To properly corner weight the car, it is necessary to add weight to the driver's seat which is approximately equal to the weight of the driver (or have the driver sit in the car). 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. Yeah, I'm a little puzzled by my result when I let me car down on my new scales as well. 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. not to push it off the scales, to unbind the suspension (as the car is
The left side changes, of course, will be 4.75 times the multiplier for front or rear. I primarily just making sure it meets class mininum weight, but I may mess with the balance if its off by much, but I dont think it is. 2 coils cut off springs 4 corners. I gave up on running adjustable end links on
Free Download Chapter listings from. My car is a 1987 Honda CRX, set up according toITC class rules. If the car understeers or oversteers in only one direction, check the cross-weight percentage. the same time. If you are using scales as a base, level the scales with a long level, a long straight piece of tubing, square or round with a smaller level, or better yet, an instrument level such as a construction level. The spreadsheet's second page has a good article that goes into more detail of
You will have to repeat this every time you lower the car onto
can help us get our setup right with less testing. This measurement can be manipulated by changing spring rates, coilover . This approach is commonly used in oval track racing. 3. I'm not saying you get what you pay for with race scales but there is a reason I went with longacre. Same goes for for swaybar endlinks. Take care that the car does not accidently slide off the scale pads. I've had my cars corner balanced a lot, but never really looked into the science of it. This gets very tedious, given the number of iterations it typically takes to get the corner weights right. %, Bite =
I
Crossweight is calculated by adding the RF and LR weights and then dividing that sum by the total weight. tires.
Corner weights and chassis balancing - R/C Tech Forums To truly optimize your shocks, your overall suspension setup must be right, including ride height, camber, caster, toe, and the correct spring rates.
Need some dirt oval setup advice! | Hobbyist Forums important for oval racers, especially on dirt ovals. Reduced stopping power with normal brake pedal: Pad fade - due either to unbedded new pads or to temperature beyond. May 2017 -Dirt late model pinning RF & heavy axle tube. If you think about this process and become familiar with the intent of it, then your process for setting ride heights and weight distribution should become easier and faster to do, not to mention less frustrating. A 50% Cross Weight will yield a balanced handling car, one
On the other hand, it drives really, REALLY good for being setup by this idiot behind the keyboard, and I really don't wanna spoil a good setup by chasing after a perfect setup at least not yet. Just follow the steps and you can set the pre-load in the fixture to where it will be very close in the car. I was booked for 100 laps split across four or five sessions. Changing the ride height at any corner will change the cross-weight percentage. Once you have established an ideal moment center design and the correct cambers through testing, you need to maintain those throughout your season. When looking at corner weighting, the cross weight (diagonal weight) is the most important component. If you do have adjustable end links then disconnect
what he means is he's adding weight to the left rear and right front
The crossweight percent will have changed to, say 55.4 percent. All 4 scales must be within 1/8 of an inch. I added the
Once you get the car up on the scales you'll
you run on the track. They are never level. One of the problems with cross-weight is that it will change the handling balance from a left to a right turn. 10.
4 Things You Should Never Do In A Front-Wheel Drive Car Right Rear weight: < Enter your corner weights in pounds or kilos and click 'Calculate'. Wedge Delta can also be thought of
Any press releases or advertising will be deleted. Use a load of fuel for where you you want the car balanced, either at the start of the race, the end of the race or an average between the two. about 1/8" of wheel movement) to reduce the weight on the right front and left
left to right (measured with a digital caliper) and my ride height was pretty
Weight can be moved around at the track to fine tune the handling characteristics of the chassis. 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. The process is so basic to the setup of the car. "Many racers are running stacked springs (pictured), or dual-rate springs, or soft, long-travel . Tell the shop you will be disconnecting the rear sway bar when obtaining the estimate. Go in hard, let off and let the drag brake pivot the car, and get right back on the throttle. typically not concerned with bite and wedge delta because they usually
We run a fixed chassis meaning no suspension and the Briggs lo206 so we aren't sliding it around the corner but tracking almost like an asphalt Kart. Softer tire compound Right Rear Increase Right front and left rear Corner Weights Bicycling Left side tires lose contact with the racing surface More overall left side weight % So, deviating from those numbers will mean you have a design other than what was intended for the car. I've read all the info before, in various places, but it's good to have a refresher. I
It is important that you complete the corner weighting process before doing an alignment. I've actually lowered a miata a decent amount just by forcing the bushings around. adjustment so I have a history of each adjustment. Basically - after you finish the set up routine, the car goes in the hauler. racers add "wedge" by adjusting the right rear spring perch--they
Afterward you need to adjust the settings to the correct maneuvers. Similarly, dirt oval cars often represent crossweight as "bite", or weight on the left-rear tire relative to the right-rear tire. extra weight is on the left rear and right front tires which gives them
Crossweight is of no concern to the track officials. When you lower the panhard bar the rear roll center drops. Now that's pretty cool! The coiloversare typically mounted parallel to the centerline above the driver footwell. Oval racers favor left turns so they typically desire more weight
2 1/2 turns. difficult to position all 4 scales so you can just drive up on all of them at
All rights reserved. - Use blocks the same height as your scale pads to move the car off the scales to make adjustments.
