The higher the caster stagger, the less steering effort required. This will tend to give you a loose feeling upon corner entry. Differential Ratio The differential is a gear assembly in the rear end whose purpose is to distribute torque to the rear wheels for traction. It is always a good idea to clean your laptop screen or monitor before gaming. Learn how to clean a laptop screen or monitor safely with a few different alternative methods.
The ratio expresses the number of turns required by the pinion which is attached to the output shaft of the transmission to turn the drive axle one revolution, i. A higher number 6. Short gearing gives quicker acceleration, but because the engine must turn faster, fuel mileage and top speed are lower. Tall gears give smoother acceleration and higher top speed, at the expense of quick acceleration.
We are allowed to choose from no less than 49 different ratios with an adjustment range from as low as 2. When you change the differential ratio, you change all the final drive ratios together proportionally. On short tracks you will want to choose a higher differential ratio because quicker acceleration will be a must at tracks where speeds are not as high.
At super speedways you'll want a smaller ratio for top speed since quick acceleration is not necessary on a track where you're at full throttle most of the time. The most important factor when considering what ratio to use is that you don't choose a ratio that is too high. Too high a differential ratio will result in running higher rpms. If, by the time you reach the end of a straightaway, you're running higher than rpms.
The rev limiter is used to prevent us from running too high an rpm, which could result in a blown engine. You must watch your tach when changing gear ratios. If you're running too high an rpm you will also notice it through the sound of your engine as a "missing" sound. As you adjust other chassis components, you will most likely find yourself having to change your differential ratio. As you find more speed through the corners, you'll eventually find yourself on the throttle quicker.
Since you're on the throttle sooner you will be running a higher rpm towards the end of a straightaway. This is likely going to force you to make a differential change. Provides quicker acceleration, but slower top speeds. Provides slower acceleration, but higher top speeds.
This is a non-adjustable option that is basically used for comparison purposes. The final drive ratio represents the number of engine revolutions to rear wheel revolutions. The final drive ratios can be viewed for all four gears. A higher number means a lower or shorter gear.
Your final drive ratio will be the same as your differential ratio. Front Bias The Front bias can be adjusted by clicking the weight bias tab on the garage screen.
Front bias is the amount of weight on the front of the chassis as compared to the rear of the chassis. Front bias is determined by placing lead weight at various points as low as possible in the chassis. Sliding this weight forward gives you more front weight or bias. The most front bias were allowed is The least amount is Generally speaking, the flatter the track, the more front bias required.
The higher the banking the less front bias required. This is because the higher banked tracks require less braking which in turn means less weight is being transferred to the front of the vehicle.
Less front bias or more rear bias would be preferred at a track like Talladega. A slower track that requires shorter gear ratios, will also require less front bias. This is due to the problem of wheel spin that can occur during acceleration.
You would rather have less front bias or more rear bias to help transfer weight to the rear quicker to avoid wheel spin. Just the opposite would be true when a higher gear ratio is required. The less front bias you run the looser the chassis will be. Experimentation once again with all these variables will be the only way to correctly determine the proper front weight bias given the various circumstances.
Another factor that must be considered when dealing with front bias is Fuel. As fuel is burned, your rear weight distribution is lowered. Although your not directly changing your front bias, you will be affecting the amount of weight that is being transferred as fuel is burned. This will result in an ever changing car as fuel dissipates.
Front Bias synopsis: More front bias will tighten the chassis. Less front bias will loosen the chassis. Front Brake Bias Many people believe that the brakes in a racecar are used for nothing more than slowing or stopping the car. Nothing could be further from the truth. Properly adjusted brakes can improve lap times by allowing you to get into a corner better. Front brake bias allows us that same exact adjustment.
Because of these varying factors more or less front brake needs to be "dialed" into the car. Since this will vary with each corner at each track, it is important to find the right balance as not to upset the chassis when you apply the brakes while cornering. It is important not to confuse a loose or tight condition upon entry with a front brake bias problem IF your problem doesn't occur when using the brakes.
On the other hand, your chassis may not be tight or loose on entry, but because you have the incorrect front brake bias set into the chassis, you're creating a problem when using the brakes. It is real easy to mask or create an I'll handling car getting into a corner by making a front brake bias adjustment. The more front brake bias higher the number you have set in the car the tighter the car will be on entry.
