Daunt
MLG Pro
So as we get more and more into making and tweaking our own setups I thought it wise to share basic fundamental knowledge of how a race car works, each component, to get a better understanding of how to set the car up. With this, you can really understand what might need to be tweaked in car and really understand, when you move something 1 or 2 clicks, is really happening.
I'm taking a lot from a couple books in racecraft I've read, namely "Ultimate Speed Secrets: The Complete Guide to High-performance and Race Driving" from Ross Bentley as well as "Going Faster! Mastering the Art of Race Driving" by Carl Lopez and Danny Sullivan.
Part 1: Suspension Basics
So rather than start off with something like aerodynamics and such, I wanted to start with a part of the car that was well-known at a macro level, but when it comes down to the individual parts and what happens through each turn, it is difficult to understand. Getting to know the suspension better is I think just as important as knowing what wing angle does and gear ratios, if not more important.
This particular guide I just would like to go over the different suspension parts and what options a driver would have over changing them. The next one I'll go into greater detail on how tweaking them affects driving at different speeds, and weight transfers, etc. For now, this is just a fundamentals guide for the different suspension parts.
Camber
Camber is the tilt of the wheel as seen from in front of the car, looking head on at the nose. So if a wheel is inclined at the top towards the center, which would give it an inward lean, it has negative camber. The opposite, an outward lean is positive camber.
The goal is to always have the tire's contact patch to be as large as possible, because obviously more contact means more grip. To really understand how this affects the car, you have to think about what happens when you take a corner at high speed.
When you turn left at high speed, the outside tires, the rightside tires in this case, lean outward (right). Now those outside tires bear most of the weight (just minor touching upon weight transfer for now) so they're doing most of the work. If you had no camber at all (so no lean inside nor out), those outside tires would now be leaning right, giving it positive camber. Likewise, your inside tires, which aren't doing as much of the work, are leaning towards the outside (right) but since it is leaning towards the inside of the car, they're going on negative camber.
The bigger issue is the tire that is doing most of the work, the rightside tires, are now leaning and therefor not getting as much contact with the pavement as possible. Now with a setup that had a resting camber of -.2, that might help offset that major lean in those corners. The goal is to get 0 camber when at maximum cornering, which will obviously vary depending on many things, starting with the track.
Caster
Caster is pretty straightforward. Caster is what gives the steering wheel it's self-centering tendency. A higher positive number means the wheel will center easier, which can be a desirable effect, but the drawback to this is turning gets to be more challenging. It takes more effort with more positive camber, which will give you heavy steering, so it is a compromise.
As mentioned, this is a positive number and negative caster is not used. The number is the inclination of the kingpin from full upright position. If you view the tire from the side, the inclination is towards the back of the car. So with a higher positive number, the pin tilts further back to the rear.
Toe
Viewed from above, toe describes which way the wheels are pointing. Toe-in is when the wheels are pointed in towards each other, where the front of the tires are closer to each other than than rear of the tires. Toe-out is the opposite.
Toe is an important part of the suspension system and determines straightline stability and initial turn-in characteristics. To get that better turn in for chicane-heavy tracks, this can be a great tool in helping squeeze a bit more time out.
Ride Height
Pretty self-explanatory of what ride height is: the distance from the ground to the lowest part of the car. Usually this is different between the front and back and this difference is called the rake. Adjusting the ride height is usually done to affect the car's rake as this is what truly affects the handling. So lowering the car .5" in both the front and rear doesn't change the rake at all so this wouldn't drastically affect how the car handles.
I say drastically because it will affect it. The lower the car, the better the aerodynamics and better handling, as a lower center of gravity is advantageous in turning. So this means you'll want to run the car as low as possible yet avoid bottoming out / running out of suspension travel.
Spring Rate
The spring rate is extremely important. It is the amount of force it takes to deflect a spring at a given amount. A softer spring rate allows the car to handle bumps, curbs and other undulations better, but a stiffer spring rate will keep the car from bottoming out when hitting a bump. So there's certainly a compromise here.
A lot of things go into setting the spring rate, like driver preference/style, the track, downforce of the car, etc. Generally you'd want the softest possible springs in the rear to help maximize traction on the rear tires, and tweak the setup from there to help deal with bumps and bottoming out.
Anti-Roll Bar
ARBs (sometimes wrongly called Sway Bars) exist to prevent / resist a vehicles tendency to roll (lean) to the outside during a turn.
Shock Rate
The shock rate refers to how well the car can absorb bounces and bumps throughout the pavement. This is done via shocks (or dampeners). Through this setting, you can not only change how the car handles bumps and reacts to them, but change other handling characteristics, like steering responsiveness. Changing spring rate has an affect on shock rate so the two are almost intertwined and must be given thorough consideration when testing.
Conclusion
Hopefully this gives you a really good starting point on the suspension system. The last part of which I wanted to go into tires and how everything might affect them, but I think it might be better to move it to the next guide, which will consist of tires, balance and weight distribution.
