Because of this, it was decided by Chevrolet management that they should treat the 1971 model year as an extension of the 1970 line, which meant that the Corvette – for better or worse – would remain essentially unaltered between the two model years.
The 1971 Corvette was virtually unchanged from 1970. (Image courtesy of GM Media.)Because the production of the cars would remain virtually unchanged from 1970 to 1971, production lines in the St. Louis Corvette plant were able to work in earnest to produce – to create – a more trouble-free car. In fact, the (more than) 500 men and women that worked each shift at the Corvette plant were highly motivated to build a better machine, knowing that they were fortunate not to be part of the many facilities across the country that mass-produced “faceless utility cars”, but rather a well-respected, much sought after sports car. Vince Shanks, the plant manager of the St. Louis Corvette Manufacturing Plant, was quoted as saying “When you ask a guy where he works in St. Louis, he’ll tell you ‘Corvette’ rather than ‘Chevrolet.’ Every Corvette he sees on the road is one he’s worked on. That’s quite an incentive.”
Because the production of the cars would remain virtually unchanged from 1970 to 1971, production lines in the St. Louis Corvette plant were able to work in earnest to produce – to create – a more trouble-free car. In fact, the (more than) 500 men and women that worked each shift at the Corvette plant were highly motivated to build a better machine, knowing that they were fortunate not to be part of the many facilities across the country that mass-produced “faceless utility cars”, but rather a well-respected, much sought after sports car. Vince Shanks, the plant manager of the St. Louis Corvette Manufacturing Plant, was quoted as saying “When you ask a guy where he works in St. Louis, he’ll tell you ‘Corvette’ rather than ‘Chevrolet.’ Every Corvette he sees on the road is one he’s worked on. That’s quite an incentive.”
The 1971 Corvette’s arrival also came in conjunction with a flurry of new federal regulations that forced manufacturers to reassess the types of cars they were producing.
In addition to the Federally sanctioned mandates on reducing exhaust emission outputs, Edward Cole (who was now president of General Motors) had decreed that all 1971 GM cars would be capable of running on fuel with a Research Octane Number (RON) no higher than 91 Octane.
According to Cole’s calculations, this octane rating was low enough for the fuel companies to begin marketing the lead-free regular gasoline needed to avoid fouling catalytic “reactors” (known as converters today) that were going to be required automobile engines. This reduction in fuel octane rating would translate into a reduction in engine compression (now just 8.5:1) and horsepower (a mere 270 bhp in the stock 350 engine.)
Somewhat surprisingly, these sanctioned emissions and fuel requirement changes didn’t only impact Corvette’s base engine. To the contrary, a notable reduction in compression – and power – was seen on almost all of the engines offered in the 1971 Corvette. The solid lifter, small block LT1 engine, which had boasted 370 horsepower in 1969, was now rated at a more modest 330 horsepower with a 9.0:1 compression ratio. The big-block engines also received the same treatment. The LS5 454 cubic inch big-block came equipped with 365 horsepower at 4800 rpm, and a new aluminum-head big-block engine identified as the LS6 was rated at 425 horsepower at 5600 rpm. Given the output numbers of these engines, there were few who would argue that the 1971 Corvette was weak, although most would agree that it was a far cry from the Corvettes that emerged in the unregulated era of muscle car performance.
Interestingly, the 1971 454 LS6 engine was actually a detuned version of 1970’s planned but cancelled 460 horsepower LS7. While the engines were fundamentally the same, the LS6 was developed to operate on low-lead, lower-octane fuel, giving it the clear marketing advantage over its never-to-be LS7 predecessor, despite its lower horsepower rating.
The LS6 engine featured aluminum heads, and its pistons were modestly domed, which helped it achieved the slightly higher 9.0:1 ratio. One unique feature for this high-performance big-block engine was that it could be ordered with an automatic transmission, although not when it was combined with the ZR2 package. Still, such an $1,220.70, and as such, only 188 were ever sold. Even Duntov, who had pushed for the development of the LS6, had later been quoted in Car & Driver as saying, “Maybe I make mistake. Aluminum heads are expensive and that weight (reduction) doesn’t matter on the street.”
Still, it was the right kind of engine to lead the Corvette lineup, and that was where it’s real marketing value mattered most.
Because of Cole’s far reaching directive, Chevrolet engineers had only a matter of weeks rather than months to adjust all of their engines – and not just those for the Corvette. Because of this, very few changes were made to the 1971 Corvette – other than those made to the engines.
DID YOU KNOW: The 1971 Corvette production specs called for the use of amber parking light lenses. However, most 1971 Corvettes came equipped with clear lenses and amber bulbs, which was a carry-over from the 1970 model year. Additionally, the 1971 Corvette included an optional custom interior trim package which included leather seat trim, wood-grain accents, and lower carpet trim on interior door panels, wood grain accents on the console and special cut-pile carpeting.
