Page 197 - Wayne Carini's Guide to Affordable Classics

Is it now the best exotic car in the world? The best exotic car value?” Of course, there were some critiques, given all of the technology that McLellan’s team had brought to the new car. High among them was the “4+3” transmission that seemed to confuse drivers while delivering fuel economy that wasn’t all that much better than the four-speed automatic. Fortunately, a switch was added at the last minute that allowed the driver to turn it off. It was replaced by a conventional six-speed, sourced from ZF, in 1989.
Shortly after launch, it was time to put the Corvette into a scrum with its main competitors, such as the 944, 928, 308 and 300ZX. Road & Track’s early comparo with the C4’s European rivals found it still lacking: “The Corvette is an excellent car, among the best in the world” they concluded, “but against the cars in this test it lost several small battles of degree.” In fairness, the 308 and the 928 were priced nearly twice as high (the Corvette’s was $25,201 as tested), with only the 944 costing less, reinforcing the Corvette’s continued role as a tremendous value in the sports car world.
At launch, Chevrolet made it no secret that an engine upgrade was waiting in the wings, with the port-fuel-injected L98 engine replacing the throttle-body L83 for the C4’s second model year. Boosting output from 205 horsepower to 230 and torque from 290 foot-pounds to an impressive 330, the L98 also increased fuel economy by about ten percent. In 1986, the C4 coupe was rejoined by a convertible version, previously dropped from the lineup in 1976. Palmer’s team clearly had the convertible in mind from the start since it looked like such a natural addition to the product line. Priced at a $5,000 premium, it would account for about a third of Corvette sales. Optional for both the coupe and the convertible starting in 1987 was the Z52 suspension package, which seemed a good compromise between the base chassis setup and the bone- cracking, track-ready Z51 option.
1990 LT5 engine was the heart of the ZR-1. Jointly designed between GM and Lotus, it was assembled by Mercury Marine. Initial output of 375 horsepower was later increased to 405.
1986, whose renowned chassis and powertrain development capabilities opened the door for a significant upgrade to the C4. The first element of that journey was a new engine, the LT5, an aluminum-block V8 with the same bore centers as the L98, but with four overhead camshafts and 32 valves. A key element of its 375-horsepower output was a Lotus-designed air management system that widened the LT5’s power band by shutting off 8 of the 16 intake runners and their fuel injectors when the engine was at part-throttle but providing full power with a wide-open throttle.
Lotus also helped GM with the ZR-1’s chassis development, which started with massive, 11-inch-wide P315/35ZR-17 Goodyear Eagle Gatorbacks specially made for the rear of the C4, along with larger ventilated disc brakes. Other chassis innovations included a low-tire-pressure warning system as well as Bosch ABS and a Bilstein-developed adjustable suspension system adapted by Lotus from the Porsche 959. The system allowed for six damping settings in each of the three driving modes – Touring, Sport, and
From the start of the C4, and perhaps with a bit of insecurity
from press reviews that seemed unwilling to place the still-raffish
Corvette on par its European counterparts, Chevrolet believed
that increasing performance – both from the engine side as
well as even the chassis – was a key element in closing the gap.
Furthering that cause was GM’s acquisition of Group Lotus in Performance – with 14 total steps.
Chevrolet Corvette C4
A convertible Corvette rejoined the lineup for 1986 after being dropped in 1975 and was selected to pace that year’s Indy 500. All 7,315 1986 convertibles were considered Pace Car replicas.
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