Crutches are born in the pits...
Crutches are born in the pits as racers try to help each other with their chassis problems. Smart racers rely on solid theory to support chassis changes, not monkey-see, monkey-do thinking.
You're hammering around the racetrack in your race car and it's just not handling. You feel like it's tight getting into the corner, which prompts you to turn the front wheels in, but the car slides up toward the wall as you negotiate the entrance to the middle of the corner. You have tried a few changes but nothing seems to help.
At a loss as to how to correct the problem, you walk around the pits seeking some wisdom from fellow racers. They throw out suggestions like, "Bolt 50 pounds of lead on the rear bumper," "bolt a tie-down shock on the left rear," or the classic, "increase the stagger between the rear tires." You might try one of these or all of them. You might even have some success at getting more balance in the car upon entry into the corner. But what you don't know is that these are all "crutches" that racers think correct a problem but actually just mask it enough to fool them.
Because of what these crutches do to the overall performance of the car, they hold cars or drivers back from improving their performance. Some examples of crutches are driving styles (throwing the car into a corner to loosen it up), hanging weight off the rear of the vehicle, a super-stiff right front spring, a longer right side wheelbase, rear steer to the right, tons of brake bias, and more. Do these sound familiar? They probably do because most racers use them.
If you want a great example...
If you want a great example of a tight or pushing race car, check out car #5 trying to avoid the wall. The front wheels are turned hard to the left, yet the car is still pointed toward the outside wall.
This story is the kickoff to a regular section in Circle Track about these mythical suspension and chassis fixes we call crutches. We're going to debunk many methods racers use on a daily basis supposedly to go faster around the racetrack. While most of these crutches will mask a problem enough to get around the track, they aren't the best solutions because they limit the overall performance of the vehicle. If you truly want to win, read these articles with an open mind and figure out how to incorporate the optimal solutions for your car to go faster, instead of relying on the monkey-see, monkey-do crutch fixes all the other racers are using.
We will call on many sources for useful information but rely heavily on Bob Bolles, the mastermind behind the Chassis R&D software and a real student of great suspension and chassis knowledge. He gets to ask some of the best racers in the circle track world the "stupid" questions and learns something every day because of it. We like his view on racing knowledge "The worst thing you can do is decide you know it all. I don't believe there is a way to know everything about making a car as fast as possible, but there are basic principles the quick race cars operate with. I have been able to clarify what some of these are from working with many winning racers. When someone brings a new idea to me, I ask as many questions as possible, weigh the results against my previous knowledge, and try my version of that technology on the race track. It's critical to understand how a change affected the car. Usually, that understanding is the hardest thing to achieve."
A loose race car will do what...
A loose race car will do what #15 is doing here-point toward the infield as the rear end slides out from under the car. The driver has a lot to do with how the car looks and drives on the track, which is why driver crutches are important to talk about.
It's important to define what is meant when racers say their car is "handling" well. Just so everyone is on the same page, "handling" in the case of a circle track race car means that as a driver, you can drive the car down into the corner without it being loose (this would cause the car to point toward the infield) or tight (also called pushing, which would point the car toward the outside wall-with wide eyes!). Both of these conditions limit your corner speed, which slows your straightaway speed, which makes for slow lap times. Since we all want quick lap times and fast straightaway and corner speeds, we want a car that's balanced between tight and loose, a car that is neutral through the corners. A neutral car that is set up correctly (no crutches) will be affected less by changing track conditions than a car that has been crutched to get neutral.
The three main areas where a race car is prone to have these problems are entry to the turn, through the middle of the turn, and exit from the turn.