GM RACING PRE-RACE ADVANCE--WATKINS GLEN

SIMULATION HELPS GM TEAMS SET BASELINE FOR CHASSIS SETUP

Watkins Glen offers specific challenges for teams used to turning left only

 

Watkins Glen, N.Y., Aug. 6, 2003 - Race teams use a variety of methods to determine setups for the tracks upon which they ply their trade. Chief among them is experience, because there is no substitute for having been there and done that. Oval tracks, as a rule, usually require the same sort of chassis tweaks, because they all offer left turns only. Throw in a track where you have both left and right turns, and all that goes out the window.

 

That's where GM Racing's Chassis and Aero Group comes into play.

 

It is possible, says engineer Dave McLain, to simulate a lap at Watkins Glen International via computer and pass that information along to GM Racing teams who want to use it. 

 

"We work on projects with the teams and team engineers," McLain explained. "Some of them are specific to short-term things, specific tracks, whereas others are more in R&D mode, where we're looking for things that might not show up on the race track for a while. I've spent some time working with teams on road courses, doing simulation work. A lot of it is trying to understand tradeoffs in different gear selections, trying to identify shift points given an engine's torque and horsepower curve that will minimize lap times."

 

Minimizing lap times is what it's all about in Winston Cup racing these days, especially on a road course. Turning left all day is one thing, but turning that around and turning right most of the day is quite another. Computer simulation, which is one of the buzzwords of the modern-day race team, helps in determining a baseline for GM Racing teams to use once they get to the Glen. "We can definitely simulate a lap around a place like Watkins Glen and come up with setup and gearing recommendations that really are the starting point for the teams to use," McLain said. 

 

McLain has been with the GM Racing group for about four years, and simulation is what he was brought in to do. One of his primary responsibilities is to help get GM Racing teams up to speed on the simulation technology available from General Motors. "I'm a one-man show, so I'm not trying to do simulations week in and week out," McLain said. "We've picked some teams and some tracks to work with to kind of show them the merits of simulation. Our ultimate goal is to get them self-sufficient. Some teams are, and some teams are at different levels as to how they are applying simulations. Our focus is to try and identify tools for them to ultimately use. As part of that we get involved in projects where we kind of show them what it can do."

 

Eddie Dickerson, who heads up the chassis shop at Hendrick Motorsports, said the simulation is a very useful tool for the teams to use. "It gives us a solid baseline for setup, and it is very helpful," said Dickerson. "We've been doing it with GM for six or seven years, and in the future, I can see us using it more and more. It is definitely the wave of the future."

 

Setting up a car for Watkins Glen is an exercise in unlearning what teams spend 34 of the 36 race weekends learning. The car, instead of being set up to turn left only, becomes more like your passenger car: that means it can turn both left and right equally well. "These are completely different cars than they use on the ovals," McLain explained. "They are straight up instead of offset, the bodies are straight up. A normal car is designed to turn left. The race car isn't designed to turn left only, so the cars don't have stagger in them at the road course. The suspension is straight up. It's a straight up car. The other big difference at the road course is shifting gears. There's a lot of compromise at the road course."

 

In your passenger car, weight distribution is as close to straight up as possible. It's the same for the race car on a road course. "On a road course, you want the weight toward the center of the car as much as you can so the car is quicker to respond to turning input," McLain supplied. "There's not a whole lot you can do there because of the rules for engine and fuel cell locations, but you try to put the weight toward the center of the car as much as you can."

 

All this jiggering around of weight, suspension points and neutral setup is to facilitate high-speed and low-speed corners linking various straightaways on a road course. It's a compromise to get the car set up to work well everywhere. "The road course is unique because you have different corners," McLain said. "You really have to find the balance in some corners and probably compromise in some to get through others. The corners that lead to high-speed straightaways are the ones you want to get off and have good exit speed leading to the straightaway to carry that speed down the length of the straightaway. You may have to sacrifice some of the corners in order to accomplish that."

 

Incidentally, aerodynamics plays a role here just as much as they do at every other track on the circuit. The lack of banking at Watkins Glen-and at New Hampshire, Indianapolis and Pocono-means that there is not as much vertical force being applied to the top of the tires. The tires, as any racer will tell you, are all that keep your car on the road. "Aero becomes an even bigger part, because you look at the total vertical force on the tire, without the banking effect, the aero becomes an even bigger percentage of what you do have." 

 

In the 20 NASCAR races run at the 2.45-mile Watkins Glen International course, former site of the U.S. round of the Formula One World Championship, GM Racing cars have won 14. Chevrolets have won nine of those 14, including five of the last six. Pontiac has won four and Buick one.