Friday, September 18, 2009

Car Development in Racing

The challenge for each Indy Car Team is the same every year. Design and develop a race car that is safe, durable, and competitive in different racing conditions. Durability is required to complete the sixteen race schedule. In addition, cars must meet the demands of four different types of racing circuits, each course requiring a different aerodynamic and mechanical setup.

    Street: A narrow, temporary course ranging from 1.6 to 2.1 miles in length, with tight turns and a long straightaway. The Long Beach circuit (lap record 108.198 mph), tests the durability of the gearbox, braking system and low speed acceleration.
    Road: Laguna Seca Raceway (lap record 112.296 mph), is an example of a road course with hills. A road course is a wide open track that ranges in length from 1.9 to 4 miles. It has both slow and high speed corners and wide enough for passing. The suspension system, downhill braking and power are stressed on this type of course.
    Short Oval: Phoenix International Raceway (lap record 172.804 mph), is a one mile, long oval track. Short straightaways and banked turns are characteristics of this type of track. The short oval tests the suspension and aerodynamic setup of the car.
    Speedway: The speedway is an oval track with banked turns and long straightaways. The one lap record at the Michigan International Speedway (2 mile oval), is 234.275 mph. At Indianapolis (2.5 mile oval), the record is 232.618 mph. High, sustained speed requires aerodynamic efficiency.
The job of the team engineer is to prepare a competitive, safe car that can be adjusted quickly. Alan Mertens, Galles-Kraco car builder and race engineer says, "You spend the whole year chasing a moving target, but that's the definition of development of motor racing, it doesn't stand still very long." Feedback is provided by onboard telemetry, driver input, and mechanical failure. Information gained from an accident is also used to develop stronger, safer cars. Currently, the Indy Cars are considered to be the safest race cars in the world. Championship Auto Racing Teams (CART) is the governing body which sets safety rules and regulations for Indy Car World Series competition. CART is also responsible for organization of events and the car and engine specifications. A technical inspection is required for each car before racing to insure all rules are observed. 1994 Indy Car Specifications:
  • Chasis:
      length= 190" to 195"
      height= 32"
      width= 78.5"
      weight= 1550 lbs. Weight distribution 45% front and 55% in rear.
      rear wing height(Speedway)= 32"
      rear wing height (Oval/Road)= 36"
  • Engines:
      Turbocharged 4-cycle overhead camshaft with a maximum of 8 cylinders with 4 valves per cylinder. Illmor, Chevy, Ford and Honda reflect these specifications. These engines produce 750-800 horsepower at 12,800 rpms with a top speed of 240 mph. Car performance = 0-60 mph in 2 seconds and 0-100 mph in 4 seconds.
  • Fuel:
      Valvoline methanol is required. Each fuel tank can hold a maximum of 40 gallons of fuel and each car must have a minimum fuel efficiency of 1.8 miles per gallon. Methanol is used for safety reasons. It is not as explosive as gasoline. To minimize refueling hazards (1.1m mpeg movie) each entry must have a three-man refueling team. In addition, shutoff valves are required at both ends of the fueling hose.
  • Tires:
      Each team is allocated 28 tires per car per race, (200 miles), or sixty tires per car in 500 mile events. The wheels are cast magnesium 15" in diameter and 10"-14" in width. Heating of the tires is prohibited. Tire heating equipment is costly, and places a financial strain on teams seeking sponsorship. This CART regulation helps maintain a competitive balance in the series.
  • Chasis Construction:
      The chasis is constructed to afford maximum protection to the driver. Carbon fiber, aluminum or a combination of both may be used to build the chassis. All new designs must undergo primary and secondary impact testing.
Saftey rules and regulations have challenged engineers to become more inventive as the cars have become more complex. This has forced teams to concentrate on the total aerodynamic package of the race car. Bobby Rahal (Rahal/Hogan Racing) explains, "When something is designed, you must take into account the discipline that it's being used for and how you'll enhance that. The chassis and aerodynamics are inseparably linked. There's no question about it." Reduction in engine size is a good example. The 1993 Chevy Indy V8/C is a much more compact, streamlined version of the older, Chevy V8/A. The size of the engine has been reduced, to limit drag on the car. The net effect improves the aerodynamics of the car, and results in improved car performance. Team designers consider aerodynamic efficiency to be the most important element in developing a competitive race car.

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