There were minor advances made, such as an easier-to-open fuel filler door, and an automatic transmission selector quadrant that illuminated during night time operation, but nothing that really separated the 1971 model from earlier years. However, the 1971 Corvette would be the last Corvette model to feature the fiber-optics light monitoring system, and it is believed that many late model 1971 Corvettes were actually manufactured without the fiber optics. (While not a notable change to the 1971 Corvette, the removal of the fiber-optic system allowed Chevrolet to make the optional anti-theft alarm system (RPO UA6) standard equipment for the 1972 model.)
For 1971, Chevrolet offered consumers not one, but two special purpose (racing) packages. The first of these was the RPO ZR1 package which utilized the aforementioned LT1 engine, and also included a heavy-duty, four-speed, close ratio transmission (RPO M22), heavy-duty power brakes, a special aluminum radiator, a metal fan shroud, a transistor ignition, and a revised suspension with special springs, shocks, spindle-strut shafts, and front and rear stabilizer bars (though it has since been determined that the 1971 ZR1 has appeared with and without rear stabilizers.) When equipped with the ZR1 package, consumers were unable to include many of the more “luxurious” amenities available power windows, a rear window defroster, air conditioning, power steering, deluxe wheel covers, an alarm system, and any type of AM/FM radio.
The second special purpose package that Chevrolet offered was RPO ZR2. This second special purpose package was identical to the ZR1, except that instead of a small block LT1 engine, the ZR2 came equipped with the aforementioned 454 cubic inch LS6 engine.
Like the ZR1, the ZR2 package also included the same ordering restrictions – namely none of the “creature comfort” amenities that were appealing to many consumers.
It may be for that very reason – or perhaps that combined with the substantial cost increase that each option carried with it – that so few of either performance packages was ordered during that model year. In total, only eight Corvettes were ordered with the ZR1 option, and only twelve were ordered with the ZR2.
Beyond these items, the 1971 Corvette carried on much as its 1970 predecessor had. Pricing for the 1971 Corvette increased, though only modestly, to $5,259 for a convertible, and $5,496 for the coupe.
With production now recovered from the UAW strike, sales of the 1971 Corvette improved, resulting in a total of 21,801 Corvettes sold for that model year, with the coupe taking a 2 to 1 sales lead over the convertible – a result which many believed was the result of the C3’s introduction of T-tops in 1969. Prior to that point, Corvette convertibles had actually dominated sales, but starting in 1969, more coupes than convertibles were sold with each model year that passed.
In 1971, the result was total coupes to just 7,121 convertibles – a fact that GM would take under serious consideration in the years to come, and also a fact that would lead to a shocking, and some consider controversial, decision for the 1976 model year.
Two-door convertible/coupe, front engine, rear wheel drive
St. Louis, Missouri
Uniconstruction: fiberglass reinforced plastic (FRP or “fiberglass”) body, backboned by a steel cage outlining the passenger compartment. Principal members – underbody, front and rear end assemblies, dash panel and hinge pillars are bonded, riveted, or bolted together and to each other. Hood is plastic with bonded plastic reinforcement. Coupe: two removable roof panels and removable rear window. Frame: all welded, full length, ladder construction with 5 crossmembers. Side Rails and intermediate crossmembers box section; front crossmember box girder section. Eight body-mounting points.
Type and Description: Independent, SLA type, coil springs with center mounted shock absorbers, spherical joint steering knuckle pivots.
Front Coil Springs
Make & Type
Right-hand Helix Variable rate
Spring Rate (lb. per in.)
Rate at Wheel (lb. per in.)
Design Load at Spring
9.99 in. @ 1395 lbs. (9.99 in. @ 1540 lbs.
Front Stabilizer Bar
Hot rolled steel
.750 with 350ci engine, .9375 with 454ci engine
Suspension – Back
Type and Description: Full Independent rear suspension with frame-anchored differential unit. Position of each wheel established by three links: tubular axle drive shafts, transverse strut rods, torque control arms. Vertical suspension loads taken by transverse leaf springs. Built-in camber adjustment at strut rod inner ends.
Rear Leaf Springs
Number of Leaves
Chrome carbon steel
Length, width, height
46.36 x 2.25 x 2.121
Rear Shock Absorbers:
Direct, double-acting, hydraulic
Caliper Disk – 4 Wheel Hydraulic
Delco-Moraine Vacuum Assisted Powered Brakes
Drum diameter, front (in.):
11.75 x 1.25
Drum diameter, rear (in.):
11.75 x 1.25
Swept Drum Area Effective area:
Wheels & Tires
Wheels & Tires Specs
Short spoke spider, welded steel
15″ x 8.00
F70 x 15 — 4 PR. 2-Ply Tubeless Nylon
F70 x 15 — 4 PR, 2-Ply Red Stripe Nylon
F70 x 15 — 4 PR, 2-Ply White Stripe Nylon
Steering Specs – Manual Steering
Semi-reversible gear with ball-nut driven by recirculating anti-friction bearings, energy-absorbing steering column, steering damper attached to relay rod; two position steering knuckle arm attachment for street and fast ratio steering. Adjustable steering column available optionally.
Wheel Diameter (in.)
