INDYCAR has announced that all engines for the IZOD IndyCar Series from 2014 forward will be equipped with twin Borg-Warner turbochargers. After Lotus dropped out of competition due to a problem-filled 2012, returning engine manufacturer Chevrolet squared dual turbochargers against Honda's single, and dominated the season. Next year should show better performance and a more level playing field.
IndyCar engines represent remarkable feats of engineering and experience. These 2.2 liter (135.25 cu in) turbocharged V6 engines weighing a mere 114 kg (250 lbs) might be an appropriate size for pushing along a mid-sized sedan, but pump out about 650 horsepower at up to 12,000 rpm. A combination of direct and indirect fuel injection allows these tiny engines to swallow the enormous amount of fuel needed to achieve such power.
Normal turbo boost is 21.75 psi for these mini-brutes, with a passing option allowing a temporary (15 to 20 seconds, depending on the track) increase to 23.2 psi. Ten such boosts are allowed during a race, after which the capability is self-terminated. It isn't yet clear how much advantage the extra boost will deliver to these E85 powered thoroughbreds, but time will tell.
For most of the last decade, Honda has been providing the only IndyCar racing engine in the world, which automatically removed engine performance as a factor in these races. In 2012, Chevrolet reentered the game as a second source of IndyCar engines, however, it decided to use a dual turbo rather than Honda's single turbo. Both options fit within the rules and, while not a walkaway win, the Chevy engine took a clear first in 2012 and is on track for a repeat this year.
In response to the slightly imbalanced versions of the IndyCar 2.2 liter engines, the INDYCAR Engine Committee, in coordination with Honda and Chevrolet who are preparing to update their engines, has decided that only engines with dual turbochargers will be allowed starts for the 2014 season. As Borg-Warner supplies all the turbochargers for INDYCAR, this, together with the rules limiting boost, will help insure that the drivers are tested more strongly than their racecars during a race.
"In an effort for parity throughout the turbocharger range, mandating only a twin turbo system simplifies our efforts to ensure even closer competition," INDYCAR president of competition and operations Derrick Walker said. "Both manufacturers displayed a willingness to use a common turbo spec for 2014, so it made sense to mandate a twin turbocharger that maintains the performance we've come to expect while keeping the technology relevant to the automotive industry."
Source: INDYCAR
First "Chevrolet squared dual superchargers"
Then later "Chevrolet... it decided to use a dual turbo rather than Honda's single turbo"
Turbochargers are different than superchargers, where as superchargers derive their power to compress more air into the engine directly from the crank shaft turbos use the exhaust gases from the engine. Each have their benefits and draw backs. The supercharger provides air to the engine at low RPMs as it is physically connected to the drive shaft but this also causes more load to be running on the engine reducing power gained from the extra air. Turbocharges tend to provide more power in the high RPM range and suffer from something called turbo lag. Turbo lag occurs because the turbo is power by the exhaust gases which take moments to build up pressure. Turbo systems also cause more back pressure on the engine decreasing the advantage of more combustible air in the engine.
Back in the late 70's and through much of the 80's Renault's V6 turbocharged and twin turboed Formula 1 engines developed between 500 and 1200 bhp- from 1.5 litres!
So this Chevy engine hardly represents progress...
I would be much more interested in true stock car racing. The cars having to be identical the cars on the showroom floor, no additional safety equipment, options, or stripping. Just bare boned, base model econo-boxes. It would be all driver cheap cars and you can drive a car identical to the one your hero drove Sunday to work on Monday.
Alternatively limiting the rules to; 250cc maximum displacement engine. 3m-3.1m long, 1.7m-1.8m wide, 1m -1.1m tall. Four tires on the ground. 20liter maximum fuel capacity. 2tonne weight as handicapped with the cars dry except for the brake fluid. The same crash cage specifications as say Indycar.