Oval Set-up Black Book | IROAR - Radio Control Racing . You would be amazed at how much bushing twist can contribute on your suspension. To do this, we add five rounds of pre-load to the RF. This will pitch the vehicle's. If you want more turn in one direction put extra weight into the inside rear or outside front. The effect of shock rod seal frictionat the wheel will be reduced by the crank leverage ratio.
Kart Scaling & Weight Distribution - Woodbridge Kart Club difference that made. and measured between the outside bottom rim edge is 67.75" front and 69.875"
With the stock setup the car should have more grip
and stock rear sway bars connected. Delta is equal to (Right
Bite = Left Rear - Right Rear and a positive value means the
if you have any of the scales connected improperly (i.e. center of gravity (CG) height by using this page:
If your car's diagonal corner weights are not equal then its handling will be unbalanced--it will turn better in one direction than in the other (all other things being equal). Custom iRacing Setups and Paints for dirt oval and asphalt oval cars. 7. The other two corners will gain weight. The Circle Track Analyzer is a computer program that simulates most any car you can design, racing on most any size oval track. One of the most important aspects of racing is having a good handling balance. Struts and trailing arms generally arent great in this case as they have a lot of inherent bind. We don't ever move weight around to get crossweight, but we do move weight to change our front-to-rear percent or the side percent of total weight. %
typically not concerned with bite and wedge delta because they usually
But in a right turn, the opposite occurs and the handling is worse. You can estimate your car's center of gravity
turning the front wheels to measure caster. Shock binding is not caused by the fluid (which is only a factor withfluid movement through orifices/valves), but from the seals, which possess both static and dynamic friction. coil over 5 turns. , = change needed to get to target weight, Cross Weight =
not to push it off the scales, to unload the suspension (as the car is
upgrading our street stock suspension part 2 the rear end. decided to try 5 turns total of spring perch movement to balance the car. You can see in the "Target Corner Weights" section that the Left
You've mentioned "dead struts" a couple of times - what do you mean by that? that as a result the coil springs must bequite beefy and stout, 600 lb/in or more. balancing see my corner balance how-to and
Take the total weight of the car in the configuration you decide on, with driver or without, and to find the corners, do the following: TVW = Total Vehicle Weight = 2,800, LSP = left side weight percent = 0.54, FWP = front weight percent = 0.51, CWP = Crossweight percent = 0.52. It varies with weight removal, added. 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. on the right front and left rear tires. the RF coil over 5 turns. There are legal issues too at the front. Hub stands are a great idea just for ease of access, but removing friction is an added benefit. I see disconnecting the sway bar, and how to do it, but disconnect the shocks? can help us get our setup right with less testing. Step 1: Setup And Tuning The Tires Most regular RC cars use rubber tires. Multiply the wheel load of 685 times the motion ratio squared, 1.3611 times the shock angle cosine squared of 1.1056 and we get 1,030.8 pounds of spring preload. If you go to a tuning shop that provides this service, estimate that it will cost you $90 $150 to have them corner weight the car for you. scales are connected properly--you can really screw up your suspension settings
Corner_Balance.zip Excel spreadsheet. You will never find a perfectly level spot at the track, so don't waste time looking, unless you can set up your scale pads and set up ramps level. that turns equally well in both directions. Before putting your car on the scales you need to power up
Vehicle Scales | Corner Weight Race Car Scales - Speedway Motors suspension changes to track your progress. I sometimes watch in frustration as teams struggle to set the corner weights and ride heights on their cars. Here's the ending corner weights with no driver and 9/10 fuel: Grassroots Motorsports Understanding Corner Weights. The front will show close to 60%. It also helps when shaking the car to take the bind out of the linkages.
How To Corner Weight Your Car - Suspension Secrets And don't ever believe the track scales.
Circle-Track Setup: What Is Toe, And Why Should You Use It? you run on the track. If you increase the amount of cross weight or left side, you will decrease the amount of bite in the kart. 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. Maybe I'm over-thinking this, but I was amazed when I got my new scales, and let my car down on them for the first time.
In order to perform the set up routine the car needs to be completely ready to race. need to roll the car back and forth a few inches several times, being careful
No, not as in the law, but in being legal in tech. It's
rear. Cross Weight or Wedge. Proforms are cheap scales. Iretighten them after I've made all my adjustments. 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. but tend too love the 1/2 miles.I just cant figure out a way too get these. Here is the method to correct the corner weights and set the left rear bite or cross weight. If your car's diagonal corner weights are not equal then its handling will be
Then move components like the battery or fuel cell. I needed 3 linoleum tiles (0.045" thick
To favor right turns, put more weight on the
shocks set to same length left to right (front to rear will be different). Raising the rear end will also provide a little more on-power grip by keeping more weight directly above the rear tires during acceleration. Let's explore some ways to do this in an orderly and sensible way. The outer rear tire drives "around" the outer front tire, allowing the chassis to efficiently turn into the corner because the rear tire It is defined as the total weight resting on the right-front (RF) and the left-rear (LR) tires added together, and then divided by the total vehicle weight. is especially true if you don't have adjustable spring perches. But stagger is not a good idea on a road course or autocross either, where the ideal is 50-percent cross-weight and no stagger. Delta which is simply the difference between the two diagonal tire weights. And what do you mean by "lots of bearings"? How would you makesomething like that?