Turns, Stop to Stop
37 ft. (outside front), 39 ft. (outside front)
Steering Specs – Power Steering RPO N40
(Specifications are the same as Manual Steering except the following):
Hydraulic; pump powered cylinder assisted linkage
Wheel Turns (Lock to Lock)
1971 Corvette Exterior Dimensions
Hard Top Dimensions
Exterior Dimensions (Hardtop)
Interior Dimensions (Hardtop)
Total Body Width:
Front Track Width:
Rear Track Width:
Min. Ground Clearance
Soft Top Dimensions
Exterior Dimensions (Soft Top)
Interior Dimensions (Soft Top)
Total Body Width:
Front Track Width:
Rear Track Width:
Min. Ground Clearance
Exterior Dimensions (Coupe)
Interior Dimensions (Coupe)
Total Body Width:
Front Track Width:
Rear Track Width:
Min. Ground Clearance
2 – Driver & Passenger
Curb Weight (lbs)
– Convertible with soft top
– Convertible; C07 with folding top
– Convertible; C07 less folding top
Interior Passenger Volume (cu. ft)
Interior Trunk Volume (cu. ft)
Fuel Capacity (gallons):
4.0 for 350ci. engines (capacity of crankcase less filter – refill)
5.0 for 454ci engines (capacity of crankcase less filter – refill)
Coolant capacity without heater (qts.)
18 for RPO LT1 engine
22 for LS5 engine
12 Volt, 62AH for 350ci. engines
12 Volt, 80AH for 454ci. engines
1971 Corvette Transmission Identification & Transmission Number
3 & 4-Speed Manual (Saginaw) – Stamped on right-hand side of case in the upper forward corner.
4-Speed (Muncie) – Stamped on the top right-hand side of the case.
Turbo Hydra-Matic Automatic – Name plate tag on right-hand side of case.
Transmission Identification Example:
P – Type Designation
P – Muncie
1 – Year. 1 – 1971
E13A – Production Month and Date.
E – Designates Month (See Chart Below.)
A – Jan.B – Feb.C – Mar.D – Apr.E – MayF – JuneG – July
13 – Designates Day of the month.
A – M20, or B – M21
Transmission Number Example:
7 – Model. 7 – Corvette
1 – Model year. 1 – 1971
S – Assembly Plant Designation. S – St. Louis
100001 – VIN Sequential Serial Number
1971 Corvette Factory Options
Base Corvette Sport Coupe
Base Corvette Convertible
Custom Interior Trim
Custom Shoulder Belts (std with coupe)
Auxiliary Hardtop (for convertible)
Vinyl Covering (for auxiliary hardtop)
Rear Window Defroster
Optional Rear Axle Ratio
454ci, 390hp Engine
454ci, 425hp Engine
350ci, 330hp Engine
4-Speed Manual Transmission, close-ratio
4-Speed Manual Transmission, close ratio heavy duty
Turbo-Hydro-matic Automatic Transmission
Tilt-Telescopic Steering Column
Deluxe Wheel Cover
White Stripe Tires, F70x15 nylon
White Letter Tires, F70x15 nylon
Heavy Duty Battery (std with LS5)
AM-FM Radio, stereo
Special Purpose LT1 Engine Package
Special Purpose LS6 Engine Package
Base Corvette Sport Coupe (19437)
The base price of the 1971 Chevrolet Corvette Coupe without any optional equipment.
A 350 cubic inch, 270 horsepower engine, 4-speed wide ratio manual transmission, vinyl interior trim, and T-tops were included in the base price.
Base Corvette Convertible (19467)
The base price of the 1971 Corvette Convertible without any optional equipment.
A 350 cubic inch, 270 horsepower engine, 4-speed wide ratio manual transmission, vinyl interior trim, and a convertible top were included in the base price.
Custom Interior ( — )
Optional interior trim upgrade that included a number of custom modifications to the base interior.
The custom interior trim includes leather seat trim, wood-grain accents and carpet trim on door panels, wood-grain accents on the console, and cut-pile carpeting.
Power Windows (A31)
Factory installed power driver and passenger windows.
Custom Shoulder Belts (A85)
An addition to the standard lap safety belt that crosses over the shoulder for added safety.
The shoulder belts option were included with all Corvette coupes at no additional charge. The option was also available on the Corvette convertible, but at an additional cost.
Auxiliary Hardtop (for convertibles) (C07)
An optional hard-top that could be installed in lieu of the convertible top.
Vinyl Covering (for Auxiliary Hardtop) (C08)
This option provided an external vinyl liner application to the auxiliary hardtop
The vinyl covering provided a faux convertible top appearance even when the hardtop was mounted on the car.
Rear Window Defroster (C50)
An optional rear window forced air defroster.
This option was not available to consumers when RPO ZR1 or ZR2 was ordered.
Air Conditioning (C60)
Factory installed air-conditioning.
Heater integrated, manually controlled by knobs on instrument control panel that operate bowden cables to activate various doors/ducts and switches to operate system.
System includes evaporator, blower, condenser, receiver-dehydrator, refrigerant (freon) tank, air intake assembly and duct assembly for both systems.
Optional Rear Axle Ratio (ZQ1) – Rear axle ratio selection.
Power Brakes (J50)
Vacuum power assisted brakes; includes dual circuit master cylinder.