The lower the number the looser the chassis will be. This tight or loose condition from front brake bias will only occur while your on the brakes entering the turn. Some may try to add front brake bias to tighten up the chassis going in, but unless your using the brakes going in, changing front brake bias will be useless. Plus the fact remains that you are only masking the problem of the loose condition by trying to compensate with a brake adjustment.
You might want to adjust the chassis elsewhere to tighten the car up on entry. So how do you know when you have the correct amount of front brake bias? I believe the correct brake bias is determined by how the chassis reacts when hitting the brakes hard going into a corner without locking them up. It is important not to steer any more than is necessary. Any added steering inputs can throw off your results due to the added weight transfer that occurs while turning.
How did the chassis react? You ll probably also want to make sure that you re not using any caster stagger during this test. Once you have the brake bias the way you want it, you can go back and work on the compromise between caster stagger needed for turn-in but not so much it causes you to use to much front brake bias. Front Brake Bias synopsis: More front brake bias will tighten the chassis entering a corner under braking. Less front brake bias will loosen the chassis entering a corner under braking.
Front Roll Couple Whenever you turn, there is going to be some body roll. Body roll has to be handled by the suspension system so the tires won t break traction. Since Cup cars use independent suspension, the front and rear of the chassis handle their share of body roll separately as it passes through the front and rear roll centers. Roll couple percentage is how much body roll is distributed between the front and the rear suspension systems.
Since we know the stiffest end of the car will slide first, roll couple provides a pretty good indication of whether the chassis is going to be loose or tight. If the front slides first, the chassis is tight and if the rear slides first the chassis is loose. Figuring out roll couple is a complex formula that includes roll rate, track width, spring rate, sway bar lengths and thickness, anti roll lever lengths and rates, and tire pressures.
Increasing the front springs and sway bars as well as decreasing the rear springs and sway bars will increase roll couple while doing exactly the opposite will decrease roll couple. The higher the front percentage number, the more under steer pushing there is in a chassis. Conversely, the less front roll couple, the more over steer loose. The reason the front roll couple percentage is so much higher than the rear roll couple is because most of the weight transfer from inside to outside during cornering should be led by the front or non driving wheels.
There is also a direct correlation of weight distribution and roll couple. Typically, as you move weight forward in the car, the less amount of front roll couple is needed.
As you move weight back more front roll couple would be needed. Adjusting roll couple should be done before adjusting wedge in regards to tightening or loosing the chassis. It is possible that taking out wedge could have a negative impact on right front tire wear as more dynamic weight may be distributed to the right front from the heavier load that was jacked static negative wedge to the left front and right rear.
Adjust roll couple before adjusting wedge to tighten or loosen the chassis. Front Sway Bar A sway bar is also known as an anti-roll bar or stabilizer bar. The purpose of a sway bar is to control body roll through a corner.
This is done with a bar that connects to both front lower a frames. Without getting to technical, a sway bar acts as a third spring to help balance out weight transfer during cornering. The sway bar is measured by the thickness or diameter of the bar. The thicker the bar the stiffer the bar. Here are the diameter choices of the bar: 0.
Generally speaking, the larger the bar the less the body roll up front. The less the body roll the tighter the car becomes. Fine tuning with sway bars is an easy way to compensate for roll couple or body roll.
Front Sway Bar synopsis: The larger the bar the tighter the chassis. The smaller the bar the looser the chassis. Front Toe Out Front toe out is when the tires are farther apart in the front of the tire than the back. Toe in would be just the opposite. Front toe out is utilized to help prevent tire scrub while cornering. Within the sim we are allowed adjustments that range from Under no circumstances would you want a toe in condition. The majority of setups usually require a setting of less than 0.
I wouldn't run anything less than. Larger radius tracks with long corners would require less toe out. More toe out will help the front end stick entering a corner. A car will run faster with the toe straight. By monitoring tire temperatures you can tell if you have a toe problem with the chassis.
Excessive toe out would show higher temperatures on the insides of both front tires. Excessive toe in would show higher temperatures in the outsides of both front tires. Front toe out isn't an adjustment that has to be changed or monitored as often as camber. Start with an adjustment of 0. Adjust the toe slightly only when the rest of the chassis is real close to being correct. Fuel Level Your WC race car comes equipped with a 22 gallon fuel cell.
