IndyCar Series

For 1996–1997, the series was simply referred to as the Indy Racing League. For 1998–1999, the series garnered its first title sponsor, and was advertised as the Pep Boys Indy Racing League. In 2000, the series sold its naming rights to Internet search engine Northern Light, and the series was named the Indy Racing Northern Light Series.[2]

The name IndyCar Series was officially adopted beginning in 2003, as the series was now legally entitled to use it due to the expiration of a 1996 legal settlement with Championship Auto Racing Teams (CART). The series began to progressively downplay the former IRL name, changing its name to simply IndyCar for the 2008 season. The company was similarly renamed in 2011.

Izod signed a six-year deal to become the series title sponsor beginning on November 5, 2009 through 2014,[3] but the sponsonship was terminated at the end of the 2013 season.[4] In 2014, Verizon Communications became title sponsor of the series through 2018.[5] In January 2019, it was announced that Japanese communications company NTT would become title sponsor and official technology partner of the IndyCar Series.[6]

In the series' first season (1996), 1992 to 1995 model year CART chassis built by Lola and Reynard were used. The first new Indycar came into being in 1997. Tony George specified new technical rules for less expensive cars and production-based engines. The move effectively outlawed the CART chassis and turbocharged engines that had been the mainstay of the Indianapolis 500 since the late 1970s.

G-Force GF05 IRL car in which Juan Pablo Montoya won the 2000 Indianapolis 500.

Starting with the 2003 season, the series rules were changed to require chassis manufacturers to be approved by the league before they could build cars. Prior to that, any interested party could build a car, provided it met the rules and was made available to customers at the league-mandated price. In total, four manufacturers have built IndyCar chassis.

Dallara began producing Indycars for the 1997 season. The Dallara and G Force chassis were relatively evenly matched over their first few seasons, but eventually, the Dallara began to win more races. This caused more teams to switch to the Dallara, further increasing their success. As of 2017, a Dallara chassis has been used by 17 Indy 500 winners, although there have not been any competing manufacturers since 2008. Dallara was also tabbed to build the Firestone Indy Lights machines. After the withdrawal of factory support from Panoz Auto Development, they are the only supplier of new chassis.

The G Force chassis was introduced in 1997 and won the 1997 and 2000 Indy 500 races. In 2002, Élan Motorsport Technologies bought G Force, and the chassis was renamed "Panoz G Force", and then shortened to "Panoz" in 2005. In 2003 a new model was introduced, and it won the Indy 500 in 2003–2004 and finished second in 2005. It fell out of favor starting in 2006, and by then, only one had finished in the top ten at Indy. Little factory support was given to IndyCar teams by Panoz after that point, as they had concentrated on their DP01 chassis for the rival Champ Car World Series. By 2008, only one Panoz saw track time, an aborted second-weekend effort at Indy, that resulted in Phil Giebler being injured in a practice crash.

A Panoz GF09 Indycar Series chassis driven by Jaques Lazier during practice for the 2007 Indianapolis 500.

Riley & Scott produced IndyCar chassis from 1997 to 2000. Their initial effort, the Mark V, was introduced late in the 1997 season, severely limiting its potential market. It also proved to be uncompetitive. After Riley & Scott was purchased by Reynard, an all-new model, the Mark VII, was introduced for the 2000 season. It won in Phoenix, the second race of the season (driven by Buddy Lazier), but was off the pace at Indy and was quickly dropped by its teams.

Falcon Cars were founded by Michael Kranefuss and Ken Anderson in 2002 as the third approved chassis supplier for the 2003 season. One rolling chassis was completed and shown, but it was never fitted with a working engine and never ran. No orders were ever filled. Superficially, IndyCar machines closely resemble those of other open-wheeled formula racing cars, with front and rear wings and prominent airboxes. Originally, the cars were unique, being designed specifically for oval racing; for example, the oil and cooling systems were asymmetrical to account for the pull of liquids to the right side of the cars. Later cars were designed to accommodate the added requirements of road racing.

Dallara IR05 Indycar chassis driven by Scott Sharp at the 2007 Bombardier Learjet 550 at Texas Motor Speedway.

Because of a schedule conflict, the Champ Car World Series spec Panoz DP01, with a Cosworth engine, was run in an IndyCar Series points event in the 2008 Toyota Grand Prix of Long Beach.

2012 DW12 chassis with the Speedway configuration driven by J. R. Hildebrand during practice for the 2012 Indianapolis 500. This initial version of the DW12 would be utilized during the 2012–2014 seasons.

In 2010, IndyCar announced that it would officially adopt a single-make chassis formula, beginning in 2012 among a selection of proposals from interested parties, and set up the ICONIC (Innovative, Competitive, Open-Wheel, New, Industry-Relevant, Cost-Effective) Advisory Committee to make a final recommendation.[7] Proposals were submitted and announced by BAT Engineering, Dallara, Lola, Swift, as well as the radical DeltaWing design that was penned by Ben Bowlby and financed by Chip Ganassi.

On July 2010, IndyCar announced that Dallara had won the contract to remain as the series' single chassis supplier.[8] In 2012 the series adopted the Dallara IR-12 chassis[9] as a cost control method, and IndyCar negotiated a price of $349,000 per chassis.[10] The new specification also improved safety, the most obvious feature being the partial enclosure around the rear wheels, which acts to prevent cars ramping up over another vehicle's back end. This chassis was intended to support multiple aerodynamic kits, but introduction of these was delayed until 2015, with teams citing costs.[11]

After the events of the 2011 IZOD IndyCar World Championships the chassis was nicknamed DW12 in honor of Dan Wheldon.[12]

2017 DW12 chassis driven by Mikhail Aleshin during Carb Day before the 2017 Indianapolis 500. This was driven with the Honda version of the Separate Manufacture Aerokits that were used for the 2015–2017 seasons.

