Racing software has become highly sophisticated and useful. We shouldn't be afraid to use the computer to help our racing effort. Computers and software are only tools that help us make critical decisions about engine tuning and chassis setup.
Today, nearly 100 percent of the U.S. population either owns or has access to a computer. Even the older racers down on the farm are typing away, one finger at a time, to send e-mails and correspond with fellow racers on the many message boards available on the Internet. Advanced communication that spreads the knowledge of racing technology has never been faster or more helpful.
Over the past 20 years, companies have worked to develop software packages to help racers understand their cars and perform calculations and simulations to perfect setups and driving styles.
Some racers are skeptical of using racing software and dislike being told how to set up their cars. Chassis setup is a specialized task, and the process used is somewhat confidential. Knowledge is power, and keeping an open mind may lead to the discovery of small performance improvements. Remember, no racing software program will set up the car, but it will provide critical information to make decisions.
Every software package offers value to the racer. Just like books on racing, all offer helpful routines and information that will aid your effort. If a team bought all of the available software that related to its racing, the total cost would be less than what we might spend on tire testing over a year's time.
Let's take a look at the various software programs that are available and learn a little from the suppliers about how they can benefit your race team.
AutoWare Inc. is a distributor and developer of racing related software. It carries software from other developers such as Racing Innovations and Performance Trends, and "House Brand" programs specifically for circle track racing.
Front Suspension Geometry Pro
Just as the name implies, this is a comprehensive three-dimensional front suspension program. A unique feature of this software is the input screens that have actual photos of suspensions with the required measurements drawn on the photos. The software covers typical parameters such as roll centers and creates a computerized model on your screen. You can then run the suspension through its travel and watch the camber change, side scrub, bumpsteer, caster change, and more right on the screen. It includes graphs and suggestions for changes to your geometry.
Rear Suspension Geometry
This is a software package that addresses three-link suspensions and Late Model four-link (floater)-style rear suspensions. It has the same photographic input as the Front Suspension Geometry Pro software. It creates models on the screen and allows one-wheel bump, body roll, squat and lift motions, tracks pinion angle, fore/aft movement of the wheels, and, most importantly, axle steer for all of these motions.
Computerized Chassis Weights
A calculating machine! This software calculates everything from center of gravity to roll couple distribution. Motion ratios, roll centers, crossweight, and more are addressed. An extremely valuable function is the weight transfer calculations. The software is great for seeing how weight transfer is impacted by banking angle, spring changes, Panhard bar changes, etc.
Tire Temp Analyzer
A cool tool for asphalt racers. This program gives you suggestions for setup changes based on tire temperatures, rim temps, lap times, hot and cold pressures, corner weights, and more. Great when you get a brain freeze at the track and need a jump-start.
Chassis R&D Corporation is a company that has specialized in technology development related to circle track racing for the past 10 years. The company has produced two software packages that assist racers in the setup of their race cars.
Front Geometry Software
This is a two-dimensional program that accurately locates the front roll center in both static and dynamic positions, and calculates the control arm lengths and angles as well as camber changes after the car dives and rolls in the turns. The entire program code was developed and written by the company and addresses the most critical components related to front suspension dynamics.
A unique feature of this software is that it allows the user to redesign his or her race car. You can quickly change the arm angles and arm lengths by simply typing in new values. This allows you to make improvements to your car and see the results on the computer.
Chassis Setup Software
This software is the result of advanced research in race car dynamics and was designed to help the racer find the optimum base setup for specific tracks. The program is a much needed tool that will calculate the "balance" of the chassis for ideal weight distribution in the turns using a unique patented process. The user can quickly see how the front and rear of the car are working and match the efforts of both ends by making changes to the spring rates, roll center locations (front and rear), and weight distribution.
The result is a car that has both suspension systems in harmony and working together, which is what all race cars need. The necessary data for the calculation is easy to enter, and the process of finding the best setup is fast and accurate. When properly done, the results will show on the racetrack through not only added speed in the turns, but more consistency on long runs and throughout changing track conditions.
William C. Mitchell Software Mitchell's Racing by the Numbers suspension geometry programs have been used for 20 years by racing teams around the world. The latest program, WinGeo3, is available for the Windows operating system. It is a complete, three-dimensional suspension kinematic program for double A-arm, MacPherson strut, and a variety of solid axle suspensions, including three-link, four-link, and truck arm. Steering may be rack-and-pinion or drag link.