454ci, 365hp Engine (LS5)
Optional high-output, big-block V-8 engine.
454ci, 425hp Engine (LS6)
Optional high-output, big-block V-8 engine.
The 454 cubic inch LS6 engine with 425 horsepower with a detuned version of 1970’s planned but canceled 460 horsepower LS7 engine.
The LS6 engine was designed to run on low-lead fuel.
The LS6 featured aluminum heads and could be ordered with an automatic transmission, although not when combined with the ZR2 package.
350ci, 330hp Engine (LT1)
Optional higher-output, small block V-8 engine.
4-Speed Manual Transmission, Close Ratio (M21)
A close ratio version of the M20 Muncie 4-speed manual transmission.
The gear ratios for the RPO M21 Close Ratio 4-Speed Manual Transmission are: 1st Gear – 2.20:1, 2nd Gear – 1.64:1, 3rd Gear – 1.28:1, 4th Gear – 1.0:1 (Direct).
4-Speed Manual Trans, Close Ratio, Heavy Duty (M22)
A heavy-duty version of the Close Ratio Manual Transmission.
This heavy duty transmission came equipped with a fine spline input shaft, a larger diameter output shaft and gear teeth that utilized reduced helix angles. It was equipped with the following gear ratios: 1st Gear – 2.20:1, 2nd Gear – 1.64:1, 3rd Gear – 1.27:1, and 4th Gear – 1.00:1.
Turbo Hydra-Matic Automatic Transmission (M40)
An optional, three-speed automatic transmission.
The Turbo Hydra-Matic Automatic Transmission consisted of a 3-element hydraulic torque converter and compound planetary gear set. It was equipped with the following gear ratios: 1st Gear – 2.48:1, 2nd Gear – 1.48:1, and 3rd Gear – 1.00:1.
The M40 Turbo Hydra-Matic transmission was a no-cost option with the base 350 cubic inch, 270 horsepower engine, but cost $100.35 when ordered with the LS5 or LS6 engine option.
It was not available with the LT1, ZR1 or ZR2 options.
Tilt Telescopic Steering Column (N37)
An optional, adjustable steering column and tilt-angle adjustable steering wheel.
The Telescopic Steering Column changes the drivers distance from the steering wheel by literally telescoping the steering wheel closer to or further away from the vehicle operator.
Power Steering (N40)
Hydraulically assisted power steering.
This option was not available to consumers when the RPO ZR1 was ordered.
Deluxe Wheel Covers (P02)
Optional deluxe wheel covers.
This option was not available to consumers when the RPO ZR1 was ordered.
White Stripe Tires, F70 x 15, nylon (PT7) – Standard size tires with a special 3/8″ wide white sidewall stripes.
White Letter Tires, F70x 15, nylon (PU9)
Standard size tires with a special 3/8″ wide white sidewall letters.
Heavy Duty Battery (T60)
An optional, heavy-duty battery which provided additional cranking amps.
While available as an option on any 1971 Corvette, the Heavy Duty Battery came standard with the LS5 and LS6 equipped Corvettes.
Alarm System (UA6)
A factory installed alarm system.
When activated, the alarm system would trigger the horn to sound in a repetitive pattern of short bursts.
AM-FM Radio (U69)
A standard/stock dealer installed Corvette radio for model years 1968-1971.
The radio broadcast only a mono signal.
AM-FM Radio, Stereo (U79)
An optional dealer installed Corvette radio for model years 1968-1971.
This radio option provided a true stereo signal.
This radio featured green lettering.
This option was not available to consumers when the RPO ZR1 was ordered.
Special Purpose Engine Package (ZR1)
Optional performance and handling upgrade.
RPO ZR1 included the 350 cubic inch, 330 horsepower LT1 engine, a 4-Speed, Close Ratio, Heavy Duty Manual Transmission (M22), heavy-duty power brakes, transistor ignition, special aluminum radiator, and special springs, shocks, and front & rear stabilizer bars.
When the ZR1 option was ordered, the following options were not available on the 1971 Corvette: Power
Windows (A31), Rear Window Defroster (C50), Air Conditioning (C60), Power Steering (N40), Deluxe Wheel Covers (P02), Alarm System (UA6), AM-FM Radio (U69), AM-FM Radio, stereo (U79).
ZR1’s came equipped with metal fan shrouds.
Special Purpose Engine Package (ZR2)
Optional performance and handling upgrade.
RPO ZR2 included the 454 cubic inch, 425 horsepower LS6 engine, a 4-Speed, Close Ratio, Heavy Duty Manual Transmission (M22), heavy-duty power brakes, transistor ignition, special aluminum radiator, and special springs, shocks, and front & rear stabilizer bars.
When the ZR2 option was ordered, the following options were not available on the 1971 Corvette: Power Windows (A31), Rear Window Defroster (C50), Air Conditioning (C60), Power Steering (N40), Deluxe Wheel Covers (P02), Alarm System (UA6), AM-FM Radio (U69), AM-FM Radio, stereo (U79).
The 1971 Corvette was one of the least changed in appearance from a previous model year. A labor dispute in 1969 caused production of the 1969 Corvette to run long, shortening normal 1970 production by over four months. As a result, Chevrolet treated the 1971 production year as an extension of the shortened 1970 production run.
