If you lower the ride height at a given corner, that corner will lose weight as will the diagonally opposite corner. Did you mean it was off several hundred pounds per corner? the sway bars because they fail so often and the bars only added a couple of For most karts, the following weight distribution is recommended: 43% Front Weight 57% Rear Weight 50% / 50% Left / Right Weight These are just recommended starting points. We used to run about 1/8 of toe-in at the local tracks, and this helps the kart to cut through a corner easier in the center, where the steering is the greatest. Right handers vs left handers feel quite a bit different-I run out of suspension on right handers much more often, and on left handers the car loves having me hanging out over the inside of the contact patches working the corner. Race Tires: Are You Ready to Spend Some Money? Just to confirm the theory I checked the corner weights with To do this you need to enter a corner at the car's limit of adhesion and then peel off the throttle aggressively. Static weight distribution is the weight resting on each tire contact patch with the car at rest, exactly the way it will be raced. The rear is 2.125" wider. Wheel offsets can make a huge difference in fine tuning the chassis which will allow the driver to find a good racing line on the track. important for cars with upgraded (stiffer) sway bars because they can exert a Even if you pay someone a small amount of money for their help, it will be far better than buying the scales yourself. Delta which is simply the difference between the two diagonal tire weights. When a NASCAR crewchief says he's "adding wedge", another. Do this at every wheel. If we subtract the existing ride heights from the desired, we have front low by 0.0625-inch and the rear high by 0.4375-inch. Right Rear = To truly optimize your shocks, your overall suspension setup must be right, including ride height, camber, caster, toe, and the correct spring rates. Afterward you need to adjust the settings to the correct maneuvers. On the one hand, I'd love to have my Supra corner weighted, just to see where it's at, see if there's room for improvement. left to right (measured with a digital caliper) and my ride height was pretty what he means is he's adding weight to the left rear and right front To increase rear weight, move weight as far back as possible. 4. Always try to start with the track bars first. Once you have established an ideal moment center design and the correct cambers through testing, you need to maintain those throughout your season. how and why to corner balance a car. These are your current calculated weights: Left Weight = suspension). Put the car on ride height blocks without the shocks in the car and then measure the shock length from center of bolt to center of bolt. Ok sounds good. As an autocrosser I've always thought that cross weight should be set at 50% and be done with it. You will have to repeat this every time you lower the car onto April 2017 -Bracketing settings, 4WD high speed pavement vehicle. So LF/LR = RF/RR is what you shoot for. By changing the weight distribution on the car, you affect the way your car will behave when cornering. If you raise the ride height at a given corner (put a turn in or add a round of wedge), the weight on that corner will increase, as will the weight on the diagonally opposite corner. So if you have 60% on the front , you should have 30% on each front wheel. Even 1/8 inch difference will make a difference, especially if you have Most oval track speedways are similar to those in the US for car racing such as sprint cars, speedcars (midgets) and sedans, with most tracks generally around mile (402 m) to mile (536 m) in length. In the example at the beginning of the article, this was the problem: a cross-weight percentage that was less than 50 percent, and probably off by at least two percent. Raising the rear end will also provide a little more on-power grip by keeping more weight directly above the rear tires during acceleration. Bite tells us how much we 1 of the section on "Adjusting The Corner Weights," and that is 685. And what do you mean by "lots of bearings"? Adjusting the corner weights is how we establish the crossweight percent, or what is often referred to as the amount of bite, left rear weight, or wedge. Some racers like to take matters into their own hands-and that's OK. front left and I run generally 34F/30R for the street and usually (again depending on the day) drop the fronts to around 30~ and the rears to 26 or 28. Corner weighting your car is I can see binding throwing off each corners weight but the sum should be the same. height and the shocks set to the exact same spring perch height Bite = Left Rear - Right Rear and a positive value means the I gave up on running adjustable end links on But this is almost never the case. You're better off not corner balancing the car than doing it on an unlevel Motion Ratio of the lower control arm. You can drop the front end slightly or raise the rear end for more aggressive turn-in. If you had a car with a fully rod-ended out suspension that frictionless and frictionless tires you wouldn't need to roll the car around or bounce it or anything. The problem with this option is simply that hub stands aren't cheap - the lowest priced ones I've found are $849, kind of a lot of money for something most people wouldn'tdo all that often. Ideal weight percentages: Front - 43-45% Left - 53-56% Cross - 52-54% What do these numbers mean? I stretched my tires to get the RR right and now I'm . Forum Actions: Forum Statistics: Threads: 167; Posts: 1,367; Last Post: . Adjustable end links are more Oval rear should be the same. LR = left rear. I race in a spec class, so everyone is using the same equipment. 45. This is for a race prepped 1984 Audi 4000 quattro(2375lbs. Wedge To favor right turns, put more weight on the This allows a slightly lower rear stance, which provides a good weight transfer entering a corner. Unsure about autox. Finding The BBSS Front Spring Pre-Loading If we are running twice as stiff a RR spring as the LR, we would need to change the height of the LR spring twice as much as the RR spring so that we don't affect the ride height as we hunt for the correct or desired weight distribution. typically not concerned with bite and wedge delta because they usually Here is the method to correct the corner weights and set the left rear bite or cross weight. 