Your allowed to adjust the fuels levels from 1 gallon to 22 gallons for practice sessions only. All races as well as qualifying must begin with a full 22 gallons in the tank. Gone are the days of deciding how much fuel you want to add during a pit stop. We are now faced with 5 options. A splash of fuel will give you gallons. These options can be selected by hitting the left or right arrows on your keyboard after hitting F3. The less fuel your carrying the faster your car should be.
This of course depends on tire condition. The important thing to understand about fuel, is how it effects the handling of your car as it is burned. Multiply that times 22 gallons and you have an extra This is important to remember when taking on less fuel late in a race.
If your setting your chassis based on using a full 22 gallons, you may think that by taking less fuel that you will be quicker. Depending on your setup that might not be the case. The best solution is to practice your setup with different fuel levels to see how it performs.
It's also possible to make a wedge or track bar adjustment in the pits to compensate for how your will react with less fuel. Fuel Level synopsis: Less fuel equals faster speeds. The less fuel in the tank the tighter the chassis will become. Grill tape is nothing more than duct tape. The only component were worried about is the radiator. The more tape you apply the hotter your engine will run. Running excessive amounts of tape for a long period of time will result in engine failure.
So why put any tape at all on the the front end? Instead of air going through the car, air is being forced around the car. This places more down force on the front end. More down force will make the front of the car turn into the corner quicker.
Excessive amounts of tape can cause too much down force making the rear of the car lite creating a loose condition. Weather is another factor you must consider when deciding how much grill tape to use. It stands to reason the hotter the day, the higher your water temperature will be.
Therefore with the warmer weather you'll find yourself having to run less grill tape to allow more air flow through the front of the car. In other words, running the same amount of grill tape on the same track in 50 degree weather may cause an overheating or engine failure problem with the weather being 85 degrees. Be sure to keep an eye on your gauges, or you may find yourself pitting to remove some of that tape. Try to get away with as much tape as possible on superspeedways without causing excessive water temperature.
More tape will decrease lap times. If you discover you can get away with running more tape, but become to loose, adjust for the looseness elsewhere.
The hotter the weather the less tape you can use. Tape causes aerodynamic changes that have very little affect at speeds less than MPH. Left Bias The left bias can be adjusted by clicking the weight bias tab on the garage screen. Left bias simply means how much weight is on the left side of the car compared to the right side.
Between all the weight adjustments allowed, this one is the easiest to figure out. If you could run your car, with the weight being equal at all 4 corners entering a turn, then you would run faster than anyone else in the corners.
With perfect weight distribution you would have perfect tire temperatures. Perfect tire temperatures equals the maximum traction you could attain. This is what were all trying to accomplish with every single adjustment we make on a racecar. As heavy as WC cars are, left side bias on an oval is simple to deal with.
Always keep as much weight as possible towards the left side of the chassis. Whenever your dealing ONLY with left hand turns, always keep the left side weight at More left side weight allows you to take left hand turns at a higher speed. These obviously would be the road courses. Although at a track where there are more right hand turns than left, you may favor a higher right side percentage. This will allow you to get through those right handers a little more quickly, but at the sacrifice of losing speed going through the left handers.
This still could be advantageous if there are few more turns going right than left. Higher right side bias will cause the car to Under steer when making a left hand turn.
Rear Sway Bar The purpose of the rear sway bar is the same as the front sway bar except it controls body roll at the rear of the car. The rear sway bar connects in the back between both rear lower trailing arms.
As with the front sway bar, the rear is adjusted by changing the diameter of the bar. The rear sway bar range of adjustments are as low as 0.
This differs by a half inch over the front sway bar, yet the rear offers no less than 26 adjustments in 25 hundredth increments. The larger the bar the stiffer the rear becomes.
But by making the rear stiffer, it has just the opposite effect that occurs at the front. A larger rear sway bar will actually loosen the car up due to the fact that the way the weight is being transferred at the rear, is just the opposite of the the way the weight gets transferred at the front of the vehicle.