Another reason that the 1971 Corvette was virtually unchanged in appearance was because of an edict by General Motors to reduce octane requirements for 1971 engines. Because of this directive, Chevrolet engineers focused their efforts on redesigning engines instead of modifying the current Corvette design.
1971 engines were actually de-tuned variants of their 1970 counterparts. The intent behind General Motors’ engine octane reduction initiative to 91 octane (research) was to give oil companies phase-in time for the unleaded fuels that were required on vehicles equipped with catalytic converters (including the Corvette.)
Production specifications called for amber parking light lenses, but most 1971 Corvettes had clear lenses with amber bulbs as they did in 1970.
The fuel filler door hardware was redesigned in 1971 for easier access.
Seating pleats ran fore and aft for vinyl seats and for most leather seats, although later production 1971 leather seats had pleats running side to side.
The 1971 Corvette was the last model year to feature the fiber-optic light monitoring system, although some of the late model 1971’s were actually missing the fiber optics. The elimination of this feature allowed for the inclusion of the anti-theft system as standard equipment in the 1972 Corvette the following year.
1971 Corvette Recalls
Make: Chevrolet Model: Corvette Model Year: 1971 Manufacturer: Cardone Industries, Inc. Mfr’s Report Date: May 07, 2003 Nhtsa Campaign Id Number: 03e032000 Nhtsa Action Number: N/a Component: Service Brakes, Air:disc:caliper Potential Number Of Units Affected: 15,899 Summary: Remanufactured Rear Brake Calipers, Part Nos. 18-7019, 18-7020, 16-7019, And 16-7020, Manufactured From February 1, 2002, To April, 25, 2003., And For Use On 1965 Thru 1982 Chevrolet Corvettes. The Subject Brake Calipers Were Manufactured Using Improperly Manufactured Piston Seals. These Seals Are Intended To Prevent Fluid Leakage Between The Caliper Housing And The Pistons. These Brake Calipers Are For Use Only On 1965 Thru 1982 Chevrolet Corvette Vehicles. This Recall Does Not Involve General Motors Corporation Or Any Of Its Products. Consequence: Under These Conditions, The Vehicle Operator May Not Be Able To Stop The Car, Possibly Resulting In A Vehicle Crash. Remedy: Cardone Will Notify Its Customers And All Unsold Inventory Will Be Repurchased And Will Provide A Full Refund To Customers. Owner Notification Is Expected To Begin During May 2003. Owners Who Take Their Vehicles To An Authorized Dealer On An Agreed Upon Service Date And Do Not Receive The Free Remedy Within A Reasonable Time Should Contact Cardone At 215-912-3000. Notes: Also, Customers Can Contact The National Highway Traffic Safety Administration’s Auto Safety Hotline At 1-888-dash-2-dot (1-888-327-4236).
1971 Corvette Service Bulletins
There are no known service bulletins listed for the 1971 Chevrolet Corvette.
1971 Corvette Common Issues
The following list of common issues is intended for individual reference only, and may not reflect the specific issues of every 1971 Corvette. This information comes from a variety of sources including the NHTSA Defects Reports pages. While the intent of this page is to identify the common issues pertaining to the 1971 Corvette, it is not an all-inclusive list and should be used for reference only.
1971 C3 Corvette Mechanical Issues
PARKING BRAKE ASSEMBLY
The parking brake assembly on C3 Corvettes are known to have a number of issues including: stretching of the parking brake cable and seizure of the parking brake shoes and levers due to excessive rust. Fortunately, a number of replacement parking brake assemblies are available from aftermarket retailers. When rebuilding the parking brake assembly it is highly recommended that the entire assembly be replaced. A complete rebuild will include the replacement of the parking brake cable, shoes, levers and pulleys. A complete rebuild should take approximately 3-5 hours.
1971 C3 Corvette External Issues
HEADLAMP ACTUATOR VACUUM LEAKS
All Corvettes from 1968-1981 can have a large vacuum leak from the headlight actuator vacuum system that will affect the engine idle. When experiencing rough idle, remove the vacuum hose and plug the fitting temporarily, then check engine performance. See Transmission Modulator Vacuum Leaks above for additional information.
The rubber hoses and other components of the headlight vacuum system are known to wear out. In many instances, only one of the headlight assemblies will operate. Always check all rubber vacuum lines when even a single headlight assembly is not operating properly as many times, it the result of a failed or collapsed line.
Over time, the door hinges on all C3 Corvettes fatigue and begin to fail, causing the doors to sag and other alignment issues including broken door seals, water leaks, and road noise. To prolong the hinge life, lubricate the hinges regularly. In the event that the hinges do sag, replacing the hinge bushings and pin is also an option, although replacing the upper hinge pin will require the removal of the dashboard speedometer cluster.
1971 C3 Corvette Interior Issues
The shifter console is the focal point of any Corvette interior. Due to natural wear, the console becomes worn and can become an eyesore. Fortunately, restoring the shifter console is a fairly straight forward task. The entire shifter console plate can be removed as a single unit and does not require the use of any tools. Replacement components are available from aftermarket distributors.
