Fuel; Gasoline Octane; Gasoline Specifications - Chevrolet 2003 Corvette Owner's Manual

Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle.
Gasoline Octane
Use premium unleaded gasoline with a posted octane of
91 or higher for best performance. You may also use
middle grade or regular unleaded gasoline rated at
87 octane or higher, but your vehicle's acceleration may
be slightly reduced. If the octane is less than 87, you
may get a heavy knocking noise when you drive. If this
occurs, use a gasoline rated at 87 octane or higher
as soon as possible. Otherwise, you might damage
your engine.
Gasoline Specifications
It is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers Association for better
vehicle performance and engine protection. Gasoline
meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasoline.
In Canada, look for the
"Auto Makers' Choice"
label on the pump.
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