On the scope of builds in the history of this sim, 2021 iRacing Season 4 is a decent change for the AI aspects. New cars and tracks have been added, but on top of that, Online Multiplayer Hosted Racing now has the ability to add in AI drivers to the starting lineup. Other known content included the additions of the Ferrari 488 GT3 EVO to.
- Iracing Correct Camber Meaning
- Iracing Correct Camber Model
- Iracing Correct Camber Code
- Iracing Correct Camber Tool
In the last article, I talked about the uses of toe and how it affects both drivability and front-end dynamics. However, that is only one of the three basic geometric ways to move a tire on a race vehicle. Of the other two, camber is well-recognized, but for all intents and purposes, the least-understood of the three, caster, is sometimes the most overlooked about setups.
Everyone who has pushed a shopping cart understands caster. Caster wheels, when placed on heavy objects that need rolling, allow the object to maintain momentum in a straight line. In other words, once it gets going, it likes to keep going. Think of it as a way to love Newton’s First Law of Motion: an object in motion tends to stay in motion. Newton would’ve loved caster wheels.
- The first is a new three-part section on Basic Race Car Set-Up hosted by Grand-Am driver David Donohue and Jay O'Connell, Technical Director for Rahal Letter.
- The DD2 iRacing setting is near to driver version 346’s default, but not exact. Before finalizing on the setup of your wheel base, it’s advised to do a swift check on your shifter’s calibration. When this has been activated, a writ up at the right side of the button will lead you to your next process.
Caster helps the old lady push her three bags of cat litter through the grocery aisle without breaking a hip. It also allows me to move 55-gallon steel tanks of liquid nitrogen with two fingers. (Getting it started is a two-handed requirement.) However, what we know as caster wheels are just half the trees of the proverbial forest.
So what does caster do? Well, to understand why something works, it’s good to know how it works. Caster is a measurement of how far “pulled back” a wheel is from its center. It’s measured in the same degrees found on a circle, and the more the wheel is pulled back, the more degrees of caster that wheel has. Conversely, if you can pull a wheel back (+ caster), you can also push a wheel forward (- caster).
So how does that translate to what you feel? Think about what caster does to wheelbase. Positive caster shortens wheelbase, and negative caster lengthens wheelbase. Custom-chopped motorcycles have an extreme amount of negative caster because they lengthen the wheelbase from neutral. Ask anyone who drives a motorcycle, and they’ll tell you that the steering on these bikes is very, very sensitive and does not correct itself. However, on a shopping cart that has a lot of positive caster, if you turn the cart and let go suddenly, the wheels will correct the line of travel and allow the cart to more naturally travel in a straight line.
Shorter wheelbase cars can turn much easier. This is why if you look in the street stock pits at your local bullring, most of the cars are shorter wheelbase models, like vintage Camaros. The late ’70s model Camaro was (and still is) an extremely popular racing car simply because its wheelbase is the shortest allowed by many local rules. It’s so ubiquitious around the country that iRacing based its street stock on this car model!
So wouldn’t it serve best to pull both wheels back to maximum caster and shorten the wheelbase? Well, yes and no. Caster feels different to a driver than what a setup may show, and most of it has to do with the camber and toe settings. However, what most drivers feel when they say “caster” is actually a “caster split.” Think of it this way: maximum caster split would be the LF hub pulled back as far as possible, and the RF hub pushed forward as far as possible, causing the shortest wheelbase on the left side, and the longest wheelbase on the right side. So what does this do to the feel of a car in the corner? Well, try it out in a test session. You’re going to find the left side of the car is going to “pull” the chassis in the corner nicely, but it’s also going to turn a little too nicely off the corner as well as the front tires fight each other to gain grip!
Caster split is a mean devil. It can cause massive headaches with setups, but it can also be just the thing you need to make your setup even better.
Usually, drivers have a feel for a certain caster setting, and leave their setups alone in this regard. Dale Earnhardt, Sr. was known to prefer a higher caster split, and I’m sure there are top-tier drivers from all backgrounds who prefer different caster settings. Although caster does make an impact upon dynamic toe and camber, it is often adjusted according to driver feel.
Iracing Correct Camber Meaning
So then why do nearly all circle-track setups have a LF wheel at negative caster and a RF wheel at positive caster? It has to do with the self-straightening tendencies of positive caster and self-turning tendencies of negative caster. As the car is cornering and the tires are under stress, the LF will want to turn itself MORE (because of the increased toe-out) and the RF will want to straighten itself (toe-in). If you can see this in your mind, the caster is actually working to toe the front-end around the corner by itself!