1971 Corvette Maintenance Schedule
The time or mileage intervals indicated on this website are intended as a guide for establishing regular maintenance and lubrication periods. Sustained heavy duty or high speed driving, or driving under adverse conditions may require more frequent servicing.
Additional Maintenance & Lubrication
In addition to the items listed above, it is also recommended that the following items are inspected every 300 miles or 2 weeks, whichever comes first:
Check Tire Pressure
Check Battery Water Level
Check Oil Level In Engine
Remove air cleaner and block throttle and choke in wide open position. Hook up starter remote control cable and insert compression gauge firmly in spark plug port. Whenever the engine is cranked remotely at the starter, with a jumper cable or other means, the distributor primary lead must be disconnected from the negative post on the coil and the ignition switch must be in the “ON” position. Failure to do this will result in a damaged grounding circuit in the ignition switch.
Crank engine through at least four compression strokes to obtain highest possible reading. Check and record compression of each cylinder. If one or more cylinders reads low or uneven, inject about a tablespoon of engine oil on top of pistons in low reading cylinders (through spark plug port.) Crank engine several times and recheck compression. If compression comes up but does not necessarily reach normal, rings are worn. If compression does not improve, valves are burnt, sticking or not sealing properly. If two adjacent cylinders indicate low compression, the cause may be a head gasket leak between the cylinders. Engine coolant and/or oil in cylinders could result from this defect.
The adjustments described apply to all carburetors used, except as noted. All adjustments are made with the engine at normal operating temperature.
Idle Speed (1971)
The 1971 models use a Combined Emission Control Valve (C.E.C.) to adjust idle speed and adjust ignition according to demand.
Disconnect the vacuum hose at the distributor and plug, remove gas tank cap, and be sure A/C is off. Manually extend C.E.C. valve plunger to contact the throttle level at the limit of its travel. Adjust plunger length to obtain specified rpm. Adjust idle mixture screw as previously described, if necessary.
Idle Speed and Mixture – Holley 2300
All adjustments are same as previously described except as follows: On models equipped with idle stop solenoid, adjust idle stop solenoid screw to give 1000 rpm, then adjust idle mixture adjusting screw to specified rpm. Turn idle mixture screw in (leaner mixture) until engine speed drops 20 rpm, then turn out 1/4 turn. Disconnect lead at idle stop solenoid (throttle level will rest against regular stopscrew.) Adjust this stopscrew for idle speed of 500 rpm. Do not change setting of idle stop solenoid stopscrew or idle mixture screw.
Fast Idle (1966-1976)
With the transmission in neutral, position the cam follower on the high step (2nd step, 1971-1972) of the fast idle cam. Adjust fast idle screw of Rochester carburetors to obtain recommended fast idle speed. Bend fast idle lever on Holleys. On 1970-72 models, disconnect transmission controlled spark solenoid.
With slow idle speed correctly adjusted, fully open choke and make sure fast idle cam follower is off steps of cam. With dashpot fully compressed, adjust for 1/16″ clearance between dashpot plunger and throttle lever.
Remove the air cleaner and check to see that choke valve and rod more freely. Disconnect choke rod at choke lever. Check choke adjustment by holding choke valve closed and position rod so that it contacts stop. If necessary, adjust rod length by bending rod at offset. Bend must be such that rod enters choke lever hole freely and squarely. Connect rod at choke lever and install air cleaner.
Air Injection Reactor (A.I.R.)
Description and Operation
The A.I.R. system is used to burn the unburned portion of the exhaust gases to reduce its hydrocarbon and carbon monoxide content. The system forces compressed air into the exhaust manifold where it mixes with the hot exhaust gases. The hot exhaust gases contain unburned particles that complete their combustion when the addition air is supplied.
The system consists of: An air pump, diverter valve, check valve(s), AIR pipe assemblies and connecting hoses and fittings. Carburetors and distributors for AIR engines are made to be used with the system and should not be replaced with components intended for use with engines that do not have the system.
The air pump is a two-vane pump which compresses fresh filtered air and injects it into the exhaust manifold. The pump consists of: a housing, centrifugal filter, set of vanes that rotate about the centerline of pump housing bore, the rotor, and the seals for the vanes. The centrifugal filter is replaced by first removing the drive belt and pump pulley; then pulling filter off with pliers. Care should be taken to prevent fragments from entering the air intake hole. NOTE: A new filter may squeal when first put into operation. Additionally, GREAT CARE should be taken in working on the compressor as the aluminum used is quite soft and thin. The air pump is operating satisfactorily when the air flow from it increases as engine speed increases.
The air hoses should be replaced only with hoses which are designed for AIR system use, as no other type hoses can withstand the high temperature.
Check and Adjust Dwell
Start engine then check ignition dwell. With engine running at idle, raise the adjustment screw window and insert an Allen wrench in the socket of the adjusting screw. Turn the adjusting screw as required until a dwell reading of thirty degrees is obtained. A two degree variation is allowable for wear. Close access cover fully to prevent the entry of dirt into the distributor. If a dwell meter is not available, turn adjusting screw clockwise until engine starts to misfire, then turn screw one-half turn in the opposite direction to complete adjustment.
