed cars at the top of the standard range, 1991 ZR-1s the second-cheapest LT5 year after 1990, and the Callaway Speedsters and Callaway 500 cars in six figures among the people who collect such things.

The 1991 Corvette Story

With the arrival of the ZR-1 in 1990, the Corvette had once more been elevated to a stature that had been missing since the early seventies. The “King of the Hill” had arrived and had met or exceeded the expectations of most enthusiasts and automobile reviewers alike.

Its arrival had been anticipated for so long that prospective buyers gladly paid well in excess of the $58,995 list price. And yet, as fate would have it, the high priced ZR-1 that was so widely embraced in 1990 would be the same car that would ultimately bring about its own decline beginning just a year later in 1991.

While there was no mistaking the ZR-1’s high-tech approach to mastering triple-digit speeds on command, there were glaring deficiencies elsewhere in the car that adversely impacted the ZR-1’s success in the commercial market place.

Admittedly, despite the hefty $31,683 premium that accompanied the RPO ZR1 package option (note that this was in addition to the already expensive $32,455 base coupe price tag), the ZR-1 was still far more affordable than most exotic European sports cars. The most glaring (and looking back, most obvious) criticism of the ZR-1 was the minimal styling enhancements to the body and interior of the car.

While, by comparison, there was no mistaking a Porsche 911 from a Porsche 944, it took a trained eye to discern the differences between the base coupe and the far more expensive ZR-1.

What made things worse for the 1991 model year was the fact that Chevrolet further blurred the line between the two Corvettes when they introduced some cosmetic enhancements to the 1991 base model coupe and convertible.

While the ZR-1 did retain its unique doors and rear fenders that were required to accommodate the 11-inch-wide rear wheels and tires, the standard coupe and convertible received a ZR-1 inspired rear fascia, with a similar convex styling and four rectangular shaped tail lamps. With this new backend on the base Corvettes, the only distinguishing features of the ZR-1 that remained were the slightly wider rear flanks, the roof-mounted center stop-lamp, and a single badge to distinguish a ZR-1 from a base coupe. In contrast, on 1991 (and beyond) base coupes and convertibles, the third taillight was integrated into the rear fascia just above the CORVETTE emblem.

Another devastating event to adversely impact the ZR-1 line came from outside anything that Chevrolet could readily counteract. In early 1991, Dodge announced that they would be introducing an all-new sports car as part of their 1992 model line – the Dodge Viper.

The Viper would include a 400 horsepower V-10 engine and promised sports car enthusiasts a more expressive way to spend their performance-car dollars. Hailed as “offering some of the most aggressive race-car looks to date”, the Shelby Cobra inspired Dodge Viper would have a dramatically negative impact on the sale of ZR-1’s over the course of the 1991 model year. Where Chevrolet had planned on selling 4000-8000 ZR-1’s per year, total sales of the super Corvette dropped to just 2,044 units in 1991. It appeared that, despite its initial novelty and promise of unsurpassed performance, the ZR-1 had quickly become “yesterday’s news.”

Making matters even worse for GM, it was determined that an all-new Corvette, which had originally been projected for a 1995 arrival, would still be several years away. Due largely to their struggling financial situation, GM’s top brass delayed the program, and the new car would not arrive until 1997. In fact, overall Corvette sales had waned so dramatically that Chevrolet General Manager Jim Perkins was brought before the GM brass to determine whether Chevrolet should continue to produce the Corvette at all. Though ultimately it was agreed that the Corvette would, and should, continue as the division’s flagship, it was also agreed that, until financial conditions improved, Chevrolet would not have the ability to fund the research necessary to develop a mid-engine model, (an endeavor that had been the silent ambition of Corvette designers for generations).

Despite these setbacks, 1991 was not all bad news for the Chevy Corvette. Cosmetically, the C4 Corvette received many additional enhancements to those listed earlier, including a smoother, slimmer front fascia with wraparound parking/cornering/fog lights, wider body-side moldings that were now painted to match the body color, and horizontal front-fender strakes that replaced the previous gill-like louvers.