In 2015, teams began running aero kits developed by their engine manufacturers as a first-ever Dallara DW12 facelift. The kits, while increasing speeds and offering a clear distinction between the two manufacturers, did lead to significant cost increases. Further, Chevrolet's aero kit was the more dominant with Honda only able to mount a competitive charge on ovals due to having slightly better engine power. While Honda was able to make gains in 2016, after two years of development the kits were frozen for 2017, and starting in 2018 all cars ran the same aero package again. To further help reduce costs, IndyCar allowed teams to shop for competitively priced non-safety-related parts such as brakes instead of mandating parts from specific suppliers.[13]

IndyCar had hoped to set a new speed record at the Indianapolis Motor Speedway by 2016 with the introduction of aero kits and the development work associated with them. However, after a series of safety concerns during practice for the 2015 Indianapolis 500 with the Chevrolet aero kit package, this did not come about.[14]

The 2017 season was the third and final year contested with the Chevrolet and Honda aero kits outfitted to the Dallara DW12 chassis. Beginning in 2018, all DW12 Safety Cell chassis was fitted with a universal bodywork kit. Digital renderings for the common bodywork kit, referred to as the 'IR18' car, were released in early May 2017 as a second facelift of Dallara DW12. The car was officially unveiled in late July, and the universal aero kit became known as the UAK18 bodywork.

The IR18 chassis in its Road Course configuration, driven by Sébastien Bourdais during the 2018 Kohler Grand Prix at Road America.

The bodywork is inspired by CART's 1990s and 2000s designs, with a more streamlined appearance. The redesigned aero kit reduces both aerodynamic downforce and team and manufacturer design development costs. The universal Aero Kit was designed without the wheel guards of the DW12 chassis, which were deemed ineffective and proved prone to breaking. The IR-18 also lacks an air inlet above the cockpit, a first for an IndyCar Series chassis (most Champ Car chassis had been designed that way). The new Aero Kit also has fewer small aerodynamic pieces that can become broken or dislodged, with the intent to reduce the amount of debris that ends up on the track and expenses from repairs. The "aeroscreen" cockpit protection was added in time for the 2020 season, and some minor modifications were eventually conducted to reduce the intense heat caused by stagnant air on the drivers.[15]

For the transmission gearboxes, all IndyCar Series cars currently use an electronically actuated AGS (Assisted Gearchange System) 6-speed semi-automatic sequential gearbox with an electro-pneumatically operated paddle-shift system and a pneumatic clutch with semi-automatic activation, supplied by Xtrac Limited since the 2008 season.[16] All current IndyCar transmissions use pneumatic actuation for the shifting and clutch, so the clutch is therefore only needed for launching the car from a standstill, and the clutch isn't required for gear shifting. From 1996 to 2007, all IndyCar Series cars used a hand-shifted 6-speed sequential manual transmission with a shift stick lever, supplied also by Xtrac since 2000 season until 2007. The clutches of all IndyCar Series cars are carbon with steel housing 3-plate clutch operated by foot-pedal in 1996–2011 later hand-paddle steering wheel clutch in 2012–present and provided by AP Racing. Mechanical limited-slip differentials are also allowed and constant velocity joint tripod driveshafts are also used. All IndyCar Series car drivetrains are currently rear mid-engine with rear-wheel-drive layout.

Since the formation of IndyCar Series in 1996, the brake package for the IndyCar Series was slimmer carbon brake rotors with 4-pot brake calipers and carbon pads on all-oval races until 2011. The thicker steel brake rotors with 6-pot brake calipers and carbon pads were introduced in 2005 for road and street course races for stronger braking while approaching sharper turns even hairpins. From 2012 onwards, IndyCar Series ditched the steel brake discs in favor of carbon brake rotors on all types of tracks but the caliper configuration remained the same as 1996–2011.

PFC currently supplying brake packages for all IndyCar Series cars since 2017 season (disc only) and later increased their involvement from the 2018 season (supplying the calipers and rest of other brake packages). Previously Brembo supplied the brake packages in 2012–2016 (full brake package), 2017 (caliper only), and Alcon in 2003–2011.

BBS and O.Z. Racing has been supplying forged wheels since 1996. The wheel rims for all IndyCar Series cars are made of aluminum alloy. The size of IndyCar Series wheel rims have been 10 in × 15 in (254 mm × 381 mm) on the front and 14 in × 15 in (356 mm × 381 mm) on the rear since 1996; this size will be used until at least the 2022 season. 18-inch wheel rims will be adopted if the Dallara DW12's successor comes out for the 2023 season onward.

Firestone is currently the tire supplier for the series since the 1996 season and later increased to sole tire supplier since 2000 season. Previously, Goodyear had also supplied tires from 1996 to 1999 for several teams, before withdrawing their support. The IndyCar Series runs the bespoke compounds since 1996 and re-profiled in 2003. The front tire sizes are 305/45-R15 (10.0/25.8-R15) and the rear tire sizes are 415/40-R15 (14.5/28.0-R15). The compounds and construction of IndyCar Series tires unique to each mounting position on the race car. For road/street events, there are unique primary and alternative specifications for dry conditions, along with specially designed rain tires for wet conditions. For oval racing, a single set of specifications is used, based upon the configuration and speed of the track, as well as having the right rear tire diameter constructed to be slightly larger than the left rear, (also known as stagger) to aid in high speed cornering.

The suspension of all IndyCar Series cars is double A-arm, pushrod, with third spring and anti-roll bar configuration multilink.

Cosworth CCW Mk2 steering wheel in the cockpit of Sage Karam's car.

Aeroscreen on Juan Pablo Montoya's car.

All NTT IndyCar Series cars use carbon-fiber shell driver's seats with 6-point safety restraints. The cars' steering wheels are designed by Cosworth with a system of buttons that allow the drivers to make adjustments to their cars mid-race. All IndyCar Series cars were equipped with Pi Research Sigma Wheel to Display data display units from 2001–2017 until they were replaced by Cosworth's Configurable Display Unit 4.3 display from 2018 onwards (although in 2018 some smaller low-budget IndyCar Series teams still utilized old Pi Research Sigma Wheel instead of new Cosworth Configurable Display Unit 4.3 due to cost reasons).