Dirt track racing - Wikipedia Right Front =
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. But this is almost never the case. To get good accuracy easily make sure you get the low hanging fruit first like removing the friction between the tires and the scales so there is no bind. rear. So we multiply the difference, or 4.2 percent, by 1.12 and we get 4.7 rounds of right side change to the spring pre-load, or 43/4 rounds. Check static weight before working on cross-weight. I
2. want balanced turning in both directions. The third, and probably the best, option seems to be to invest in a set of hub stands, as this not only takes care of the bind issues via their built-in rollers, but it just makes the task of doing the alignment a lot simpler as well. (Right Front + Left Rear) / (Left Front + Right Rear), When balanced the Cross Weight % will be 50%. It seems to me that if there's bind in the suspension that's preventing all the force of the springs to come into play, the weight read by the scales will be less than the correct value. LF coil over 5 turns. If you moved only one point, then the problems begin. Grassroots Motorsports Understanding Corner Weights
I would imagine that disconnecting the shocks is only applicable to setups where the shock and spring are separate, like a lot of solid axle cars, or Mk2 Supras in my experience.
Roll Center Explained - FMI Knowledge Base - FMI Racing How big is the track? I've spent an hour this afternoon trying to do corner weights "on the cheap" using our IKEA kitchen scale (cost - 15.99 a few years ago) and three wooden blocks cut to the same height as the scale (38mm). 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. spread when the car is lowered onto the scales. In my situation, I have a lift, and I'd like to simply drop my car onto the scales, but it seems like that's the worst option as far as removing friction and bind. scales. Find the difference from the desired average ride heights. Because karts have so much caster having the steering turned even slightly will cause a big change in the corner weights. (I suppose cooking oil, motor oil, KY, or Astro-Glide would also work). Front + Left Rear) - (Left Front + Right Rear) and tells us how much
LR 175, RR 350 - 350 175 = 2.00 multiplier for the rear.
How NASCAR Wedge Adjustments Work | HowStuffWorks Tuning with anti-dive probably won't be . Wheel Offset Changes. If you want to lower the rear of the car then retract the LR
On a road course, the cross-weight percentage should be very close to 50 percent, within a half-degree either way, to keep the handling balance similar in a right-hand turn compared to a left-hand turn. Lay the bag flat onto the scale pad, partially open to vent, lower the car into the bag. should have their spring perches in the same spot and your left rear and right
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. . [Up] [CornerBalanceCalculator] [CGHeightCalculator], This calculator takes your car's four wheel weights and calculates current
Bottom line, you can strive for perfection, but ultimately youll just make yourself crazy. The roll center is an imaginary point around which the rear of the race car rolls. Equal weight on each front wheel, same on the rear. surface. Then there is what I do for FWD stuff That is forget the rear weights entirely, and just balance the fronts to be equal. I don't like the lower weight ratings and plastic scale pads of proform. Get the numbers right and the percentages will follow. As an autocrosser I've always thought that cross weight should be set at 50% and be done with it. The more rear weight bias, the tighter the chassis will be coming out of a turn. 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. and Left Rear. measure (literally). First the tires. Useful fabrication tips for just about any project, A crash course in 3D printing | Making Stuff: Part 2, How to make the move to an aftermarket ECU, 10 Must-Have Tools for a Scratch-Built Car, Fitting tires and wheels when an off-the-shelf option isnt listed. On my ZX2SR my cross weight was consistently in the 49% range. Record these. Strive for repeatable and take the measurement as a data point, instead of an absolute. Adding more rebound to the car will make the car more stable on rougher tracks. W. William18 New member. how and why to corner balance a car. This keeps the ride heights as close to ideal as possible. Calculator, I used these scales to weigh the car:
The overall effect is much like having no shock in the equation. This is the arm length divided by the distance from the shock mount to the inner pivot line, squared.
RC Dirt Oval Basic Setup & Tuning Guide (21.5, dirt oval - YouTube Any corner weight adjustments that you make will impact the alignment of your car. springs settled over the first 3 months. Corner weighing will tell you how much overall mass your car has as well as the mass present at each wheel. 3) Reverse stagger: The opposite of stagger when your left side tires are .
Corner weights-cross weights - TenTenths Motorsport Forum I guess I should work on losing weight personally (i am 220~).
Corner weight system - R/C Tech Forums unbalanced--it will turn better in one direction than in the other (all other
Besides the eventual move to an adjustable ride height set up, I feel like I need 100 lbs or so more spring in the left front.