What Are Those Weird Codes that Look Like G/A/F and D/A/G ?

To keep costs down, the IRL does not allow teams unlimited leeway in what equipment they can run. Chassis and engine designs have to be submitted and approved by the IRL before being declared legal for competition; therefore, which equipment a team chooses to buy becomes an important part of the team's strategy, and can tell the knowledgable fan much about the team's potential and competitiveness. There are three primary categories where teams have choices to make about which brand to buy. Each team can choose these three things:

The codes are a shorthand way of expressing what equipment a team is running; they are often referred to as the C/E/T codes. The first letter indicates the chassis choice, the second the engine, and the third the make of tires. The codes for the currently available choices in each category are:

Chassis:
D = Dallara
G = G-Force
R = Riley & Scott

Engine:
A = Oldsmobile Aurora
I = Nissan Infiniti

Tires:
F = Firestone
G = Goodyear

In race results from 1996, the IRL's first year of operation, you will see different codes for the "old cars". These are chassis and engines that were no longer legal for IRL competition, as of calendar year 1997:

Chassis:
L = Lola
R = Reynard

Engine:
B = Buick
F = Ford Cosworth
M = Menard
MI = Mercedes-Ilmor

Tires are the same as current.