Additionally, the 9.5 inch wide aluminum wheels were re-designed and now featured a turbine-like appearance.

While the cosmetic makeup of the 1991 Corvette’s interior remained largely unchanged, it did receive a number of mechanical/electrical updates that improved overall operability. A new power-delay feature was added to the audio system and power windows which allowed both to operate after the ignition was switched off until such time as either the driver or passenger doors were opened or for a maximum of fifteen minutes (whichever came first).

Additionally, a “low oil” indicator was added to the driver information center, and all models were pre-wired to accommodate a cellular telephone or other 12-volt accessory. On the ZR-1’s, the “full power” indicator light was relocated to alongside the valet-selection key.

The Corvette’s exhaust system underwent some revisions for 1991. Included in the update were larger muffler sections with a more finely tuned exhaust note and lower back pressure. While the introduction of these new mufflers was intended to add power to the existing L98 engine, the horsepower ratings remained unchanged. In addition to the upgraded exhaust system, a finned power-steering cooler was also installed with the intent of improving performance.

Continuing beneath the car, the suspension package was revamped for 1991 as well. New for the 1991 Corvette was RPO Z07. Priced at $2,155, this option effectively combined the previous Z51 performance handling package with the FX3 selective ride and handling option. It offered prospective owners the option of an all heavy-duty suspension system that drivers could adjust between “firm” and “very firm”. Limited only to Corvette coupes, the Z07 package was intended for true sports car enthusiasts and racers.

The World Challenge racing series was continued in 1991, but Chevrolet no longer offered a specially modified Corvette to run in the series. Instead, consumers would have to purchase a Corvette and perform the modifications themselves.

Did you know? The 1991 model year marked the 10th anniversary of the Chevy Corvette's production at the Bowling Green Corvette Assembly Plant in southern Kentucky.

1991 also marked the final year for the dealer installed Callaway Twin-Turbo package. Much like the ZR-1 option, dwindling sales drove Chevrolet executives to make the decision to discontinue the Callaway option. In fact, fewer than a hundred Callaway Corvettes were sold in 1991 (71 by Callaway’s count, 62 by Chevrolet’s), at an additional $33,000 apiece. Despite the dwindling sales numbers of Callaway Corvettes, Chevrolet did recognize the build of the 500th Callaway Corvette on September 26, 1991. The subsequent Callaway Corvettes that rolled off the assembly line were dubbed “Callaway 500” and could be optioned (for an additional $600.00) with commemorative “Callaway 500” badges.

Notwithstanding Chevrolet’s decision to discontinue the Callaway line as part of Corvette’s RPO (available options package), Reeves Callaway introduced a Corvette conversion kit of his own for the 1991 model year. Dubbed the Callaway Speedster, this open two-seater on the B2K twin-turbo drivetrain produced 450 horsepower and 600 lb-ft of torque. The 1991 Speedster was somewhat reminiscent of the earlier 1988 Corvette Sledgehammer, although its overall appearance was more aerodynamic. The Speedster featured O.Z. brand racing wheels and a Connolly leather interior. Priced at $107,000 (and higher), a total of 10 of these cars were built in 1991.

Production Volumes

Overall, sales of the 1991 Chevy Corvette followed the downward trend started earlier in the model year by the ZR-1. In all, 20,639 units were sold, with coupes outselling convertibles at a ratio of about three-to-one.

With the ZR-1’s sales numbers crumbling around them, and with General Motors unable to fund the development of an all-new Corvette for the foreseeable future, Corvette engineers knew that a happy medium would have to be reached between the performance limited L98 base model and the overly priced ZR-1.

If Corvette was going to retain its stature as a true American sports car against future competitors like the Dodge Viper, there was no question that improvements would have to be made to ensure that every Corvette – not just the super exclusive ZR-1 – would be able to hold its own in the future.