Rear Sway Bar synopsis: The larger the bar the looser the chassis. The smaller the bar the tighter the chassis. Ride Height The chassis ride height is simply the distance measured in inches from the bottom of the frame rails to the ground.
This measurement is taken at all 4 corners of the car where the frame rails are lowest to the ground. Ride height is adjusted by turning down or up on load bolts located at each corner of the car on top of each spring. Ideally you would want to run your chassis as low as possible.
The lower your ride height, the lower your center of gravity. The lower the center of gravity, the lower the overall weight is to the ground. The lower the weight the less weight transfer will occur while cornering. There are a number of criteria that must be considered when adjusting ride height.
These adjustments are built into the chassis itself. Rear roll center can be taken care of by adjusting the track bar. Check you tire temperature for proper camber angles. The most important factor we must consider is chassis clearance. If the ride height is set to low the car may bottom out on the track.
This will more likely occur at high speed high banked tracks where the centrifugal forces are higher higher or at road courses where there are dips in the track. If the car bottoms out in the rear you will most likely get loose. Bottoming out up front will result in a push. If you bottom out you can do one of two things.
You can raise the ride height or run stiffer springs. Personally I've always believed that lower was better, but I also believe that softer springs are better. Again, this theory depends on a lot of other adjustments set within the chassis, so experimentation is the only real answer. Lowering the ride height at those same corners will also lower the RF. The corner that is opposite is the LR. At the LF we are allowed to set the ride height as low as 4.
The higher the front of the car the tighter the car will be. The LR can also be set as low as 4. Adjusting the ride height effects the way weight is being transferred when cornering. Running a higher LR ride height also puts more weight on the RR. This will cause a loose condition entering the corner. Another thing you must consider when raising the ride height in the rear is how it affects the aerodynamics of the car. With that big spoiler running across the back, it will create more drag because it will be catching more wind.
This will slow your straightaway speed. With more wind catching the spoiler it will also create more down force on the back of the car which should allow the back of the car to stick better in the corners. Running a higher ride height may allow a lower spoiler setting. Springs will play an important rule in determining your overall ride height. In general, the lower the car, the faster the car should be, but possibly at the expense of bottoming out.
On larger tracks where moderate acceleration occurs at the mid portion of the corner, having the CG too far forward will result in a larger wheel steering angle in the corner and typically a push under steer exiting the corner.
On short tracks where you have heavy acceleration, having a CG too far forward can result in rear wheel spin and a car that feels loose overseer when trying to exit the corners. The higher the CG is above the ground the more weight will transfer to the outside tires in a corner. A higher CG can also exaggerate the affects of Tip E below.
Raising or lowering the CG can impact suspension geometry such as rear axle steer or camber gain in the front suspension. Let the front roll center fall where it may in order for the front suspension to have good camber curves. Use the rear roll center to tune your race car's handling. Elevating the rear roll center tends to make the car looser overseer in the mid portion of the corner when the centrifugal force is highest.
Many people refer to this parameter as roll couple distribution. There are no fixed numbers for this parameter. Your settings back at tip A will affect your ideal numbers. Anybody can crank on the weight jacks until the race car has balanced handling. Cross weight preload is a way of measuring how efficiently the car is balanced.
After you make the spring change it will be necessary to readjust your corner weights. Typically for pavement tracks the front has a larger number. Dirt tracks typically require a larger number at the rear. In all cases, changes that decrease the rear number make the car tighter and increasing the rear number makes the car looser in the turns.
While weight jacking is a quick and simple way to change the handling of the race car, it is still a crutch. Follow instructions in the manual on how to interpret the preload and determine what the race car wants for springs.
Before your race car goes on the track or at the shop the tires are "Cold. As soon as you stop the tires are still "Hot. This measurement can change from cold to hot conditions just like the pressure. A computer is just dumb box. It only know what you tell it. For example, if you were to race your car and have the right front brake rotor glowing bright red you would see this and would be registered in your brain.
The computer can not see t he car and does not know that a large heat source is near the wheel and tire. The temperature of a wheel can be elevated to the point where more heat is reaching the air inside the tire from the hot rim than is coming from the tread surface of the tire. If the software were to read only the tire temperatures it may suspect a slightly high air pressure, but with the rim temperature the software would know about the heat coming from the brake rotor.
A good place to take the rim temperature is where the center flange of the wheel meets the rim portion of the wheel. Ride Height synopsis: Too low a ride height could cause the car to bottom out. The higher the RF ride height the tighter the car will be. This guide was awesome! Thanks a lot for making it. I was also wondering, are there any tricks you have to make your tires wear slower without damaging speed.
When you enter the corner you are going to slow down. In order to slow you must lose kinetic energy. I have little experience on dirt but can definetely notice this! Your email address will not be published.
Comments This guide was awesome! The artistry comes in when you actually do it. Hi Jeff! Your email address will not be published.
It is now, thanks for asking. Leave a Reply Cancel reply Your email address will not be published. Menu Close Menu. OSR Menu.
No ad blocking software is permitted on this website. Please disable any ad blocker you have running then refresh the page. Experience dictates if this is a good gamble. Easy to drive. Usually frees up as the tires wear. Not a good set up for the inexperienced driver. Be aware that some times cars don't seem to follow the rules. You can get conditions that contradict the rules. Generally, you see this condition when you have gone to extremes with adjustments.
If you get outside the range with your adjustments many things can happen to confuse the issue. When your car does not seem to get around the turns right you should first have a look at any adjustments that are to an extreme compared to what your car builder recommends or from what you have learned from your own experiences.
The soft push occurs when you get below the spring rate that holds the front end up. The suspension runs through its full travel too quickly and in effect bottoms out as the car enters the turn.
What if you are already too soft? For example, lets say you typically would run 's in the front of a coil over car or 's in the front of a big spring car. The car has been pushing so you keep dropping front spring rate. Now, as an exaggeration, you are down to 's in the front of the coil over car and 's in the front of the big spring car. The car will roll through the suspension travel too quickly and the car will push even worse.
The point is that you can be fooled into going softer on the front spring rate to cure a push when the reality is that the front springs are fine but another adjustment would be a better option. When you get too soft in the front the car can push and installing a stiffer front spring actually makes the car turn better. Just as with the soft push the same condition can occur with the rear springs.
If you get the rear too soft the car can get loose as the suspension travel is used up too quickly and effectively bottoms out. In this case, a stiffer rear spring can hook the car up better. Sometimes your car will skate in the turns. The whole car seems to slide up into the second groove. The driver has trouble running the low line.
Many times the driver explains this condition as a push. Panhard Bar Too High - A panhard bar that is too high can cause the skating condition. As the car gets to the "cut zone" the high panhard bar can pull the rear of the car up the track into the second groove. When this condition occurs the driver often steers to the right to catch the car as it enters the turn. By the time the car gets to the middle it is out of position and the angle of the car is pointing towards the wall instead of down the straightaway.
At this point, the driver feels the car push and reports that information to the crew chief. Be aware. In this contradiction, lowering the panhard bar can make the car turn better. Too Much Rear Weight - Too much rear weight can make the car skate very similar to when the "too high" panhard skate occurs.
The pendulum effect of the rear weight pulls the rear of the car up and the driver corrects to the right. A push then occurs at the middle which the driver feels more than the entry problem. The driver then reports a push to the crew chief. In this case, less rear weight would reduce the skating problem.
Awareness of "the soft push" and "soft loose" will allow you to think of other adjustments when "the rules" are not working out. Break the corner down, section-by-section, and you will speed both your car and your learning curve. Crew Chief Communication Responsibilities Make it easy for the driver to provide clear and informative feedback.
Driver Communication Responsibilities Feel the car and communicate the characteristics of the car in order. Breaking Down the Corner To achieve clear and concise information it will help the driver and crew chief if they look at the corner in sections. Corner Entry The corner entry is the area where the driver lifts and begins braking. The Cut Zone The cut zone is the area just past the corner entry where the car begins to turn or cut down into the corner.
The Middle The middle is the area just past the cut zone that contains the actual apex of the turn. Acceleration Zone The acceleration zone is the area just past the middle of the turn where the driver gets down harder on the accelerator. The Exit The exit of the turn is the area just past the acceleration zone where the car makes the final approach to the straightaway.
Making the Most of the Corner Breakdown Feedback In order to communicate properly each section of the corner should be discussed in order.
0コメント