“The vehicle dynamics are spot on… the car behaves like a real racecar.”

Adam Burrows
2007 IMSA Continental Tire Sports Car Challenge Street Tuner Class Champion

Vehicle Modeling


Most racing video games, as well as the handful of software packages that could be considered racing simulations, have progressed to the point where the cars look real. The question is: Do they feel real? Realistic driving dynamics start with accurate data. That is why iRacing.com works closely with major auto manufacturers and race car constructors to gather exact masses and dimensions for vehicle components, whether output directly from CAD data, collected through three-dimensional laser scanning, or physically disassembling the vehicle to weigh and measure parts of the chassis, suspension and driveline.

But in the same way that a race car is not just a collection of parts, an accurate simulation is not just an assembly of data. Both are active and dynamic. Thanks to the iRacing.com physics engine and tire model, that data comes alive. It is no longer just a graphical representation of a stock car, formula car or sports car. It is now a complex set of interrelated mechanical systems influencing a myriad of ever-changing forces to control physical consequences. It feels real because, mathematically, it is real.



Physics Engine

A critical difference between past products and the hyper-accuracy achieved by iRacing.com is the sophistication of our physics engine.

A physics engine is a complex system of mathematical functions that replicates dynamic forces using data-driven calculations of action and reaction. It’s those instantaneous calculations that create iRacing.com’s three-dimensional sphere of existence, a virtual world with the same physical dynamics drivers experience in the real world.

With more than 20 racing-simulation releases (more than a dozen of which have garnered industry awards) to their credit, Dave Kaemmer and his team are among the world’s leading experts in the mapping of multi-body systems and the calculation of forces and their effects on motion.

Kaemmer’s relentless search for accuracy has led to the creation of a new, proprietary tire model. It replicates tire forces over a wide range of speeds and loads, adding an important dimension to the accuracy of the experience.