| The Indy Racing League, better known as IRL, is | | | | The current generation chassis however, are |
| the sanctioning body of a predominantly American | | | | designed to accommodate the added |
| based open-wheel racing series. Its centerpiece is | | | | requirements of road racing. Drivers report that |
| the Indianapolis 500. The IRL is owned by Hulman | | | | the cars are particularly demanding to drive on |
| and Co., which also owns the Indianapolis Motor | | | | road courses, especially when compared to GP2 |
| Speedway complex. The IRL was founded in | | | | and Champ Car chassis. |
| 1994 by Tony George and began racing in 1996. | | | | Indy Racing League officials have confirmed that |
| It was created with a breakaway group of | | | | the series will continue to use the current batch |
| drivers from CART, which had sanctioned Indy | | | | of Dallara and Panoz chassis for the balance of |
| car racing since 1979, who incidentally, had broken | | | | this season (2006). Both manufacturers have |
| away from USAC. George blueprinted the IRL as | | | | served as chassis manufacturers with the |
| a lower-cost open-wheel alternative to CART, | | | | IndyCar Series since 1997 and their current |
| which had come to be technology-driven and | | | | three-year chassis suppliers' agreement was |
| dominated by a few wealthy multi-car teams, | | | | signed in 2003. The series currently has no |
| much like Formula One. Ironically, the IRL has | | | | confirmed chassis contracts for 2007. By the end |
| come full-circle and is much like the CART series | | | | of the 2006 season, all full-time teams were using |
| it sought to separate from. The IRL is, itself, | | | | Dallaras for oval races. |
| dominated by a few wealthy teams, mainly | | | | The Engines |
| consists of foreign-born drivers, and is a mix of | | | | Starting in 1997, IRL cars were powered by 4.0L |
| ovals and road/street courses. | | | | V8, methanol burning, production-based, |
| The IRL developed a consistent engine package | | | | normally-aspirated engines, produced by |
| and chassis rules which have produced some of | | | | Oldsmobile (under the Aurora label) and Nissan |
| the closest finishes in any racing series. Ironically, | | | | (badged as Infiniti). That engine formula was |
| the series is now dominated by many of the | | | | replaced by a 3.5L format for 2000, at which time |
| same wealthy multi-car teams that once | | | | the requirement for the block to be |
| dominated CART. | | | | production-based was dropped. This formula was |
| The series initially raced exclusively on oval tracks, | | | | used through 2003. In 2004, the displacement |
| as the league was founded partly in response to | | | | was further reduced to 3.0L, in an attempt to |
| the increasing prominence of road and street | | | | curb top speeds. In 2006, the series switched to |
| courses on the CART schedule. In 2005, the | | | | a new fuel blend. For one season, the cars would |
| series abandoned its unofficial ovals-only stance, | | | | burn a 90%/10% mixture of methanol and |
| and added three road/street course events | | | | ethanol. For 2007, the engines will utilize a 100% |
| (Watkins Glen, Infineon and St. Petersburg). For | | | | ethanol fuel, and displacement will be increased |
| 2007, two more road/street events (Mid-Ohio and | | | | back to 3.5 L. |
| Belle Isle) were added. | | | | Historically, Honda, Toyota and Chevrolet |
| In its inception, the series and George himself | | | | competed for the engine supply business. In a |
| were widely ridiculed by members of the media | | | | major development announced by Chevrolet on |
| and some CART competitors. The IRL's early | | | | November 4 2004, Chevrolet stated that it would |
| seasons consisted of sparse schedules, mostly | | | | be ending its IRL engine program effective with |
| unknown drivers, and novice-level teams, even in | | | | the end of the 2005 season, citing costs that |
| the Indy 500. Eventually the schedule expanded, | | | | exceeded value, according to then-GM Racing |
| and caliber of drivers improved. The IRL began to | | | | Director Doug Duchardt. "The investment did not |
| draw teams from CART starting in 2000, | | | | meet our objectives," he was quoted as saying. |
| contributing to the latter's bankruptcy in 2003. | | | | In November 2005, Toyota company officials |
| The League consists of two series, the premiere | | | | announced the company's withdrawal from |
| IndyCar Series (usually considered synonymous | | | | American open-wheel racing and the immediate |
| with the Indy Racing League) and the Indy Pro | | | | discontinuation of its IRL program. The company |
| Series, which is a developmental series. | | | | in the past stated a dissatisfaction with the |
| The Cars | | | | investment returns in the series, and at the same |
| IRL is not an open formula, but neither is it a | | | | time, Toyota Racing Development is preparing for |
| one-make or "spec" series. Instead, chassis and | | | | entry into the NASCAR Nextel Cup Series in |
| engine manufacturers apply to the League to | | | | 2007. This has left Honda as the sole engine |
| supply cars for three year cycles. Currently, | | | | supplier to the IRL through 2009. Whether this |
| Dallara and Panoz provide the chassis, while Honda | | | | constitutes a serious blow to the series or just |
| is the sole engine provider. A third chassis | | | | another change remains to be seen. |
| manufacturer, Falcon, once held the rights to | | | | Currently, IRL engines are rev-limited to 10,300 |
| produce a chassis for IRL events, but as no | | | | rpm and produce approximately 750 hp at that |
| orders were ever made, no Falcon IRL rolling | | | | revolution regime. The Honda HI5R engine is a |
| chassis were ever completed, and the company | | | | normally aspirated, fuel-injected, aluminum alloy |
| has since ceased to exist. Riley & Scott produced | | | | cylinder block V-8 with a displacement of 3.0 liters |
| IRL chassis from late 1997 to 2000. In the series' | | | | (183.1 in3). The valve train is a dual overhead |
| first season, 1996, old CART chassis were used. | | | | camshaft configuration with four valves per |
| Superficially, IRL cars closely resemble those of | | | | cylinder. The crankshaft is made of alloy steel, |
| other open-wheeled formula racing cars, with | | | | with five main bearing caps. The pistons are |
| front and rear wings and prominent airboxes. | | | | forged aluminum alloy, while the connecting rods |
| Originally, the cars were unique, being designed | | | | are machined alloy steel. The electronic engine |
| specifically for oval racing; for example, the oil and | | | | management system is supplied by Motorola, firing |
| cooling systems were asymmetrical to account | | | | a CDI ignition system. The engine lubrication is a |
| for the pull of liquids to the right side of the cars. | | | | dry sump type, cooled by a single water pump. |