Change has always been a factor for Corvettes. Being Chevrolet's showcase vehicle, some of the newest and most technologically advanced additions are often bolted to a Corvette first. The changes to the C4, when introduced in 1984, were distinct technological improvements in the structure and design of the vehicle. Throughout the car's production life, the General made changes, constantly improving upon a platform that launched with rave reviews. Today, this gives the prospective '84-'96 Corvette owner a bevy of options to suit their needs, wants, and financial availabilities.
What You See:The first obvious item is the carryover of the Cross-Fire engine. GM realized that performance and fuel economy meant having fuel control. Cross-Fire was an early attempt at controlling the V-8's fuel diet and, while it helped, it still didn't give enough control since there were two injectors for eight cylinders.
Besides the obvious changes made when Chevrolet introduced the C4 to the public, there was also a change in the mindset of those responsible for making the C4 a reality. Chief Engineer Dave McLellan and a handful of fellow decision-makers determined that a change was necessary, if not mandatory. Like the '53 Corvettes, criticism was forming that Corvette needed performance to match its performance image. Due to the growing concern for clean air and fuel mileage, performance was placed on the back shelf while all of the auto manufacturers were scrambling to meet ever-increasing government standards. Performance paid the price from the squeaky-clean wheel of emissions, limiting the '81 Corvette to only 195 net horsepower from its 350ci V-8, the same horsepower rating as the first 265ci V-8's gross rating in 1955!
What You Don't See:In an attempt to provide fuel mileage that met government standards and performance that met buyers' standards, GM also carried over the 700-R4 automatic from the '82 Corvette. New was the 4+3 manual transmission. Calling it a manual transmission is a bit of a misnomer because the front portion is basically a four-speed transmission with an overdrive unit mounted behind it that operated on the top three gears. GM was on the verge of losing its production source for transmissions, so joining with Doug Nash on these overdriven standard transmissions bridged the gap until something better was designed. These transmissions can be found in any standard-equipped Corvette from '84-'88.
Despite these winds of change at Chevrolet, tests were still proceeding on how to satisfy the greens keepers while bringing back the very thing that made Corvette an American icon: performance. While horsepower figures are a major portion of performance, horsepower is not the only element in the equation, especially if you are limited by fuel-mileage requirements. The engineers and designers knew this and began with a completely new mindset toward technology, utilizing new materials not available in prior generations of Corvettes. Before the C4, no new Corvette program had been approved by GM in over 20 years. The time had come.
Dave McLellan reports in his book, Corvette From The Inside, that the benchmark year for horsepower was 1970 with Corvette enjoying LT-1 small-blocks and LS5 big-blocks. While 370 and 390 hp levels were not going to happen overnight, it set a standard to target.
On the other side of the performance coin, the new car had to handle. The goal was 1 g of lateral acceleration, a lofty number usually achieved by only the most serious racing engineers. This necessitated a much wider, high-cornering-stiffness tire. Dave explains that steering changes of just one degree produce over 350 pounds of cornering force per tire, half again the cornering stiffness of a normal passenger-car tire. Therefore, keeping the tire squarely planted to the road was important, and the C4 was designed to be stiff by using stiff springs and heavy rollbars fore and aft. While the early C4s have been criticized for having a harsh ride, most enthusiast drivers know why. Dave and his crew were to meet their intended goal of 1 g, and, most of all, they did it in a production car.
Due to the extensive design and performance targets, the introduction of the C4, which was intended as an '83 model, was delayed a year, with no official Corvettes produced that year. All the Corvettes produced in 1983 were certified as '84s regardless of the actual delivery date. From there, it was a 12-year parade that was to become the fourth-generation "C4" Corvette.
Let's take a look at some contributions and significant changes that happened to Corvette through the C4 years, and the effect they had on Corvettes to follow.
1983
This is where it all started. While you can forget about ever owning one, you can see a real '83 Corvette at the National Corvette Museum (www.corvettemuseum.com). This is the only '83 known to exist today. It is the foundation that all other C4s were built upon. | 
What You Don't See:
Along with added control of the fuel, the '85 Corvette's computer was upgraded to better control engine performance. The suspension harshness issue was addressed, netting a better ride. | 
1986
What You See:
Convertibles were back! Corvette was pacing the Indy 500, so what kind of pace car would it be if it weren't a convertible? Also, with the introduction of the convertible came aluminum heads for Corvette. Originally, only the convertibles had them but it wouldn't be long before all Corvettes became light-headed.
What You Don't See:
Another advancement for the C4 was the introduction of ABS (antilock braking system), making the car significantly safer. This was also the first year for VATS (vehicle anti-theft system). Note the little pellet on the stem of your ignition key. It's actually a resistor that makes contact inside the ignition to let the computer know it's OK to start the car. Also, the caster was changed in the front-end alignment from 3.8 to 6 degrees. This helps keep the car more stable straight-line and prevents wander while driving. |