The cockpits of all IndyCar Series cars are still open but protected by zylon, a foot protection bulkhead, and cockpit padding.

From the 2020 season onwards, the IndyCar Series implemented a cockpit protection system. This consists of a combination of the Halo mandated in Formula One and a reinforced windscreen dubbed the "aeroscreen", provided by Red Bull Advanced Technologies, to lessen the probability of traumatic head injuries from flying debris.[17]

All IndyCar Series cars carry an Electronic Control Unit. Live telemetry is used only for television broadcasts, but the data can be recorded from the ECU to the computer if the car is in the garage tents and not on the track. Previously Motorola supplied IndyCar Series ECU in 2003–2009 for Honda-powered cars, also Denso supplied IndyCar Series ECU in 2003–2005 for Toyota-powered cars and also Zytek supplied IndyCar Series ECU in 2002–2005 for Chevrolet-powered cars.

Rearview mirrors for all IndyCar Series cars are fully mandated to easily enable viewing opponents behind.

At its inception, the IRL used methanol racing fuel, which had been the de facto standard in American open-wheel racing since the 1964 Indianapolis 500 Eddie Sachs - Dave MacDonald crash. Methanol had long provided a safer alternative to gasoline. It had a higher flash point, was easily extinguishable with water, and burned invisible. With the IRL's introduction of night races in 1997, the burning of methanol fuel was visible for the first time, seen with a light blue haze. With this in mind, in an effort to make it more visible in case of fire during daylight hours, additional mixtures were placed in the fuel. As a safety feature, the methanol would burn with color.

In 2005, the driver Paul Dana brought the sponsorship of the Ethanol Promotion and Information Council (EPIC) to his IndyCar team. EPIC is a consortium of ethanol producers that advocate the increased use of ethanol. EPIC was anxious to address public concerns of that era that ethanol use led to engine damage and poor performance when used in road cars. As a marketing effort, it was believed that sponsoring an IndyCar could be used as a tool to promote education and awareness of ethanol use and to curb the spread of erroneous information.

Dana was killed in a crash in 2006, but the IRL had already begun a transition to ethanol fuel. For the 2006 season the fuel was a 90%/10% mixture of methanol and ethanol. Starting in 2007, the league advertised "100% Fuel Grade Ethanol," the first competitive series to utilize renewable fuel. The mixture was actually 98% ethanol and 2% gasoline, provided by Lifeline Foods of Saint Joseph, Missouri. The additives satisfy the U.S. government's demand that the alcohol is unfit for human consumption and add visible color in case of fire. However, 2010 São Paulo Indy 300, held in Brazil –outside of the U.S. regulations– utilized a full E100 mixture, the first instance in the sport.

To compensate for the loss of power due to the use of ethanol, the displacement was increased back to 3.5 liters. Since ethanol gets better fuel mileage than methanol, the fuel tanks in the car were decreased.

Compared to methanol, human contact with the current ICS fuel is much less harsh, and the fumes much less irritating. The fumes are often compared with the sweet smell of apple cider or apple cobbler. Unlike methanol, ethanol is not caustic and does not cause chemical burns when it comes in contact with the skin. It also is less polluting when spilled compared to methanol.

In May 2010, Sunoco became the official fuel of the series starting in mid-2010 with an immediate effect, running through 2018.[18] For the 2012 season, the ethanol fuel blend rate was reduced to 85% blend in a reference of road car relevance. Speedway LLC took over as series official fuel supplier beginning from 2019 season onwards, but the E85 formula still retained until at 2022.

From 2023 onwards Shell USA (North American division of Shell plc) will supply 100% Ethanol-sourced fuel for the first time since 2011.

The fuel cell for all current IndyCar Series cars are made of rubber and are covered with a Kevlar-fitted blanket for extra protection in side impacts. Since 2012 the capacity has been 18.5 US gallons (70 litres). Previous capacities were 22 US gallons (83 litres) in 2007–2011, 30 US gallons (114 litres) in 2004–2006, and 35 US gallons (132 litres) in 1997–2003.

The initial 1996 IRL season, as well as the first two races of the 1996–97 season, featured engines with specifications leftover from the rival CART series competition. Those chassis/engine combinations were essentially under the same rules utilized by teams that participated in the 1995 Indianapolis 500, which was sanctioned by USAC. V-8 powerplants were allowed the typical 45 inHg (1.5 bar; 22.1 psi) of pressure boost. The Menard-Buick V6 engine used in 1996, however, was an updated powerplant from the 1995 version. In addition, the V-6 stock block engines (Buick-Menard) were allowed 55 inHg (1.9 bar; 27.0 psi) of boost at all races, instead of just at Indianapolis. During the CART era, V-6 stock blocks were only allowed 45 inHg (1.5 bar; 22.1 psi) at all races outside of Indy, which was a decided disadvantage and left the engine out of favor.

Ford-Cosworth reluctantly provided support to teams wishing to run their older-spec engines in the IRL, a major point of contention for CART management, to whom Ford-Cosworth was an official engine supplier. The Ilmor Mercedes V-8 engine, also a mainstay CART powerplant, was permitted, but the only time it was used as a one-off at the 1996 Indy 500 by Galles Racing.

Honda Indy V8 engine on the car

Starting in 1997, IRL cars were powered by 4.0-litre V8, four-stroke piston, Otto cycle methanol-burning, production prototype-based, naturally-aspirated internal combustion engines and electronic indirect multi-point port fuel injection, produced by General Motors (under the Oldsmobile Aurora label) and Nissan (badged as Infiniti). Per IRL rules, the engines sold for no more than $80,000 (with an exception of full-works IndyCar Series teams that usually received a free engines due to direct partnership with an each engine manufacturer), and were rev-limited to over 10,000 rpm and weighed up to 280 lb (127 kg) (excl. headers, clutch, ECU, spark box or filters).[19] They produced around 600–700 hp (450–520 kW).[19] These engines utilized 90° crankshafts, and while the engine blocks were to be production-based, they were not "stock blocks" like the Buick or Menard engines of the 1980s and 1990s. They were purpose-built racing engines.