5. for the front and rear sway bars and installed them with my girl friend sitting of the scale to take a reading. Exhaust/Headers, Limited Slip Differentials and Fuel Injectors, Engine Dyno Tuning, Racing Wheels and Air Dam/Splitters, The Costs of Racing Personal Safety Equipment & the Racecar, Brake Pads, Fluid Routine Maintenance Timeline, Dealing with Cosmetic Bodywork: Painting the Racecar Interior. 11. Choose the cold temperatures because when the tires get hot, they will expand and your ride heights will be providing more adequate heights to pass tech after the race. Thanks for posting this. And since the necessary scales to complete this process cost in excess of $1,000, I suggest you have the corner weighting done by finding another club racer in your area who has (or knows someone with) access to scales and would be willing to help you. If the car feels loose on corner entry, lower the left track bar. Today, dirt late model racers are using cutting-edge tools to pinpoint where gains can be made based on hard data. Do not copy these ride heights; they are only used as an example. The advantage to wedge is that the left rear tire carries more load, so the car drives off the turns better. Sprint kart classes are broken down into driver's age, engine package, and total vehicle/driver weight. Less fuel equals faster speeds. That math gives us a percentage number to . will help with those turns. Those will tend to reduce friction and bind at the expense of NVH and added wear. . Bite tells us how much we are favoring the left rear tire for better acceleration out of left If you're setting up a FWD race car, and you can see this in historical VW Golf or original Minis, they often lift and inside rear-wheel. Well there is a bit more to it than that. Crossweight is calculated by adding the RF and LR weights and then dividing that sum by the total weight. I highly recommend using a laser level to confirm the 4 scales are level to one you run on the track. Or it could also be possible that the signal is smoothed in the programming. rear. You should read the spring preload amount. Plus it sounds like street and autocross pressures are about the same stagger front to rear, so it really shouldn't have a noteworthy impact. [Up] [CornerBalanceCalculator] [CGHeightCalculator], This calculator takes your car's four wheel weights and calculates current Cross Weight % = When a NASCAR crewchief says he's "adding wedge", When I weigh my cars I try not too overthink all this binding stuff. My big stumbling block on this subject is how to get accurate readings by removing all the friction/bind from the tires, sway bars, bushings, etc. March 2017 - F1 suspension rules, independent rear suspension for dirt oval. The intent of the track scales is to determine a car's total weight to meet minimum weight rules and left side percent (or right side weight) to meet a side weight rule. If not, adjust the ring until you read that number and then you can install the spring in the car and be very close to the correct ride height. [Up] [HarnessInstall] [WingInstall] [RemoveA/C] [OilCooler] [FireSuppress] [CutoffSwitch] [RaceExhaust] [Differential] [CornerBalance] [CatchCan] [RollCenters] [FrontBumpSteer] [Alignment] [ShockTuning] [Aerodynamics] [CatRemove]. Now that we have the front-to-rear rake set, we adjust the side-to-side rake. turns. After these items are completed, it is necessary to corner weight the car. This is my 2001 S2000 with 1/2 tank gas, 216 (adsbygoogle = window.adsbygoogle || []).push({}); If you prefer Microsoft Excel a Corner Weight spreadsheet is available for download here Intercomp 102030 5X5 Hub-Mounted Corner Weight Scale. They're made by Proform, and are quite a bit less expensive than the ones made by Intercomp, but they got good reviews. Front and Right Rear need 51 lbs of additional weight to balance the car. Of course you can add too If it slows to 100rpm, the outside wheel will spin at 300rpm. - can make your car dive like a dump truck or a block of wood on ice. Carry some in your tool kit and buy tarus wheel studs if you want a dirt cheap slightly longer wheel stud to have more safety. The car literally registered several hundred pounds less that what the weight finally settled at after I jumped up and down on the door sills for several minutes. February 2017 -Suspension design process. One of the most important aspects of racing is having a good handling balance. I recommend you start with your car at your desired ride Measure control arm angles after each change. the scales. Splash = 2-3 gallons, 1/2 can = 5-6 gallons, 1 can = 11-12 gallons, 1 1/2 cans = 17-18 gallons, 2 cans = full tank. 1. Ask your chassis builder or establish what you want and decide that these will be what you run from now on. This can make maneuvering in traffic difficult, even dangerous. And actually you'rereally not going to changefront/rear weight balance with ride height changes, so itreally only matters that pressures are even side to side. pounds of preload to the scale weights. It is best to make small changes at each corner, instead of a big change at one corner. Would be interesting to see how close to ideal I got it though, given how well it handles already. typically not concerned with bite and wedge delta because they usually "Springs and chassis components can be adjusted to push down on one rear wheel," Bickel said. Bite = Left Rear - Right Rear and a positive value means the However, you can choose to use them. I'm off by 0.1% (see numbers on left side of the spreadsheet). Cross weights can be changed by making ride height adjustments to the coil-over suspension by either winding the lower spring platform up or down. It puts power down better, and any decent FWD car will be carrying a wheel in the air around a turn anyway, so by default the outside rear gets 100% weight transfer when it's being asked to turn anyway. At the right rear, a quarter-inch change in the height of the end of the link will change the angle and can make an asphalt car undriveable. The car should be at minimum weight, using ballast as needed to make the proper weight. I was booked for 100 laps split across four or five sessions. Don't just blindly cross weight it thinking it's the "right" way. unbalanced--it will turn better in one direction than in the other (all other A perfectly corner balanced car will handle the same when turning left and right, and will maximize the tire contact area on all four corners. Can do to just left sidesor right sides, or to all 4. One of the keys to obtaining a good setup is using the correct procedure to weigh your race car. (adsbygoogle = window.adsbygoogle || []).push({}); I still needed more weight on the Left Front and Right Rear so I added + 4