A UAW strike forced a two-month extension of 1969 production, which gave Chevy the time it needed to make the 1970 a better-built Corvette, and was doubtless a factor in 1969's record volume. But the strike also delayed the 1970s from reaching dealer showrooms until February, which pushed Corvette sales to its lowest point since 1962 -- a mere 17,316 units.
Cosmetic changes for the abbreviated 1970 model year were
slight. The extreme bodyside tuck-under was found to be susceptible to stone
damage, so Chevy flared the aft portions of each wheel opening, which helped
somewhat. The grille went from horizontal bars to a fine eggcrate pattern. (The
real radiator air intakes, Duntov's original slots, were on the car's
underside.) The eggcrate also appeared on the front fenders in place of the
previous four "gills." Front parking lamps switched from small, round
units to rectangular fixtures with clear lenses and amber bulbs. The dual
exhaust outlets also shifted from round to rectangular.
Total sales for the 1970 Corvette were down to the lowest point since 1962,
reflecting a production start-up delayed to January 1970.
Inside the cabin, seats were reshaped for better lateral support, more headroom, and easier access to the trunk. Shoulder belts, still separate from the lap belts, got inertia storage reels, thus ending some cockpit clutter. A redoubtable custom trim package was added to the options list that offered full cut-pile carpeting and fake wood trim on the console and doors.
Engines were again the main Corvette news for 1970. The LT1
was now genuinely available, though at a hefty $447.50. Lesser 350s returned
unchanged. The mighty L88 and ZL1 weren't even theoretically offered, though
Chevy continued to sell Can-Am engines to bona fide teams. Instead, big-block
buyers got a 427 stroked out to a full 4.00 inches and 454 cid. Two versions
were listed, one real, the other not. The former, RPO LS5, offered hydraulic
lifters, 10.25:1 compression, single four-barrel carb, 390 bhp at 4,800 rpm, and
a massive 500 pounds-feet of torque. Listed but never officially sold was RPO
LS7, with aluminum heads, mechanical lifters, 11.25:1 compression, a
higher-lift cam, and transistorized ignition. Depending on the source, output
was given at either 460 or 465 bhp. Sports Car Graphic tested an LS7 Corvette
and reported a standing quarter-mile of 13.8 seconds at 108 mph.
Rear-deck vents eliminated the need for door vents in the 1970 Corvette.
Like the previous year's enlarged small-block engine, a bigger big-block was offered in response to stricter emissions requirements. Also like the 350, the 454 produced less power per cubic inch than its predecessor, but a lower peak power speed gave it somewhat more torque, and thus more flexibility, at lower rpm. Road & Track tried an LS5 with an automatic and obtained 7.0 seconds for the 0-60-mph run, a 15.0-second quarter-mile at 93 mph, and a top speed of 144 mph. On the down side, testers found the suspension suffered from both excessive harshness over irregular surfaces and a certain floatiness at speed.
Not that these criticisms mattered much, because 1970 would mark the end for big-inch, big-power Corvettes in the traditional mold. Besides skyrocketing insurance rates and fast-falling demand for sporty cars, Chevy's top performance machines were doomed by GM president Ed Cole's desire to eliminate low-volume options. He also dictated that all engines be retuned to run on 91-octane fuel, anticipating the need for catalytic converters to meet ever-tightening emissions limits.
Learn about other Corvettes in this generation:
Looking for more information on Corvettes and other cars? See:
- Muscle Cars: Get information on more than 100 tough-guy rides.