The engine formula was changed with the 2000–2004 formula. The displacement was dropped down from 4.0 to 3.5 litres (244 to 214 cubic inches), and the requirement for the block to be production-based was dropped. The engines also switched to 180° crankshafts, and the rev limits were adjusted from time to time. These engines made 675 hp (503 kW), ran on 109-octane methanol racing fuel, and revved to 10,300 rpm, all while weighing only 280 lb (130 kg).[20] This formula was used through 2003.[21] In 2004, in the wake of several crashes including the fatal crash of Tony Renna and the severe crash of Kenny Bräck, the displacement was reduced to 3.0-liters using the existing engine blocks to curb top speeds (started from the 2004 Indianapolis 500).

Infiniti's engines, though reliable, were significantly down on power compared to the Auroras in 1997, leading many of the teams that had initially opted for the Infiniti to switch. By the end of the 1998 season, only a handful of low-budget teams were using the Infiniti. However, early in the 1999 season, Cheever Racing, a well-funded team, was brought on to develop the engine with team owner Eddie Cheever expanding the team to two cars and bringing on his brother Ross Cheever as a test driver. By 2000, the engine had improved markedly and Cheever captured the marque's first win at Pikes Peak International Raceway. However, despite the improved success, few teams made the switch to the Infiniti and the company left the series after the 2002 season to focus on powering the league's new Infiniti Pro Series (now Firestone Indy Lights).

As part of General Motors' discontinuance of the Oldsmobile name, the Olds engine was rebadged as the Chevrolet starting with the 2002 season.[22] However, the effort would lack in competitiveness against Toyota and Honda, which came to the IRL in 2003 from the rival CART series. In August 2003, Chevrolet announced to the public its "Gen IV" motor, a rebadged Cosworth motor for competition. At the time, Cosworth was owned by Ford. On November 4, 2004, Chevrolet stated that it would be ending its IRL engine program effective with the end of the 2005 season, citing costs that exceeded value, according to then GM Racing Director Doug Duchardt, "The investment did not meet our objectives."

Toyota won its first race in Miami, as well as the Indianapolis 500 and the series title. However, Toyota had just one podium in the last seven races of 2004, and only Penske Racing fielded competitive Toyota-powered cars in 2005, while Honda became the dominant engine manufacturer within the series. In November 2005, Toyota company officials announced the company's withdrawal from American open-wheel racing and the immediate discontinuation of its IRL program, coinciding with its entrance into NASCAR's Craftsman Truck Series in 2004, and its discontinuation of its IMSA program.

After Chevrolet and Toyota elected to shut down their IRL involvement after 2005 season (Chevrolet temporarily hiatus from IndyCar Series for six years while Toyota USA elected to focus on NASCAR involvement), Honda became the only standard spec-engine manufacturer in the IndyCar Series starting in 2006 and continued in that capacity through 2011 as it was announced by Indy Racing League president & chief operating officer Brian Barnhart and Honda Performance Development president Robert Clarke on December 15, 2005.[23][24] The IndyCar Series carried on with only one engine manufacturer in spite of the television agreement required at least two or three engine manufacturers to participate in the series to ensure future continuity. The Honda Indy V8 engine was partnered and co-developed by Ilmor, which is part owned by Roger Penske for tune-up, engine maintenance, arrangement and trackside support. The engine displacement was reverted from 3.0 to 3.5 litres (183 to 214 cubic inches) beginning from 2007 season. Leading IndyCar teams like Penske Racing, Andretti Green Racing, Chip Ganassi Racing, Rahal Letterman Racing and A. J. Foyt Enterprises received free engines from Honda due to direct works partnership but the rest of them were utilizing engine purchase payment system.

During that time, since the IndyCar Series had only one engine manufacturer, Honda focused on minimizing engine failure and minimizing costs instead of defeating rivals. As such, the engines were moderately de-tuned. The engines proved themselves to be quite durable — there had been no engine failures at Indy from 2006 to 2010, which also lowered the number of crashes. Most of the engines, including those used for the Indy 500, are used for multiple races and were intended to last 1,200 miles (1,931 kilometres) between rebuilds.[25] The Honda engines were only available via lease arrangement from Honda, which, for the 2010 full season, cost $935,000 U.S. per season, per car.[26]

IndyCar Series engines were rev-limited to 10,300 rpm and produce approximately 650 hp. A 'push-to-pass' system was intermitently adopted since the middle portion of the 2009 season, which increased the numbers to 10.500 rpm and 690 hp when employed. The valve train is a dual overhead camshaft configuration with four valves per cylinder. The fuel feed of Honda Indy V8 engine was an electronic indirect multipoint port fuel injection. The crankshaft is made of alloy steel, with five main bearing caps. The pistons are forged aluminum alloy, while the connecting rods are machined alloy steel. The electronic engine management system is supplied by Motorola, firing a CDI digital inductive ignition system. The engine lubrication is a dry-sump type, cooled by a single water pump. In 2009, Honda froze the Indy V8 engine development for the 2009–2011 seasons due to Honda focusing on a new third-generation V6 turbo engine for the 2012 season.