The user can manipulate the chassis in ride height, body roll, pitch angle, and steering input. WinGeo3 displays all of the suspension characteristics, including camber, toe, caster, kingpin, instant center, roll center, Ackermann, and side-view swing-arm (SVSA) values. The results are displayed on the screen as well as in tables or plots. The user can manipulate the chassis to specific positions or run through a range of values to mimic the movement of the car through a turn or to produce a bumpsteer curve.
Chassis position can be specified by ride and roll values, by spring or shock displacement, or by clearance values.
WinGeo3 can compare two or more suspensions. The suspension is displayed with solid-model graphics that aid visualization of the suspension. WinGeo3 also includes suspension tutorials that display the lines needed to calculate an instant center or roll center.
The Premier/Data version of WinGeo3 uses on-board data to specify the chassis position through shock displacement and steering input. This capability can animate suspension movement for a complete lap or at a specific position on the track.
An upcoming version will add a vehicle dynamics capability, allowing the user to specify springs and bars and calculate a steady-state solution for specified g-forces. This will allow the user to calculate dynamic wheel loads with a variety of springs and chassis settings.
The Racing by the Numbers series of programs also includes a gearing program, a brake calculator, and the Debrief3 data analysis program.
Performance Trends is a software company that has developed some innovative packages for understanding your car's setup and motor combinations. Here are the software programs that are most appropriate for the circle track racer.
Roll Center Calculator
This is a simple two-dimensional front suspension layout program. It calculates roll center position, camber change, and wheel rates from spring rates for double A-arm or MacPherson strut suspensions. It lets you move the suspension through dive and roll and watch the roll center move and the camber change.
Circle Track Analyzer
The Circle Track Analyzer is a complete vehicle and lap-time simulation program. It includes the roll center calculator as the front suspension screen, and also includes engine power curve, vehicle, rear suspension, and track screens. From this information, it predicts lap times; on-track roll; dive; dynamic corner weights; lateral/longitudinal and vertical g's; engine rpm range; optimum gear ratio; and much more. It has several built-in utility screens to calculate spring rate, weight percentages, and even "virtual scales" to let you know how much to jack a spring to get the desired crossweight.
Suspension Analyzer
This program deals with the suspension only. However, it is a complete three-dimensional program for both front and rear suspensions. It lets you do steering inputs such as bumpsteer and Ackermann, antidive, caster change, rear roll steer, pinion angle change, antisquat, front-to-rear roll couple, and more. Other "adjust" and "optimize" options show the effects of shimming the upper arms or changing ride heights, or find settings for minimum bump steer, roll center height change, and much more.
DataMite Data Logger
This product is an electronics and sensor package that records what is happening on the track. It can record various engine parameters, accelerations, shock travel, steering travel, wheel rpm, etc. From this information, it can calculate A/F ratio, tire slip, lap times, friction circle analysis, general dive and roll of the vehicle, brake/throttle/steering wheel position, and track location. When linked with Suspension Analyzer, it can also show exact dive, roll, steer, roll center location, camber, caster, Ackermann, squat, and rear roll steer at any location on the track.
Computerized Chassis Setup from Steve Smith Autosports calculates a baseline chassis setup for optimum racing performance. This screen shows a recommended starting setup for a 2,800-pound Sportsman car racing on a 11/43-mile slightly banked paved track. Included in the setup are spring rates, shocks, weight percentages, and crossweight. Computerized Chassis Setup also contains additional resources to compute many other functions. This function calculates the exact location of the front roll center.
Steve Smith AutoSports offers several computer programs that are quite useful for all short-track racers. All programs come on CD and are compatible with all Windows operating systems. Complete operating instructions are included with the programs.
Computerized Chassis Setup
This program calculates a baseline chassis setup for optimum racing performance. It specifies a starting setup for a competitor's particular race car and track. Weights and measurements from a race car are entered into the program, along with information about the type and size of the racetrack, type of tire, track banking, and so on. The program then specifies spring rates and shock absorbers for each corner, sway bar rate (if the car uses one), corner weights, weight percentages, and crossweight.
Computerized Chassis Setup also contains additional resources to compute minimum tire stagger, proper final gear ratio, front roll center, roll couple distribution, and front antidive. It also contains a program to calculate the spring rate of a coil spring, leaf spring, torsion bar (solid or hollow), aftermarket sway bar, and stock sway bar.
