Corvette Glossary Of Terms – D

c3 corvette

Corvette Glossary Of Terms



DeLorean, John Z.

January 6, 1925 – March 19, 2005) was an American engineer and executive in the U.S. automobile industry, most notably with General Motors, and founder of the DeLorean Motor Company.

He was best known for developing the Pontiac GTO muscle car, the Pontiac Firebird, Pontiac Grand Prix, and the DeLorean DMC-12 sports car, which was later featured in the 1985 film Back to the Future, and for his high profile 1982 arrest on charges of drug trafficking. The alleged drug trafficking was supposedly an attempt to raise funds for his struggling company, which declared bankruptcy that same year. He successfully defended himself against the drug trafficking charges, showing that his alleged involvement was a result of entrapment by federal agents. Corvsport Page References: 1970 Overview

Doug Nash “4+3” Transmission

A 4-speed manual coupled to an automatic overdrive on the top three gears. This unusual transmission was a synergy that allowed Corvette to keep a stout 4 speed, but add an overdrive. Corvsport Page References: C4 Overview1984 Overview, 1985 Overview, 1986 Overview1987 Overview, 1988 Overview.

Drag coefficient

A common metric in automotive design, where designers strive to achieve a low coefficient of drag. Minimizing drag is done to improve fuel efficiency at highway speeds, where aerodynamic effects represent a substantial fraction of the energy needed to keep the car moving.  Indeed, aerodynamic drag increases as the square of speed. Aerodynamics are also of increasing concern to truck designers, where a lower drag coefficient translates directly into lower fuel costs.

About 60% of the power required to cruise at highway speeds is used to overcome air drag, and this increases very quickly at high speed. Therefore, a vehicle with better aerodynamics will be more fuel efficient.

Reducing drag is also a factor in sports car design, where fuel efficiency is less of a factor, but where low drag helps a car achieve a high top speed.  However, there are other important aspects of aerodynamics that affect cars designed for high speed, including racing cars.  Notably, it is important to minimize lift, hence increasing down force, to avoid the car becoming airborne. Increasing the downforce pushes the car down onto the race track—allowing higher cornering speed.  It is also important to maximize aerodynamic stability: some racing cars have tested well at particular “attack angles”, yet performed catastrophically, i.e. flipping over, when hitting a bump or experiencing turbulence from other vehicles.   For best cornering and racing performance, as required in Formula One cars, down force and stability are crucial and these cars must attempt to maximize down force and maintain stability while attempting to minimize the overall Cd value.

The average modern automobile achieves a drag coefficient of between 0.30 and 0.35. SUVs, with their typically boxy shapes and larger frontal area, typically achieve a Cd of 0.35–0.45. A very gently inclined windshield gives a lower drag coefficient but has safety disadvantages, including reduced driver visibility. Certain cars can achieve figures of 0.25–0.30, although sometimes designers deliberately increase drag to reduce lift. Drag Coefficient content courtesy of Wikipedia. Corvsport Page References: C4 Overview


“Dyno” for short, is a device for measuring force, moment of force (torque), or power. For example, the power produced by an engine, motor or other rotating prime mover can be calculated by simultaneously measuring torque and rotational speed (RPM).

No Comment

Leave a reply

Your email address will not be published. Required fields are marked *