The current, third-generation IndyCar formula was introduced in 2012 including two new manufacturers, and marked the return of the IndyCar Series engine manufacturer competition war since the 2005 season. The engines are now fuel-efficient DOHC 2.2-liter twin-turbo V6 with four-stroke piston Otto cycle developing an estimated 550–750 hp depending on the level of boost used and no inter-cooling systems. They are limited to 12,000 rpm and weighed up to 248 lb (112 kg). Engines are currently supplied by Chevrolet and Honda.[27] Since the 2012 season, McLaren has supplied its TAG-400i engine control unit. The current engine fuel injector delivery now combines direct and electronic indirect injection which produces roughly 300 bar (4,351 psi) of rail pressure. No fuel flow restriction exists in the IndyCar Series engine configuration. Chevrolet returned to the series in 2012 to provide all-new, Ilmor developed and engineered, V6 twin-turbocharged engines after six-year hiatus while Honda still remain committed to the series also to provide all-new V6 single-turbocharged engines in the same year. Lotus Cars provided an engine developed by Judd in 2012, but left the series in 2013 after lack of interest from teams in running the underdeveloped and uncompetitive Lotus engine.[28] The push-to-pass overtake system was reintroduced during 2012 Honda Indy Toronto round and still being used currently that produced roughly 60 hp (45 kW) with a duration about 6–200 seconds of usage rechargeable (varies track shape). Porsche also expressed interest in joining the series as a third engine supplier in 2019. Ultimately Porsche backed out when IndyCar refused to allow them to field a hybrid powertrain. Coincidentally, IndyCar announced its plans for a hybrid powertrain one month later. Chevrolet was the first engine manufacturer to utilize the twin-turbocharged configuration alongside Lotus in 2012 while Honda was utilized the single-turbocharger in 2012–2013. Honda abandoned the single-turbocharged after 2013 in favor of twin-turbochargers from 2014 until the present.

Turbochargers were reintroduced from the start of 2012 season. The turbo configuration is currently twin-turbocharged that mandated since 2014 and producing the turbo boost level pressure range restricted to 1.3–1.6 bar (19–23 psi) depending on track shape. American turbocharger company BorgWarner Inc. currently supplies exclusive turbocharger kits including wastegate for all IndyCar Series cars from 2014 season onwards using an EFR7163 model in order to save costs. Previously a BorgWarner EFR9180 single turbo was used exclusively by Honda-powered cars while BorgWarner EFR6758 twin turbos were used exclusively by Chevrolet and Lotus (2012) powered cars. The turbochargers of all IndyCar Series engines are incorporated with intercoolers.

The 2024 season will see the displacement of the V6 twin-turbo engines increase from 2.2 to 2.4 L (134 to 146 cu in) and power increase from 550–700 to 900 hp (410–522 to 671 kW). hybrid systems will be introduced, consisting of a multi-phase motor, inverter, and battery that will create energy recovery from the car's braking system.[29]

Bosch (Chevrolet) and NGK (Honda) have provided spark plugs for all IndyCar Series cars since 2012. Previously NGK was an exclusive spark plugs supplier in 2006–2011 when Honda was the standard IndyCar Series engine supplier. Previously Denso also was a sparkplugs supplier in 2003–2005 for Toyota-powered cars.

The current IndyCar Series car top speed is approximately 235–240 mph (378–386 km/h) on the Indianapolis Motor Speedway oval layout only. On intermediate and long ovals the top speed is approximately 215–220 mph (346–354 km/h), and on road/street courses and short ovals, it is approximately 200–210 mph (322–338 km/h) depending on downforce setup.[30][31][32]

• Engine displacement: 4.0 L (244 cu in) DOHC V8
• Gearbox: 6-speed sequential manual transmission
• Weight: 1,590 lb (721 kg) including driver, fuel and all lubricants and coolants
• Power output: 700 hp (522 kW)
• Fuel: 100% Methanol
• Fuel capacity: 30 US gallons (114 litres)
• Fuel delivery: Fuel injection (electronic indirect ported multi-point)
• Aspiration: Naturally-aspirated
• Length: 192 in (4,877 mm) minimum on intermediate and long ovals; 196 in (4,978 mm) maximum on short ovals
• Width: 78.5 in (1,994 mm) (outside wheel rims); 77.5 in (1,968 mm) minimum (measured at the hub centerline)
• Wheelbase: 120 in (3,048 mm), plus or minus 2 in (50.8 mm) (118 to 122 in (2,997 to 3,099 mm))
• Steering: Variable-assisted manual, rack and pinion
• Tires: Firestone Firehawk and Goodyear Eagle radial dry slick for all tracks

• Engine displacement: 3.5 L (214 cu in) DOHC V8
• Gearbox: 6-speed sequential manual transmission
• Weight: 1,590 lb (721 kg) including driver, fuel and all lubricants and coolants
• Power output: 650 hp (485 kW)
• Fuel: 100% Methanol
• Fuel capacity: 30 US gallons (114 litres)
• Fuel delivery: Fuel injection (electronic indirect ported multi-point)
• Aspiration: Naturally-aspirated
• Length: 192 in (4,877 mm) minimum on intermediate and long ovals; 196 in (4,978 mm) maximum on short ovals
• Width: 78.5 in (1,994 mm) (outside wheel rims); 77.5 in (1,968 mm) minimum (measured at the hub centerline)
• Wheelbase: 120 in (3,048 mm), plus or minus 2 in (50.8 mm) (118 to 122 in (2,997 to 3,099 mm))
• Steering: Variable-assisted manual, rack and pinion
• Tires: Firestone Firehawk radial dry slick for all tracks

• Engine displacement: 3.5 L (214 cu in) DOHC V8
• Gearbox: 6-speed sequential manual transmission
• Weight: 1,565 lb (710 kg) including driver, fuel and all lubricants and coolants
• Power output: 650 hp (485 kW)
• Fuel: 100% Methanol
• Fuel capacity: 30 US gallons (114 litres)
• Fuel delivery: Fuel injection (electronic indirect ported multi-point)
• Aspiration: Naturally-aspirated
• Length: 192 in (4,877 mm) minimum on intermediate and long ovals; 196 in (4,978 mm) maximum on short ovals
• Width: 78.5 in (1,994 mm) (outside wheel rims); 77.5 in (1,968 mm) minimum (measured at the hub centerline)
• Wheelbase: 120 in (3,048 mm), plus or minus 2 in (50.8 mm) (118 to 122 in (2,997 to 3,099 mm))
• Steering: Variable-assisted manual, rack and pinion
• Tires: Firestone Firehawk radial dry slick for all tracks

