C4 Chevrolet Corvettes - Generation-Four Spotter's Guide

Things You Can And Can't See In '84-'96 Corvettes

Andy Bolig Jan 5, 2010 0 Comment(s)
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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.

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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.

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What You See: The big news of 1985 was the switch to Tuned Port Injection for the engine. Having individual injectors for each cylinder gave much more control over the fuel trim of the engine; the tuned-length runners helped boost torque to 40 lb-ft, and horsepower increased from 205 to 230. This shaved almost a second off the previous year's quarter-mile times at the track. Also, the air was regulated by a single throttle body (no more equalizing throttle bodies) and the amount of air fed into the engine was measured by a Mass Air Flow meter (MAF). This helped increase fuel mileage because a 14.7:1 air-fuel mixture was easier to maintain.

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.

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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.

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What You See: This was the first year for the B2K option, also known as the Callaway Corvette engine, shown in photo.

What You Don't See: This was the first year for a roller camshaft and lifters inside the engine.

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What You See: Since there were no Corvettes produced on the 30th anniversary, GM decided to celebrate the 35th Anniversary Edition. "White" is the best way to describe one of these special edition coupes-white on the wheels, exterior, interior, steering wheel, beltline molding, and seats. Picture a white sheet of paper in an Alaskan snowstorm. Also, Chevrolet produced 56 street-legal Corvettes for the SCCA Corvette Challenge Series.

What You Don't See: There were several changes to the chassis of the '88 Corvette. Larger brakes were added to the Z51 suspension-optioned cars, and all '88 Corvettes got new dual-piston calipers up front and upgraded rear calipers that used the brake pads for the emergency brake rather than an internal brake-shoe assembly.


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