Google play store apk for android 2.3.5. So, in short:
Iracing Correct Camber Model
Positive caster in both front wheels will make the car slightly unresponsive in the steering, and will heed less to setup changes (less dynamic toe-out).
Negative caster in both front wheels will make the car feel responsive, more “touchy” and sensitive to track changes and tire temperatures (more dynamic toe-in).
Positive caster split (LF more + than RF) will make the car turn-in easily, and turn-out easily. Bob marley family tree. Drivers complain of too much caster split as having no control with the steering wheel, and the car wants to fight itself into and out of each left-turn.
Negative caster split (LF more – than RF) will make the car turn less easily in the corners, but drivers will feel like they have significantly more control with the wheel; less “slop” in the steering. The dynamic toe will also be helping the chassis to turn throughout all parts of the corner.
Understanding caster is just one more trick to have in the bag when it comes to finding that extra tenth or that comfort level in the setup. After all, confidence makes you faster, right?
You may also like..
Recommended
Force Dynamics Dallara iRacing Grand Prix Championship Race Preview: Monza
Recommended
Recommended
Berryman Wins First Career Force Dynamics Dallara iRacing Grand Prix Race at Interlagos
Iracing Correct Camber Code
Recommended
Robertson Wins Second iRacing Rallycross World Championship Round in Atlanta in Two Years
Static ride height is one of the key setup adjustments, and also one of the easiest to get right. For example, for many cars converting a qualifying setup into a race setup (or vice versa) only means adjusting fuel and the static ride height. In this article we’ll explain what ride height entails, how you can adjust it, and how it affects other setup adjustment.
![Iracing Correct Camber Iracing Correct Camber](https://i.redd.it/w10442cptft41.png)
Static versus dynamic ride heights
Ride height (measured in mm or in) defines how far off the ground the chassis sits. Static ride height is what you configure in the garage. Dynamic ride height is the actual ground clearance at any moment in time as the car goes around the track. The dynamic ride height changes throughout a lap, for instance when a car goes over a curbstone, or when downforce compresses the springs. The dynamic ride heights also changes throughout a stint, for as the fuel burns off and the tank empties, the car becomes lighter and therefore ‘rises’.
Ride height (measured in mm or in) defines how far off the ground the chassis sits. Static ride height is what you configure in the garage. Dynamic ride height is the actual ground clearance at any moment in time as the car goes around the track. The dynamic ride height changes throughout a lap, for instance when a car goes over a curbstone, or when downforce compresses the springs. The dynamic ride heights also changes throughout a stint, for as the fuel burns off and the tank empties, the car becomes lighter and therefore ‘rises’.
Depending on the location of the ride height sensor (e.g. splitter, tire, etc) and its vertical offset, the ride height as measured in the garage (and as reported in telemetry) does not necessarily equate the actual ground clearance. For example, the splitter ride height sensor (on cars that have one) may be positioned a few centimeters above the bottom of the splitter. As a result, you’ll get a non-zero reading even if the splitter bottoms out. Free audio capture. And obviously every single car is different, so the first thing you need to find out when you start setting up a new car is what “bottoming out” means in terms of ride height reading.
Purposes of changing the ride height
1: Lower center of gravity means less lateral weight transfer, which means more grip
For cars that are not very aero dependant the ride heights are primarily used to affect the center of gravity. A lower sitting car generally has better handling because a lower center of gravity means less lateral weight transfer. And we’ve discussed in 5.3, lateral weight transfer reduces the total available grip.
1: Lower center of gravity means less lateral weight transfer, which means more grip
For cars that are not very aero dependant the ride heights are primarily used to affect the center of gravity. A lower sitting car generally has better handling because a lower center of gravity means less lateral weight transfer. And we’ve discussed in 5.3, lateral weight transfer reduces the total available grip.
2: Balance between downforce and drag
For cars where aero is a defining factor in car setup, the ride height is the key to optimizing aero performance. Each car is different, but in general there’s an ideal ride height range that produces maximum downforce. Similarly, there is an ideal ride height range that minimizes aero drag. These two ranges may or may not overlap. Each car is different and it takes a bunch of experimentation with each new car to find out what works and what doesn’t. By statically and/or dynamically adjusting the ride heights, you can optimize the aero performance of the car.
For cars where aero is a defining factor in car setup, the ride height is the key to optimizing aero performance. Each car is different, but in general there’s an ideal ride height range that produces maximum downforce. Similarly, there is an ideal ride height range that minimizes aero drag. These two ranges may or may not overlap. Each car is different and it takes a bunch of experimentation with each new car to find out what works and what doesn’t. By statically and/or dynamically adjusting the ride heights, you can optimize the aero performance of the car.