• Engine displacement: 3.5 L (214 cu in) (first 3 races) later 3.0 L (183 cu in) (started from 2004 Indianapolis 500) DOHC V8
• Gearbox: 6-speed sequential manual transmission
• Weight: 1,565 lb (710 kg) on ovals; 1,640 lb (744 kg) on road and street courses (including driver, fuel and all lubricants and coolants) - started from 2005
• Power output: 650 hp (485 kW)
• Fuel: 100% Methanol
• Fuel capacity: 30 US gallons (114 litres)
• Fuel delivery: Fuel injection (electronic indirect ported multi-point)
• Aspiration: Naturally-aspirated
• Length: 192 in (4,877 mm) minimum on intermediate and long ovals; 196 in (4,978 mm) maximum on short ovals, road and street courses
• Width: 78.5 in (1,994 mm) (outside wheel rims); 77.5 in (1,968 mm) minimum (measured at the hub centerline)
• Wheelbase: 120 in (3,048 mm), plus or minus 2 in (50.8 mm) (118 to 122 in (2,997 to 3,099 mm))
• Steering: Variable-assisted manual, rack and pinion
• Tires: Firestone Firehawk radial dry slick for all tracks and treaded wet only for road/street courses if raining (introduced since 2005)

• Engine displacement: 3.0 L (183 cu in) DOHC V8 (supplied by Honda Performance Development)
• Gearbox: 6-speed sequential manual transmission
• Weight: 1,565 lb (710 kg) on ovals; 1,640 lb (744 kg) on road and street courses (including driver, fuel and all lubricants and coolants)
• Power output: 650 hp (485 kW)
• Fuel: EPIC 10% Ethanol + 90% Methanol
• Fuel capacity: 30 US gallons (114 litres)
• Fuel delivery: Fuel injection (electronic indirect ported multi-point)
• Aspiration: Naturally-aspirated
• Length: 192 in (4,877 mm) minimum on intermediate and long ovals; 196 in (4,978 mm) maximum on short ovals, road and street courses
• Width: 78.5 in (1,994 mm) (outside wheel rims); 77.5 in (1,968 mm) minimum (measured at the hub centerline)
• Wheelbase: 120 in (3,048 mm), plus or minus 2 in (50.8 mm) (118 to 122 in (2,997 to 3,099 mm))
• Steering: Variable-assisted manual, rack and pinion
• Tires: Firestone Firehawk radial dry slick for all tracks and treaded wet only for road/street courses if raining

• Engine displacement: 3.5 L (214 cu in) DOHC V8 (supplied by Honda Performance Development)
• Gearbox: 6-speed sequential manual transmission
• Weight: 1,565 lb (710 kg) on ovals; 1,640 lb (744 kg) on road and street courses (including driver, fuel and all lubricants and coolants)
• Power output: 650 hp (485 kW)
• Fuel: EPIC 98% Ethanol + 2% gasoline[33]
• Fuel capacity: 22 US gallons (83 litres)
• Fuel delivery: Fuel injection (electronic indirect ported multi-point)
• Aspiration: Naturally-aspirated
• Length: 192 in (4,877 mm) minimum on intermediate and long ovals; 196 in (4,978 mm) maximum on short ovals, road and street courses
• Width: 78.5 in (1,994 mm) (outside wheel rims); 77.5 in (1,968 mm) minimum (measured at the hub centerline)
• Wheelbase: 120 in (3,048 mm), plus or minus 2 in (50.8 mm) (118 to 122 in (2,997 to 3,099 mm))
• Steering: Variable-assisted manual, rack and pinion
• Tires: Firestone Firehawk radial dry slick for all tracks and treaded wet only for road/street courses if raining

• Engine displacement: 3.5 L (214 cu in) DOHC V8 (supplied by Honda Performance Development)
• Gearbox: 6-speed paddle-shift gearbox (semi-automatic)
• Weight: 1,565 lb (710 kg) on ovals; 1,640 lb (744 kg) on road and street courses (including driver, fuel and all lubricants and coolants)
• Power output: 650 hp (485 kW)
• Fuel: EPIC 98% Ethanol + 2% gasoline[33]
• Fuel capacity: 22 US gallons (83 litres)
• Fuel delivery: Fuel injection (electronic indirect ported multi-point)
• Aspiration: Naturally-aspirated
• Length: 192 in (4,877 mm) minimum on intermediate and long ovals; 196 in (4,978 mm) maximum on short ovals, road and street courses
• Width: 78.5 in (1,994 mm) (outside wheel rims); 77.5 in (1,968 mm) minimum (measured at the hub centerline)
• Wheelbase: 120 in (3,048 mm), plus or minus 2 in (50.8 mm) (118 to 122 in (2,997 to 3,099 mm))
• Steering: Variable-assisted manual, rack and pinion
• Tires: Firestone Firehawk radial dry slick for all tracks and treaded wet only for road/street courses if raining

• Engine displacement: 3.5 L (214 cu in) DOHC V8 (supplied by Honda Performance Development)
• Gearbox: 6-speed paddle-shift gearbox (semi-automatic)
• Weight: 1,565 lb (710 kg) on ovals; 1,640 lb (744 kg) on road and street courses (including driver, fuel and all lubricants and coolants)
• Power output: 650 + 20 hp (485 + 15 kW) including push-to-pass
• Fuel: 98% Ethanol + 2% gasoline
• Fuel capacity: 22 US gallons (83 litres)
• Fuel delivery: Fuel injection (electronic indirect ported multi-point)
• Aspiration: Naturally-aspirated
• Length: 192 in (4,877 mm) minimum on intermediate and long ovals; 196 in (4,978 mm) maximum on short ovals, road and street courses
• Width: 78.5 in (1,994 mm) (outside wheel rims); 77.5 in (1,968 mm) minimum (measured at the hub centerline)
• Wheelbase: 121.5–122 in (3,086–3,099 mm)
• Steering: Variable-assisted manual, rack and pinion
• Tires: Firestone Firehawk radial dry slick for all tracks and treaded wet only for road/street courses if raining

• Engine displacement: 3.5 L (214 cu in) DOHC V8 (supplied by Honda Performance Development)
• Gearbox: 6-speed paddle-shift gearbox (semi-automatic - must have reverse only for road/street courses)
• Weight: 1,565 lb (710 kg) on ovals; 1,640 lb (744 kg) on road and street courses (including driver, fuel and all lubricants and coolants)
• Power output: 650 + 40 hp (485 + 30 kW) including push-to-pass
• Fuel: Sunoco 98% Ethanol + 2% gasoline
• Fuel capacity: 22 US gallons (83 litres)
• Fuel delivery: Fuel injection (electronic indirect ported multi-point)
• Aspiration: Naturally-aspirated
• Length: 192 in (4,877 mm) minimum on intermediate and long ovals; 196 in (4,978 mm) maximum on short ovals, road and street courses
• Width: 78.5 in (1,994 mm) (outside wheel rims); 77.5 in (1,968 mm) minimum (measured at the hub centerline)
• Wheelbase: 121.5–122 in (3,086–3,099 mm)
• Steering: Variable-assisted manual, rack and pinion
• Tires: Firestone Firehawk radial dry slick for all tracks and treaded wet only for road/street courses if raining

• Engine displacement: 2.2 L (134 cu in) DOHC V6
• Gearbox: 6-speed paddle-shift gearbox (must have reverse)
• Weight: 1,580 lb (717 kg) on 1.5-mile speedways, superspeedways and Indianapolis 500; 1,610 lb (730 kg) on short ovals, road and street courses (including driver, fuel and all lubricants and coolants)
• Power output: Venue dependent 550–750 + 60 hp (410–559 + 45 kW) (push-to-pass)
• Fuel: Sunoco E85 Ethanol + 15% gasoline
• Fuel capacity: 18.5 US gallons (70 litres)
• Fuel delivery: Combination of direct and indirect injection that produced 300 bar (4,351 psi; 30,000 kPa; 225,019 Torr; 296 atm; 8,859 inHg) of maximum fuel system pressure
• Fuel-mass flow restrictor rate: Unlimited
• Aspiration: Single-turbocharged (Honda) and twin-turbocharged (Chevrolet and Lotus)
• Turbocharger: BorgWarner EFR9180 (single) and BorgWarner EFR6758 (twin)
• Turbo boost pressure (above atmosphere): 1.5 bar (21.8 psi; 150.0 kPa; 1,125.1 Torr; 1.5 atm; 44.3 inHg)
• Turbocharger spin rev limit: 116,000 rpm (EFR9180) and 153,900 rpm (EFR6758)
• Length: 203.94 in (5,180 mm) on road/street course and short ovals; 197.33 in (5,012 mm) on 1.5-mile intermediate ovals, superspeedway and Indianapolis 500
• Width: 78.5 in (1,994 mm) maximum; 77.5 in (1,968 mm) minimum (measured outside rim to rim); 79 in (2,007 mm) overall
• Wheelbase: 117.5–121.5 in (2,984–3,086 mm) adjustable
• Steering: Variable manual rack and pinion, no power assistance
• Tires: Firestone Firehawk radial dry slick for all tracks and treaded wet only for road/street courses if raining

• Engine displacement: 2.2 L (134 cu in) DOHC V6
• Gearbox: 6-speed paddle-shift gearbox (semi-automatic - must have reverse)
• Weight: 1,580 lb (717 kg) on 1.5-mile speedways, superspeedways and Indianapolis 500; 1,610 lb (730 kg) on short ovals, road and street courses (including driver, fuel and all lubricants and coolants)
• Power output: Venue dependent 550–750 + 60 hp (410–559 + 45 kW) (push-to-pass)
• Fuel: Sunoco E85 Ethanol + 15% gasoline
• Fuel capacity: 18.5 US gallons (70 litres)
• Fuel delivery: Combination of direct and indirect injection that produced 300 bar (4,351 psi; 30,000 kPa; 225,019 Torr; 296 atm; 8,859 inHg) of maximum fuel system pressure
• Fuel-mass flow restrictor rate: Unlimited
• Aspiration: Twin-turbocharged
• Turbocharger: BorgWarner EFR7163
• Turbo boost pressure (above atmosphere): 1.3 bar (18.9 psi; 130.0 kPa; 975.1 Torr; 1.3 atm) on superspeedways; 1.4 bar (20.3 psi; 140.0 kPa; 1,050.1 Torr; 1.4 atm) on Indianapolis 500 qualifying; 1.5 bar (21.8 psi; 150.0 kPa; 1,125.1 Torr; 1.5 atm; 44.3 inHg) on short ovals and road/street courses; 1.65 bar (23.9 psi; 165.0 kPa; 1,237.6 Torr; 1.6 atm; 48.7 inHg) push-to-pass
• Turbocharger spin rev limit: 150,600 rpm on superspeedways including Indianapolis Motor Speedway oval; 149,500 rpm on short ovals and road/street courses
• Length: 203.94 in (5,180 mm) on road/street course and short ovals; 197.33 in (5,012 mm) on 1.5-mile intermediate ovals, superspeedway and Indianapolis 500
• Width: 78.5 in (1,994 mm) maximum; 77.5 in (1,968 mm) minimum (measured outside rim to rim); 79 in (2,007 mm) overall
• Wheelbase: 117.5–121.5 in (2,984–3,086 mm) adjustable
• Steering: Variable manual rack and pinion, no power assistance[34]
• Tires: Firestone Firehawk radial dry slick for all tracks and treaded wet only for road/street courses if raining

Max Chilton during practice for the 2018 Grand Prix of Portland.

Takuma Sato during 2019 Indianapolis 500.