[HR][/HR]
Next Guide:
Tires, Balance & Weight Distribution
I'm taking a lot from a couple books in racecraft I've read, namely "Ultimate Speed Secrets: The Complete Guide to High-performance and Race Driving" from Ross Bentley as well as "Going Faster! Mastering the Art of Race Driving" by Carl Lopez and Danny Sullivan.
Part 1: Suspension Basics
So rather than start off with something like aerodynamics and such, I wanted to start with a part of the car that was well-known at a macro level, but when it comes down to the individual parts and what happens through each turn, it is difficult to understand. Getting to know the suspension better is I think just as important as knowing what wing angle does and gear ratios, if not more important.
This particular guide I just would like to go over the different suspension parts and what options a driver would have over changing them. The next one I'll go into greater detail on how tweaking them affects driving at different speeds, and weight transfers, etc. For now, this is just a fundamentals guide for the different suspension parts.
Camber
Camber is the tilt of the wheel as seen from in front of the car, looking head on at the nose. So if a wheel is inclined at the top towards the center, which would give it an inward lean, it has negative camber. The opposite, an outward lean is positive camber.
The goal is to always have the tire's contact patch to be as large as possible, because obviously more contact means more grip. To really understand how this affects the car, you have to think about what happens when you take a corner at high speed.
When you turn left at high speed, the outside tires, the rightside tires in this case, lean outward (right). Now those outside tires bear most of the weight (just minor touching upon weight transfer for now) so they're doing most of the work. If you had no camber at all (so no lean inside nor out), those outside tires would now be leaning right, giving it positive camber. Likewise, your inside tires, which aren't doing as much of the work, are leaning towards the outside (right) but since it is leaning towards the inside of the car, they're going on negative camber.
The bigger issue is the tire that is doing most of the work, the rightside tires, are now leaning and therefor not getting as much contact with the pavement as possible. Now with a setup that had a resting camber of -.2, that might help offset that major lean in those corners. The goal is to get 0 camber when at maximum cornering, which will obviously vary depending on many things, starting with the track.
Caster
Caster is pretty straightforward. Caster is what gives the steering wheel it's self-centering tendency. A higher positive number means the wheel will center easier, which can be a desirable effect, but the drawback to this is turning gets to be more challenging. It takes more effort with more positive camber, which will give you heavy steering, so it is a compromise.
As mentioned, this is a positive number and negative caster is not used. The number is the inclination of the kingpin from full upright position. If you view the tire from the side, the inclination is towards the back of the car. So with a higher positive number, the pin tilts further back to the rear.
Toe
Viewed from above, toe describes which way the wheels are pointing. Toe-in is when the wheels are pointed in towards each other, where the front of the tires are closer to each other than than rear of the tires. Toe-out is the opposite.
Toe is an important part of the suspension system and determines straightline stability and initial turn-in characteristics. To get that better turn in for chicane-heavy tracks, this can be a great tool in helping squeeze a bit more time out.
Ride Height
Pretty self-explanatory of what ride height is: the distance from the ground to the lowest part of the car. Usually this is different between the front and back and this difference is called the rake. Adjusting the ride height is usually done to affect the car's rake as this is what truly affects the handling. So lowering the car .5" in both the front and rear doesn't change the rake at all so this wouldn't drastically affect how the car handles.
I say drastically because it will affect it. The lower the car, the better the aerodynamics and better handling, as a lower center of gravity is advantageous in turning. So this means you'll want to run the car as low as possible yet avoid bottoming out / running out of suspension travel.
Spring Rate
The spring rate is extremely important. It is the amount of force it takes to deflect a spring at a given amount. A softer spring rate allows the car to handle bumps, curbs and other undulations better, but a stiffer spring rate will keep the car from bottoming out when hitting a bump. So there's certainly a compromise here.
A lot of things go into setting the spring rate, like driver preference/style, the track, downforce of the car, etc. Generally you'd want the softest possible springs in the rear to help maximize traction on the rear tires, and tweak the setup from there to help deal with bumps and bottoming out.
Anti-Roll Bar
ARBs (sometimes wrongly called Sway Bars) exist to prevent / resist a vehicles tendency to roll (lean) to the outside during a turn.
So to increase grip on the front (lessen understeer) you can try softening the front or stiffening the rear. Likewise, to increase rear grip (lessen oversteer) you can soften the rear or stiffen the front.Ross Bentley said:
Shock Rate
The shock rate refers to how well the car can absorb bounces and bumps throughout the pavement. This is done via shocks (or dampeners). Through this setting, you can not only change how the car handles bumps and reacts to them, but change other handling characteristics, like steering responsiveness. Changing spring rate has an affect on shock rate so the two are almost intertwined and must be given thorough consideration when testing.
Conclusion
Hopefully this gives you a really good starting point on the suspension system. The last part of which I wanted to go into tires and how everything might affect them, but I think it might be better to move it to the next guide, which will consist of tires, balance and weight distribution.
[HR][/HR]
Next Guide:
Tires, Balance & Weight Distribution
Last edited:
