1991 Corvette guide: the ZR-1's tail on every car, the last L98, Z07 and 2026 prices

Chevrolet’s ordering information put the body first: a new front fascia “with wraparound park/turn/fog lamps,” the ZR-1-style rear with its new taillamps, body-color side moldings, new gill panels behind the front wheels, new wheels and the high-mounted stop lamp moved into the rear fascia. The car grew with the new ends: 178.6 in, up from 176.5 in, on the same 96.2 in wheelbase (order guide).

The rest of the list is shorter and mostly electrical:

• Wheels. Still 17 x 9.5 in with P275/40ZR17 Goodyear Eagles, in a new “lightweight” design often called the saw-blade wheel, on a 4.75 in bolt circle with M12 x 1.5 nuts (MVMA sheet).
• A low oil level indicator, worked by a float in the oil pan.
• The Delayed Accessory Bus. The power windows and the stereo keep working for 15 minutes after the key comes out, until the driver’s door opens. GM bulletin 91-115-8B calls it a feature and tells dealers “No attempt should be made to override this system.”
• Smaller things. A 12-volt accessory power wire, an expanded AM band, larger mufflers with less back pressure, Bosch ABS IIS and lit vanity mirrors on both visors.
• A different airbag system (see A different airbag, and a quieter complaint file).

What stayed. The interior is the 1990’s: the hybrid cluster, a liquid-crystal speedometer beside analog gauges; the leather-wrapped airbag wheel; the glove box; and the 1990’s gray-black buttons, which turned all black for 1992. Seats were cloth as standard, with leather buckets or adjustable leather sport seats optional (GM). Owners in a 2003 CorvetteForum thread call it the same car as a 1990 under the skin, apart from the nose and tail.

What came next. For 1992 the 300 hp LT1 replaced the L98, 50 hp stronger than the best 1991, with traction control standard, two rectangular exhaust tips in place of four round ones and all-black dash buttons. The 178.6 in body carried over.

How much horsepower does a 1991 Corvette have? GM rated the L98 at 245 hp, or 250 hp with the six-speed or the 3.07 axle. The L98 is a 5.7-liter (350 cu in) pushrod V8 with aluminum heads, Tuned-Port Injection and roller lifters. GM’s MVMA specification sheets list its power teams (page 17):

Two things changed from 1990. The six-speed’s axle went from 3.33 to 3.45, and the six-speed convertible became a 250 hp car; every 1990 convertible was rated 245.

G92, and why a 250 hp automatic coupe has more than an axle. G92, the performance axle for automatics, cost $50 and wasn’t offered with the six-speed. On the coupe, GM’s order guide also required the KC4 engine oil cooler and either FX3 or Z07. So a 250 hp automatic coupe also has the oil cooler and adjustable shocks. The six-speed, a no-charge option, required KC4 too.

Gearboxes. The four-speed automatic (GM’s 4L60, also called the THM 700-R4) had ratios of 3.06, 1.63, 1.00 and 0.70. The ZF six-speed ran 2.68, 1.80, 1.31, 1.00, 0.75 and 0.50, with a dual-mass flywheel. The 1989 guide explains the computer that skips gears at light throttle and the low-speed growl that Chevrolet’s 1989–1991 exchange bulletin, 91-89-7B, called normal.

1991 Corvette specs, from GM’s order guide and MVMA sheets:

How fast is a 1991 Corvette? GM’s 1991 kit gives no 0–60 time or top speed, and no 1991 road test turned up for this guide. The Car and Driver test filed online under a 1991 title is from the February 1990 issue and prices the 1990 coupe. The 1990 guide has period figures for 1990 cars, which share the L98 but not the 1991 six-speed’s 3.45 axle.

The 1990’s Z51 handling package left the order sheet, and a new code took its place. Chevrolet’s order guide aimed Z07, the “Adjustable Performance Handling Package,” at the “Gymkhana/Autocross Enthusiast.” The tally: $2,155, coupes only, 733 built. That count is Corvette Action Center’s and Hagerty’s; no GM document read for this guide gives one.

GM’s MVMA sheets show what the money bought against a base coupe:

• Shocks. FX3’s Bilstein Selective Ride Control, adjusted from the console, with a performance calibration.
• Springs and bars. A rear spring rate of 330 lb/in against 233; a 30 mm front bar against 26 mm, and a 26 mm rear bar against 24 mm.
• Brakes. J55 heavy-duty brakes: 12.9 in front rotors, 28 mm thick, against 11.9 in and 20 mm (page 36).
• Coolers. The engine oil cooler and a heavy-duty power steering cooler, all for 9.5 lb, GM’s weight page says. With the automatic, Z07 required the G92 axle.