Slowly accelerate engine to 1500 rpm and note dwell reading. Return engine to idle and note dwell reading. If dwell variation exceeds specifications, check for worn distributor shaft, worn distributor shaft bushing or loose breaker plate.
Remove distributor cap, clean cap and inspect for cracks, carbon tracks and burned or corroded terminals. Replace cap where necessary. Clean rotor and inspect for damage or deterioration. Replace rotor where necessary. Replace brittle, oil soaked or damaged spark plug wires. Install all wires to proper spark plug. Proper positioning of spark plug wires in supports is important to prevent cross-firing. Tighten all ignition system connections. Replace or repair any wires that are frayed, loose or damaged.
Disconnect the distributor spark advance hose and plug the vacuum source opening. Start engine and run at idle speed. Aim timing light at timing tab. The markings on the tabs are in two degree increments (the greatest number of markings on the “A” side of the “Q”). The “O” marking is TDC (Top Dead Center) and the BTDC settings fall on the “A” (advance) side of the “O”. Adjust the timing by loosening the distributor clamp and rotating the distributor body as required, then tighten the clamp, and recheck timing. Stop engine and remove timing light and reconnect the spark advance hose.
Inspect each plug individually for badly worn electrodes, glazed, broken or blistered porcelains and replace plugs where necessary. Clean serviceable spark plugs thoroughly, using an abrasive-type cleaner such as sand blast. File the center electrode flat. Inspect each spark plug for make and heat range. All plugs must be of the same make and number. Adjust spark plug gaps to .035 in. using a round feeler gauge. If available, test plugs with a spark plug tester. Inspect spark plug hole threads and clean before installing plugs. Install spark plugs with new gaskets and torque to specifications. Connect spark plug wiring.
Transistorized Distributor (H.E.I. System)
There are no moving parts in the ignition pulse amplifier, and the distributor shaft and bushings have permanent type lubrication, therefore no periodic maintenance is required for the magnetic pulse ignition system.
Distributor (Breaker Point System)
Check the distributor centrifugal advance mechanisms by turning the distributor rotor in a clockwise direction as far as possible, then releasing the rotor to see if the springs return it to its retarded position. If the rotor does not return readily, the distributor must be disassembled and the cause of the trouble corrected.
Check to see that the vacuum spark control operates freely by turning the movable breaker plate counter-clockwise to see if the spring returns to its retarded position. Any stiffness in the operation of the spark control will affect the ignition timing. Correct any interference or binding condition noted.
Examine distributor points and clean or replace if necessary. Contact points with an overall gray color and only slight roughness or pitting need not be replaced. Dirty points should be cleaned with a clean point file. Use only a few strokes of a clean, fine-cut contact file. The file should not be used on other metals and should not be allowed to become greasy or dirty. Never use emery cloth or sandpaper to clean contact points since particles will embed and cause arcing and rapid burning of points. Do not attempt to remove all roughness nor dress the point surfaces down smooth. Merely remove scale or dirt. Clean cam lobe with cleaning solvent, and rotate cam lubricator wick end (or one-hundred-eighty degrees as applicable). Replace points that are burned or badly pitted.
Where prematurely burned or badly pitted points are encountered, the ignition system and engine should be checked to determine the cause of trouble so that it can be eliminated. Unless the condition causing point burning or pitting is corrected, new points will provide no better service than the old points.
Check point alignment then adjust distributor contact point gap to .019″ (new points) or .016″ (used points). Breaker arm rubbing block must be on high point of lobe during adjustment. If contact points have been in service, they should be cleaned with a point file before adjusting with a feeler gauge.
Check distributor point spring tension (contact point pressure) with a spring gauge hooked to breaker lever at the contact and pull exerted at 90 degrees to the breaker lever. The points should be closed (cam follower between lobes) and the reading taken just as the points separate. Spring tension should be 19-23 ounces. If not within limits, replace. Excessive point pressure will cause excessive wear on the points, cam and rubber block. Weak point pressure permits bouncing or chattering, resulting in arcing and burning of the points and an ignition miss at high speed.
Install rotor and distributor cap. Press all wires firmly into cap towers.
Battery and Battery Cables
The top of the battery should be clean and the battery hold-down properly tightened. Particular care should be taken to see that the top of the battery is kept clean of acid film and dirt. When cleaning batteries, wash first with a dilute ammonia based or soda solution to neutralize any acid present and then flush off with clean water. Keep vent plugs tight so that the neutralizing solution does not enter the cell. The hold-down bolts should be kept tight enough to prevent the batter from shaking around in its holder, but they should onto be tightened to the point where the battery case will be placed under a severe strain.
To ensure good contact, the battery cables should be tight on the battery posts. Oil battery terminal felt washer. If the battery posts or cable terminals are corroded, the cables should be cleaned separately with a soda solution and wire brush. After cleaning and before installing clamps, apply a thin coating of a petrolatum to the posts and cable clamps to help slow corrosion.
