The third generation Corvette lasted for 14 years and became an American icon. Glassfibre means no body rust either.
Although the C3 Corvette was born in the 1960s and passed away in the 1980s, these cars just seem to encapsulate 1970s American automobile extremes. They were loud, brash, huge and aggressively styled but also suffered from the same safety and emissions emasculations that bedeviled all US cars of the era, with V8 power peaking at (a reported) 560bhp in 1969 but dropping as low as 165bhp during the mid-1970s.
The design dated back to 1965 and the Mako Shark II concept car. However, thanks to the continuation of glassfibre for the main body – which had been in use since the first Corvette of 1953 – much of the chassis, running gear and engines could be carried over from the previous Corvette generation. As before, convertibles and coupes were available, but the ‘plastictops’ had removeable roof panels and rear window. That sports car essential, pop-up headlamps, were also fitted.
The C3 gradually moved away from pure sports car towards being a GT – chrome bumpers disappeared for 1974 and convertibles vanished the following year. Production ended in 1982.
TORQUE 285lb ft@4000rpm
MAXIMUM SPEED 124mph
Fuel consumption 13-19mpg
TRANSMISSION RWD, 4-spd manual or 3-spd auto
WHAT TO LOOK FOR
On the glassfibre shells, you should look for stress cracks and starring developing around door, bonnet (sorry, hood) and boot (we mean, of course trunk) apertures, plus the windscreen and wheelarches. Problems are more likely on convertibles, but also look for issues with the latches and weatherstrips on T-top coupes – they can leak. Uneven or differing paint or rough GRP patches points to repair, possibly after an accident. Wide or uneven gaps in the panels also point to previous crash damage. It’s important to get underneath and check the steel frame for rust, especially the rear suspension trailing arm mountings and the bottom of the windscreen pillars. The ‘rubber’ bumpers tend to disintegrate and are difficult to refit.
The V8 engines are rugged and unstressed in the Corvette. Obviously, keeping cool can be an issue, so keep an eye on the temperature and look for ‘mayonnaise’ under the oil filler cap and mixing of oil and water, denoting head gasket issues or even a warped cylinder head. Check the coolant isn’t rust-coloured and there’s no excessive exhaust smoke under acceleration. Oil drips are quite common but shouldn’t be big leaks, especially not from the bellhousing which suggests a rear engine seal past its best. Oil around the bottom radiator hose points to the front seal being worn.
Both manual and automatic gearboxes are usually quite trouble-free, but age will bring synchromesh issues on manuals as well as noise and difficult selection. Autos should change up and down smoothly.
What lies beneath?
The C3 continued with the independent rear suspension of the C2 and it’s quite complex, requiring somebody with knowledge to set it up properly. Clunks from underneath point to the rear trailing arm front bushes having failed, while squeaky clatters suggest a driveshaft universal joint is protesting. All C3s have four-wheel disc brakes, which are prone to rust in the lines and calipers. Conscientious owners often fit stainless steel replacements.
The inside story
Check for damp carpets as soft-top/roof panel leaks are common. Upholstery is leather or vinyl – the former lasts longer but is costlier to repair, while the latter splits around seams. Try out all the electrics, as dodgy/corroded connections and bad earths (due to the high GRP content) can cause things to stop functioning. Don’t forget the vacuum operated pop-up headlights (and, on earlier cars the windscreen wiper covers) as the system – a complicated maze of hoses, valves and actuators – is prone to leaks.
Corvettes come closer than other classic US machines to what we over on this side of the Big Pond regard as a proper sports car drive. They’ve actually got half-decent handling, thanks to that enormously robust chassis and lighter weight plastic body – they certainly behave better than a Mustang. Even at their most strangulated, there’s still enough muscle for entertaining performance and those that do have the power the V8 Gods intended are just blistering.
But, essentially, it’s the looks and status that most recommend the C3. They’re such a famous and distinctive shape, yet they’re not seen that often over here. So, you’ll never be short of attention. And, who knows, maybe some of the adoring public will have a whip-round to help finance the fuel bills.