This program is useful for any racing vehicle running on a dirt or paved oval track-Street Stock, Sportsman, Late Model, Modified, Sprint Car, etc.
Race Driving Simulator
Race Driving Simulator teaches competitors how to develop the optimum racing line for quick lap times. By defining certain parameters, a line around a corner is generated and split times are read off the screen to compare different approaches to the corner.
Users can learn when to apex early or late, and when to use a diamond line. They can evaluate the trade-off between mid-corner speed and getting on the throttle early. The program helps drivers know when to sacrifice speed in order to get on the throttle sooner. Conversely, they can learn when to maximize corner speed at the expense of early throttle application. The simulator can even demonstrate when exit speed is over-rated.
Race Driving Simulator provides a study of how the car's capabilities-power, cornering, and braking-relate to racing line choice. Not only is this useful for lowering lap times, but it can also teach users how to alter their lines to pass an equal car, or how to set up a re-pass maneuver.
The Race Driving Simulator allows the user to explore different racing lines. A standard late apex line, wide in the entrance, allows a driver to get to the throttle sooner and make a late apex while accelerating out of the turn. Trail braking and following the inside edge of the track. This produces a line that is shorter and may be quicker, with a possibly higher exit speed. The combinations of driving lines, braking points, and throttle application are infinite with Race Driving Simulator. It allows the user to pick the decision points for braking, turn-in, and throttle application, then compare various lines to find the fastest combination.
The combinations of driving lines, braking points, and throttle application are infinite with this program. You can define a track sector, which includes the braking area, the turn (including turn radius and track width), and the exit. This program allows you to pick the decision points for braking, turn-in, and throttle application. Compare the resulting lines for time and speed, with a plot of speed and g-forces for any point in the turn. The Race Driving Simulator is a teaching tool for the serious racer, not a hand-eye coordination game. The program includes substantial built-in help pages. Race Driving Simulator applies to all rear-wheel-drive racing vehicles running on paved tracks.
TirePro Computer Program
Most racers are aware of the immense value of taking tire temperatures to analyze the handling of their race cars. But many don't understand how to interpret the data that can be derived from tire temperatures. Tire temperatures are one of the most crucial diagnostic tools available to race teams at all levels.
The TirePro program quickly and easily performs a detailed analysis of the temperature data, providing information on tire pressure, wheel camber, handling balance, crossweight, weight distribution, and stagger. The built-in analysis identifies chassis problems, then suggests specific chassis changes to improve handling. In the analysis window, the user can choose from individual graphical depictions of toe-in/out, tire pressures, rear stagger, crossweight, and handling.
TirePro from Steve Smith Autosports quickly and easily performs a detailed analysis of tire temperature data. Individual elements in the Analysis Results screen in the upper right-hand corner can be selected for analysis and chassis tuning suggestions. This screen shows wheel camber change suggestions. The program analyzes tire pressures and gives specific suggestions for pressure adjustment. This program also analyzes crossweight and gives specific suggestions for adjusting the chassis. Other screens analyze camber, toe, tire pressure, rear stagger, and overall vehicle handling, with specific chassis setup changes suggested in each section.
Each analysis suggests what settings need to be adjusted. As the racer goes through the analysis options, the recommendations include the order in which changes should be made. For example, the toe-out screen notes that camber should be adjusted prior to setting toe-out. This ordering of procedures is a valuable reminder to experienced racers and an important guide for rookies. (Do all the right things in the wrong order and you'll be chasing the setup for months.)
The screen for entering the tire temperature data has fields in which to identify the car, track, session (heats, qualifying, feature, etc.), and the weather, as well as a "tires" field where the brand, size, or hardness of the tires can be noted. TirePro allows the user to enter many sets of temperatures and save them for future reference or analysis. You can analyze current readings instantly or browse saved data sets to find previous situations similar to those you're facing, to see what did or did not help the car.
A nice feature is a searchable help section to make finding answers to questions fast and easy. The help features are accessible from virtually any part of TirePro. TirePro is useful for any race car running on a paved oval track, and for cars running on hard, dry dirt surfaces when tires build up adequate heat.
Conclusion There are many computer programs that will enhance your understanding of circle track race cars and provide critical information about your car that can help you make key decisions on chassis setup. Contact these companies and visit their Web sites to learn more about which ones are right for your racing program.
Editor's Note: This article was compiled by Bob Bolles, who founded Chassis R&D Corporation.