If the battery has remain undercharged, check for loose or defective fan belt, defective alternator, high resistance in the charging circuit, oxidized regulator contact points, or a low voltage setting. If the battery has been using too much water, the voltage output is too high.
Inspect for deteriorated or plugged hoses. Inspect all hose connections. On engines with closed element air cleaners, inspect crankcase ventilation filter and replace if necessary. On engines with open element air cleaners, remove flame arrestor and wash in solvent then dry with compressed air.
Check the brake fluid regularly, for as the brake pads wear the level will drop rapidly. It should be replenished only with the recommended fluid. Check disc brake assemblies to see if they are wet; it would indicate a leaking cylinder.
Disc brakes do not need periodic adjustments; they are self adjusting. The pads should be replaced when the friction material gets down to 1/16″. This is when the groove in the center of the pad is gone. Check by removing wheel and looking directly into caliper.
Clutch Pedal Play
Check clutch action by holding pedal 1/2″ from floor and move shift lever between first and reverse several times, with engine running. If shift is not smooth adjust clutch. Free play with pedal released is approx. 1-1/4″ to 2″ and 2″ to 2-1/2″ for heavy duty.
At clutch lever near firewall remove clutch return spring. To decrease clutch pedal free play remove clutch pedal return spring and loosen lower nut on clutch pedal rod; take up play with upper nut. Continue until proper play is obtained, then securely tighten top nut and replace spring. To increase pedal play work nuts in opposite sequence.
Disconnect control linkage at carburetor throttle lever. Hold carburetor throttle lever in wide position. Pull control linkage to wide open position. (On vehicles equipped with automatic transmission, pull through detent.) Adjust control linkage to freely enter hole in carburetor throttle lever. Connect control linkage at throttle lever.
Throttle Linkage Adjustment (Powerglide)
Remove air cleaner, disconnect accelerator linkage at carburetor. Disconnect accelerator return and trans. road return springs. Pull upper rod forward until transmission is through detent. Open carburetor wide open, at which point ball stud must contact end of slot in upper rod. Adjust swivel on end of rod if necessary.
Pull detent switch driver to rear until hole in switch body lines up with hole in driver. Insert a 3/16″ pin through hole to depth of 1/8″, and loosen mounting bolts. Open throttle fully and move switch forward until lever touches accelerator lever. Tighten mounting bolt and remove pin.
EGR Valve Check
A rough idling engine may be caused by a malfunction of the valve. Check by pinching vacuum hose to carburetor with engine idling. If idling smooths out, the valve should be removed for cleaning or replacement if something appears to be broken.
The car should be standing on level ground and the oil level checked with the dipstick. Withdraw the dipstick, wipe it with a clean rag, replace and withdraw again. The mark made by the oil on the lower end of the dipstick will indicate the oil level. If necessary, oil should be added through the filler cap. Never let the oil level fall so low that it does not show at all on the dipstick. If in doubt, it is better to have a bit too much oil than too little. Never mix oils of different brands, the additives may not be compatible.
Engine Oil Drain and Replacement
Place a pan under the oil pan drain plug and remove plug. Be sure pan is of a large enough capacity to hold the oil. Move pan under filter and remove filter by turning if counterclockwise. Clean gasket surface of cylinder block. Coat gasket of new filter with engine oil. Thread filter into adapter. Tighten securely by hand. Do not overtighten filter. Remove drop pan.
Remove drain pan. Inspect oil pan drain plug gasket and replace if broken, cracked, or distorted. Install drain plug and tighten. Fill crankcase to required level with recommended oil. Operate engine at fast idle and check for oil leakage.
When changing oil filter, add one additional quart.
Check fluid level with engine idling, transmission in neutral and engine at normal operating temperature. Add fluid as needed to bring level to mark. Do not overfill.
Every 12,000 miles or sooner, depending on service, remove fluid from sump and add new fluid. Operate transmission and check fluid level. Every 24,000 miles the transmission sump strainer of the Turbo Hydra-Matic transmission should be replaced.
Raise car on lift, clean dirt and grease from area around the filler plug. Plug is located on side of transmission case. Remove plug and place finger tip inside hole. The oil should be just about level with the bottom edge of the hole. Add oil as needed, using a plastic syringe.
Change cam lubricator end for end at 12,000 mile intervals. Replace at 24,000 mile intervals.
With the car standing level, clean dirt and grease from area around filler plug. Remove plug and place finger tip inside hole. The oil should be just about level with the bottom edge of the hole. Add oil, with a plastic syringe, as needed.
1971 Corvette Dealers Sales Brochure
Download this 1971 Corvette Dealers Sales Brochure for a quick look at the features of the car.
1.) CORVETTE: America’s Star-Spangled Sports Car, The Complete History – Copyright 1973, Automobile Quarterly 2.) The Pocket Book of the Corvette: The Definitive Guide to the All American Sports Car – Copyright 2003, Barnes & Noble 3.) CORVETTE: Sports Car Superstar – Copyright 2005, PIL – Publications International, Ltd. 4.) Corvette Black Book – Copyright 2009, Michael Bruce Associates, Inc. 5.) The Complete Book of Corvette – Every Model Since 1963 – Copyright 2006, MBI Publishing