• Engine displacement: 2.2 L (134 cu in) DOHC V6
• Gearbox: 6-speed paddle-shift gearbox (semi-automatic - must have reverse)
• Weight: 1,590 lb (721 kg) on 1.5-mile speedways, superspeedways and Indianapolis 500; 1,620 lb (735 kg) on short ovals; 1,630 lb (739 kg) road and street courses (including driver, fuel and all lubricants and coolants)
• Power output: Venue dependent 550–750 + 60 hp (410–559 + 45 kW) (push-to-pass)
• Fuel: Sunoco (2018) later Speedway LLC (2019) E85 Ethanol + 15% gasoline
• Fuel capacity: 18.5 US gallons (70 litres)
• Fuel delivery: Combination of direct and indirect injection that produced 300 bar (4,351 psi; 30,000 kPa; 225,019 Torr; 296 atm; 8,859 inHg) of maximum fuel system pressure
• Fuel-mass flow restrictor rate: Unlimited
• Aspiration: Twin-turbocharged
• Turbocharger: BorgWarner EFR7163
• Turbo boost pressure (above atmosphere): 1.3 bar (18.85 psi; 130.00 kPa; 975.08 Torr; 1.28 atm; 38.39 inHg) on superspeedways; 1.4 bar (20.31 psi; 140.00 kPa; 1,050.09 Torr; 1.38 atm; 41.34 inHg) on Indianapolis 500 qualifying; 1.5 bar (21.76 psi; 150.00 kPa; 1,125.09 Torr; 1.48 atm; 44.29 inHg) on short ovals and road/street courses; 1.65 bar (23.93 psi; 165.00 kPa; 1,237.60 Torr; 1.63 atm; 48.72 inHg) push-to-pass
• Turbocharger spin rev limit: 150,600 rpm on superspeedways including Indianapolis Motor Speedway oval; 149,500 rpm on short ovals and road/street courses
• Length: 201.7 in (5,123 mm)
• Width: 75.5 in (1,918 mm) inches minimum (road/street), 75.75 in (1,924 mm) minimum (ovals), 76.5 in (1,943 mm) maximum (measured outside rim to rim)
• Wheelbase: 117.5–121.5 in (2,984–3,086 mm) adjustable
• Steering: Variable manual rack and pinion, no power assistance[34]
• Tires: Firestone Firehawk radial dry slick for all tracks and treaded wet only for road/street courses if raining

Hélio Castroneves during 2021 Indianapolis 500

• Engine displacement: 2.2 L (134 cu in) DOHC V6
• Gearbox: 6-speed paddle-shift gearbox (semi-automatic - must have reverse)
• Weight: 1,650 lb (748 kg) on 1.5-mile speedways, superspeedways and Indianapolis 500; 1,680 lb (762 kg) on short ovals; 1,690 lb (767 kg) road and street courses (including addition of aeroscreen + driver, fuel and all lubricants and coolants)
• Power output: Venue dependent 550–750 + 60 hp (410–559 + 45 kW) (push-to-pass)
• Fuel: Speedway LLC (2020–2022) E85 Ethanol + 15% gasoline (2020–2022) later Shell (2023 onwards) E100 Ethanol
• Fuel capacity: 18.5 US gallons (70 litres)
• Fuel delivery: Combination of direct and indirect injection that produces 300 bar (4,351 psi; 30,000 kPa; 225,019 Torr; 296 atm; 8,859 inHg) of maximum fuel system pressure
• Fuel-mass flow restrictor rate: Unlimited
• Aspiration: Twin-turbocharged
• Turbocharger: BorgWarner EFR7163
• Turbo boost pressure (above atmosphere): 1.3 bar (18.85 psi; 130.00 kPa; 975.08 Torr; 1.28 atm; 38.39 inHg) on superspeedways; 1.5 bar (21.76 psi; 150.00 kPa; 1,125.09 Torr; 1.48 atm; 44.29 inHg) on Indianapolis 500 qualifying; 1.5 bar (21.76 psi; 150.00 kPa; 1,125.09 Torr; 1.48 atm; 44.29 inHg) on short ovals and road/street courses; 1.65 bar (23.93 psi; 165.00 kPa; 1,237.60 Torr; 1.63 atm; 48.72 inHg) push-to-pass
• Turbocharger spin rev limit: 150,600 rpm on superspeedways including Indianapolis Motor Speedway oval; 149,500 rpm on short ovals and road/street courses
• Length: 201.7 in (5,123 mm)
• Width: 75.5 in (1,918 mm) inches minimum (road/street), 75.75 in (1,924 mm) minimum (ovals), 76.5 in (1,943 mm) maximum (measured outside rim to rim)
• Wheelbase: 117.5–121.5 in (2,984–3,086 mm) adjustable
• Steering: Variable manual rack and pinion, no power assistance[34]
• Tires: Firestone Firehawk radial dry slick for all tracks and treaded wet only for road/street courses if raining

Starting in 2010, the series began recognizing two sub-set championship trophies alongside the season championship. The two primary disciplines of IndyCar (ovals and road courses) were named after respective legends of the sport: A. J. Foyt and Mario Andretti, respectively. The discipline trophies were created as the series moved closer to a 50/50 split of oval and road races, and to encourage incentive for part-time entries – specifically, those that might prefer to compete in one discipline over the other.

This arrangement also creates a reasonable opportunity for a team to employ the services of two drivers for one season entry. A team could hire a specialist for ovals and a specialist for road/street courses, who combined would maintain the entry's total owner points but individually work towards their own separate disciplines.

Note that street courses are included as part of the road racing discipline. Since 2013, the individual discipline trophies have received markedly less fanfare.

Season	A. J. Foyt Oval Trophy	Mario Andretti Road Course Trophy
2010	Dario Franchitti	Will Power
2011	Scott Dixon	Will Power
2012	Ryan Hunter-Reay	Will Power
Season	A. J. Foyt Former Oval Trophy	Mario Andretti Former Road Course Trophy
2013	Hélio Castroneves	Scott Dixon
2014	Juan Pablo Montoya	Will Power
2015	Juan Pablo Montoya	Will Power
2016	Josef Newgarden	Simon Pagenaud
2017	Hélio Castroneves	Josef Newgarden
2018	Will Power	Scott Dixon
2019	Simon Pagenaud	Scott Dixon
2020	Scott Dixon	Josef Newgarden
2021	Pato O'Ward	Álex Palou
2022	Pato O'Ward	Will Power