3: Ground clearance
The final factor, relevant for both downforce and no-downforce cars, is clearance from the ground. You may want to adjust the ride heights to avoid bottoming out on bumps and curbs. Like discussed in the spring rates article, bottoming out can cause handling issues as one or multiple tires may become unloaded or lose contact with the track altogether, and it can also severely lower speed when the car is dragging onto the track.
The final factor, relevant for both downforce and no-downforce cars, is clearance from the ground. You may want to adjust the ride heights to avoid bottoming out on bumps and curbs. Like discussed in the spring rates article, bottoming out can cause handling issues as one or multiple tires may become unloaded or lose contact with the track altogether, and it can also severely lower speed when the car is dragging onto the track.
Iracing Correct Camber Tool
Example
One of the most common setup scenarios is converting a qualifying setup to a race set. In most cases the additional weight due to the added fuel is bringing the car ‘out of tech’, which means it’s too close to the ground and isn’t legal to race. To pass tech inspection, you need to raise the ride height.
One of the most common setup scenarios is converting a qualifying setup to a race set. In most cases the additional weight due to the added fuel is bringing the car ‘out of tech’, which means it’s too close to the ground and isn’t legal to race. To pass tech inspection, you need to raise the ride height.
Typically, it’s best to keep a note of the target ride heights as they are in the qualifying setup and try to resemble those as close as possible on the race setup. In order to increase ground clearance, you’ll need to decrease the perch offset on each wheel, or increase the pushrod length (when available). Matching front and rear ride heights may be all you need to convert a qualifying setup to a race setup.
For cars where the gas tank is located far from the center of gravity of the car (e.g. the BMW Z4 GT3 has it’s tank fairly far back in the car), setting the race fuel ride heights could be trickier. As fuel is burnt throughout a stint the front or back of the car will get lighter, increasing the ride height. You may have to take this into consideration when determining the static ride heights with a full tank.
How suspension geometry affects ride height
Different simulators implement this differently, but in iRacing you cannot set the ride heights with one parameter. Instead, on each wheel you can adjust the spring perch offset, or increase the pushrod length (when available). Adjust these properties until your achieve the desired measurement for ride height.
Different simulators implement this differently, but in iRacing you cannot set the ride heights with one parameter. Instead, on each wheel you can adjust the spring perch offset, or increase the pushrod length (when available). Adjust these properties until your achieve the desired measurement for ride height.
Keep in mind that many suspension elements are connected. Significant changes to spring perch offset, or to pushrod length could also impact camber and toe. Each time you make a change to ride heights you should remember to also take a look at camber and toe. If your camber has changed, change it back to the old (desired) value. This may change your ride height again, so you may have to do a few iterations of ride height adjustment, camber adjustment, until you achieve the desired result. The same applies to each wheel’s toe-in.
When adjusting ride heights
You need to keep ride heights in mind each time you change any of the following:
Spring rates: Stiffer springs raise the car, softer springs bring it closer to the ground. When changing spring rates you want to make sure that you maintain the ride height from before the spring rate adjustment (otherwise you’ll be applying two changes to the car).
Tire pressure: The tire is effectively a spring, and significant changes in tire pressure affect ride heights too.
Camber & toe: As already discussed, camber and toe adjustments may affect the ride height. Modify the suspension geometry so that you achieve the new desired camber (or toe) at that same ride height.
Fuel load: Added fuel (per the example above, for full race distance as opposed to for qualifying) adds more weight to the car, which compresses the springs more, which reduces the ride heights. Each time you add and remove fuel you’d generally want to do so without actually modifying the static ride height (with some exceptions, depending on car or track).
You need to keep ride heights in mind each time you change any of the following:
Spring rates: Stiffer springs raise the car, softer springs bring it closer to the ground. When changing spring rates you want to make sure that you maintain the ride height from before the spring rate adjustment (otherwise you’ll be applying two changes to the car).
Tire pressure: The tire is effectively a spring, and significant changes in tire pressure affect ride heights too.
Camber & toe: As already discussed, camber and toe adjustments may affect the ride height. Modify the suspension geometry so that you achieve the new desired camber (or toe) at that same ride height.
Fuel load: Added fuel (per the example above, for full race distance as opposed to for qualifying) adds more weight to the car, which compresses the springs more, which reduces the ride heights. Each time you add and remove fuel you’d generally want to do so without actually modifying the static ride height (with some exceptions, depending on car or track).
Up to you
Once you understand what ride heights are and what interactions ride heights have with suspension geometry, you need to spend a lot of time testing and experimenting with different settings in order to find out what works with each specific car. And in a later article we’ll look more closely how to approach dynamic ride heights.