Corvette Action Center’s 1991 page calls the ride “firm to very firm.” A technical writer on its forum adds that 1991 was the only L98 year of Z07, and the only Z07 year with the oil cooler included. How many Z07s were automatics isn’t settled. FX3 alone, the adjustable shocks without the springs and brakes, cost $1,695 on either body. The February 1991 order guide ties J55 to Z07, so a convertible with J55 on its label needs explaining.

Spotting a real one. GM never put a Z07 badge on a Corvette. In a Corvette Action Center thread (opens in new tab), the owner of a badged 1991 automatic found FE1, the base suspension code, on his option label and no FX3. A real one shows Z07, FX3 and J55 on the label, an FX3 knob on the console and the bigger rotors.

Prices. Chevrolet’s order guide, revised February 25, 1991, lists the coupe at $33,005 and the convertible at $39,320 with destination; Corvette Action Center and Hagerty give $32,455 and $38,770 before it, a $550 difference on both. Before destination, that’s $476 more than a 1990 coupe and $1,506 more for the convertible (this site’s arithmetic).

Production. GM’s July 1992 production release (1992 kit, page 101) prints 14,967 coupes and 5,672 convertibles, 20,639 in all, and notes that the coupes include 2,044 ZR-1s. That’s 3,007 fewer than 1990’s 23,646, and the C4 guide’s table credits GM for the same figures.

Options. The $1,333 preferred equipment group 1 added electronic air conditioning, a Delco-Bose stereo and a power driver’s seat. Prices below are GM’s February 1991 order guide’s; counts are Corvette Action Center’s, as printed, ZR-1s possibly included:

Bose stereos went in 19,131 cars, 15,345 with the CD player. Corvette Action Center prints lower prices on seven lines (AQ9 $1,050, leather buckets $425 against GM’s $475, each power seat $290, the roof panels $615, C2L $915, C68 $180, G92 $22). Four of them match 1990’s prices, which hints at a start-of-year list; no GM copy of one turned up.

Colors. Ten, with Corvette Action Center’s counts (they total 20,634, five short of production):

The yellow is GM’s “Yellow, Corvette,” code 35, not the 1990’s Competition Yellow, code 53, which Chevrolet stopped in May 1990 because it shifted color in the sun (1990 guide). Turquoise Metallic ran 1990–1991 only; the 1992 list has none.

Interiors and tops. Cloth seats went in only 484 cars (379 black, 105 saddle). Black leather led at 10,376, then red 4,481, saddle 3,084, gray 1,889 and blue 809 (Corvette Action Center’s trim counts overshoot production, so treat them as rough). Convertible tops came in white, black, saddle and, new for 1991, blue, on just 162 cars.

The ZR-1 package, RPO ZR1, added $31,683 to the coupe for a $64,138 car before destination, and 2,044 were built, the second-highest total of its six years. It kept the 375 hp LT5, a four-cam, 32-valve V8, with the six-speed and the 3.45 axle. For 1991 it gave up its exclusive tail to every other Corvette, and GM didn’t add “ZR-1” emblems above its gills until 1992. On a 1991, the ZR-1 tells are the stop lamp on the hatch glass, the wider rear over 17 x 11 in wheels, and Z fifth and J eighth in the VIN. The C4 ZR-1 buyer’s guide covers the LT5, its service record and how to buy one.

The Callaway. RPO B2K, the Callaway Twin-Turbo, stayed a dealer-ordered option for its last year: 62 cars at $33,000 by Corvette Action Center’s count, 63 by Hagerty’s. The 1987 guide explains how B2K cars were built. Hagerty’s February 2026 #3 values put a 1991 Callaway at $29,400 as a coupe and $34,300 as a convertible, close to three times a stock car. Without paperwork, a “Callaway” is just a modified Corvette.

The driver airbag was in its second year, but not its second year of the same system. GM bulletin 91-107-9, as Corvette Action Center reproduces it (opens in new tab), told technicians in October 1990 that the 1991 Corvette’s Supplemental Inflatable Restraint (SIR) system “is different from the 1990 system,” and closer to the Camaro’s and the Caprice’s:

• At key-on, the INFL REST lamp flashes seven to nine times and goes out. A 1990’s stays lit about five seconds.
• The 1991 keeps current and history codes and turns the lamp off when a fault clears; a 1990 holds every code until a technician clears it.
• On a 1991, the FASTEN SEAT BELT lamp doesn’t come on for an airbag fault.

The 1990’s fault, corroded crash sensor mounts on the frame rails, stayed with the 1990. Bulletin 90-436-9J says the condition and its repair “apply only to 1990 Corvette,” and that 1991 and later cars don’t set the codes for it. The 1990 guide covers that fault. On a 1991, a lamp that stays lit means a current fault: have the codes read and the system repaired, never disabled.

NHTSA’s file. It starts in September 1994, so nothing from when these cars were new is in it. The 1991’s 24 complaints (opens in new tab) were filed from March 1995 to July 2021. By this site’s reading:

• Seat belts, 8: belts locked or jammed, several with recall parts unavailable.
• Brakes, 3, plus one crash filed twice: a caliper that came off, a punctured ABS hose, a brake line eaten by battery acid; the crash report, one owner’s account, describes sudden acceleration and failed brakes.
• Electrical, 4: a car that burned with no cause given, two alternator filings that look like one car, and an odometer dispute.
• Audio, 3: Bose amplifiers that popped, hissed or smoked, and a dead CD player.
• The rest: rear wheels that seized, one airbag module, two aftermarket tire complaints.

One airbag complaint, against 18 of the 1990’s 34. Nothing describes the dash, the ZF gearbox or cooling, and no 1991 has the LT1’s troublesome Opti-Spark distributor.

One recall. NHTSA’s recall list (opens in new tab) holds a single GM campaign for the 1991: 91V143000, front seat belts on 1984–1991 Corvettes that can lock up or jam in the retractor. GM ran it as campaigns 91C25 (left) and 91C26 (right), replacing only belts that had already locked or jammed, and the 1991 is the last year it covers. The C4 guide covers the stickers and owners’ trouble getting the repair now. A jammed belt is a safety defect to fix.

GM’s 1991 bulletins survive in Corvette Action Center’s transcriptions (NHTSA’s index starts in 1995). The ones that are the 1991’s own:

• Fascia paint. Some 1991s built before VIN M5103213 may have paint peeling on the front bumper fascia, bulletin 91-134-10 (opens in new tab) says; GM supplied replacement fascias in body color. That’s roughly the first 3,200 cars.
• The ABS pump and light (91-491A-5). If voltage dips below 9.4 V while cranking, the ABS self-test reruns five minutes later, so the pump buzzes and the ABS Active light flashes on the road. A revised control module (GM 10223326, OEM) cuts the wait to five seconds.
• Climate control (91-200-1A). On cars with electronic climate control, the air mix door can stick full hot or full cold, with code 01 or 02 in the control head; a revised programmer is the fix when normal diagnosis fails.
• Starter on automatics (92-322-6D). A purple wire from the park/neutral switch rubs on the shift bracket and starves the starter: a click or nothing. GM says the condition “existed from start of production in 1991, to VIN N5107500 in 1992.” Unlike a PASS-Key fault, it sets no codes. Paint on the starter flange can break its ground too (91-231-6D).
• Odds and ends. Fuel starvation at cold start (92-227-6E), an underhood lamp fuse shipped on a card for the dealer to fit (91-116-8C), and dash and roof rattles (91-264-10).

Shared with earlier years: the engine harness rubbed through by the clamp below the oil pressure sensor (91-337-6D), radio faults (91-229A-9A), the automatic’s coast-down clunk (91-372-7A), a fluttering oil pressure gauge (91-451A-8C), slow reverse below 0°F (91-493-7A) and blue smoke at start-up from valve stem seals (91-449-6A).

What owners add. Threads about 1991s keep naming a rear intake manifold gasket leaking at the back of the engine, a heater core that soaks the passenger carpet, Bose amplifiers, leaking rack boots and burnt automatic fluid. Everything a 1991 shares with every C4, from headlight motor bushings to weatherstrips and cold steering, is in Known C4 problems.

The VIN. Corvette Action Center’s 1991 identification page (opens in new tab) gives the ranges, and GM’s production total checks them: 18,595 L98 cars plus 2,044 ZR-1s make 20,639.

Engine. L98 suffix codes are ZTA (automatic), ZTB (manual, oil cooler) and ZTC (automatic, oil cooler); the LT5’s is ZTK. The L98 block is cast 14093638 and its heads 10088113. A Callaway engine is recoded with Callaway’s own sequence.

The option label. GM’s Service Parts Identification label, inside the lid between the seats, lists every RPO code on the car. It is the proof for Z07, FX3, J55, G92, MN6 and ZR1, and for the paint code.

1990, 1991 or 1992? A 1990 has the 1984–1990 nose and the round taillamps (only its ZR-1 has the convex tail), and a 1990 coupe’s stop lamp sits at the top of the rear glass. A 1992 has the 1991’s body but two rectangular exhaust tips in place of four round ones, all-black dash buttons and an ASR switch for its traction control. Turquoise Metallic with the 1991 body points to a 1991, and the straight strakes behind the front wheels fit 1991–1994, as the 1994 guide notes. The tenth VIN character settles any doubt.

What gets faked. A Z07 badge (GM never made one), a ZR-1 look on an L98 coupe, and a Callaway without paper. Badges and rear fascias bolt on; the VIN, the label and the engine stamp don’t.

1. Both front belts. Pull each all the way out and let it retract; look for the 91C25 and 91C26 stickers.
2. Key on. INFL REST should flash seven to nine times and go out. Lit and staying lit is a current fault.
3. ABS. The lamp should go out after start; a pump running on its own minutes into a drive is the 91-491A-5 condition.
4. Climate control, full hot to full cold and back. Code 01 or 02 points to the programmer.
5. Starting. On an automatic, start it several times in park and neutral; a click on a car before N5107500 suggests the purple wire.
6. The nose. Before serial 103213, check the fascia paint, and ask whether it was replaced.
7. Leaks. The back of the intake manifold, the passenger footwell, the rack boots, and the harness at the oil pressure sensor clamp.
8. Stereo and dash. Every Bose speaker, the CD player and its security code, and every LCD segment, day and night.
9. The gearbox. Unburnt automatic fluid, or clean six-speed shifts.
10. FX3, if fitted. Every setting, with no SERVICE RIDE CONTROL lamp.
11. The label against the ad, for every claimed code and the paint.
12. An inspection by a shop that knows C4s, with a compression test.

How much is a 1991 Corvette worth? For an L98 car, about $11,500 at auction in 2026. From January 1 to October 22, Bring a Trailer (opens in new tab) sold eight 1991 L98 cars for $5,200 to $22,000, a median $11,502 for L98 cars (8 sales), by this site’s count of sold prices without the buyer’s fee. One six-speed convertible sold twice ($9,900, then $9,700); counted once, seven cars brought a median of $11,755.

Seven of the eight were convertibles, at a median of $11,250, from a white automatic at $5,200 to a 26,000-mile Bright Red automatic at $22,000. The one coupe, a 3,100-mile Dark Red Metallic automatic, brought $16,000. In 2025, seven L98 cars sold at a median of $11,500. Samples this small are market color, not a valuation.

ZR-1s. Eight 1991 ZR-1s sold in 2026 for $14,250 to $36,500, a median of $32,500, and five more were bid to between $26,002 and $35,750 without selling. In 2025, eight sold at a median of $33,750, among them a 643-mile yellow car at $46,500 that its seller called Competition Yellow; GM’s 1991 yellow is code 35, so that name is the seller’s.

Hagerty’s #3 (good) values, in an archived copy of its C4 page (opens in new tab) from February 8, 2026: $10,600 coupe, $13,000 convertible, $21,800 for a ZR-1, and $29,400 and $34,300 for Callaway coupes and convertibles. Neighbors on the same table: 1990 at $11,100 and $13,500, 1992 at $8,800 and $11,500. classic.com’s 1991 page wasn’t readable for this guide. That’s what values did, not a forecast, and the best Corvette years guide puts a 1990 or 1991 L98 on its C4 budget path.

Buy a 1991 coupe with the six-speed: 250 hp, the 3.45 axle, the 1990’s cabin and the body that looked like the ZR-1’s for half a ZR-1’s price new. A G92 automatic coupe is the other 250 hp coupe, and GM’s order rules mean it came with FX3 or Z07 and the oil cooler too. Let the label prove MN6 or G92, and add Z07 if your roads are smooth and there’s an autocross in your future: 733 were built, and it’s a stiff starting point for the upgrades you’ll want anyway.

The convertible is the open-air budget path at around $11,000, and for 1991 a six-speed convertible makes 250 hp too. Whichever body, insist on belts that retract and an INFL REST lamp that flashes and goes out.

The ZR-1 is a different purchase at three times the money; buy it by the ZR-1 guide’s rules. A Callaway needs its paper. Compare before deciding: the C4 guide’s pick for most buyers is a 1995 or 1996, and a 1990 costs about the same with the old body and the one-year airbag fault. Of the two L98 years with the newer cabin, the 1991 wears the better body, and it’s a lot of America’s sports car for about $11,500. One that sits wants a battery maintainer and a cover.