I usually mark an even inch and write that inch number on the tape. 12. 6. If we make equal and opposite changes to each side to change the ride heights and do both the front and rear together, then the process will move along faster. Do not adjust any other wheel's spacing. Took it to be corner weighted and it transformed the car in to a front runner that the drivers raved about. This approach is commonly used in oval track racing. Your results might be different from mine. Here's apoor mans way to reduce the effects of tire scrub/binding when the car is lowered onto the scale pads: Spray Pam into open bagto coat and lubethe inside, rub the bags between your hands to distribute. Also double check that the
Open timing on motor and esc. Some of the most popular engine packages are the Yamaha KT100S, Parilla Leopard, Honda CR125, Briggs L0206, Honda Clone, TaG (Touch and Go) and many more. rear should be the same. 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. They're made by Proform, and are quite a bit less expensive than the ones made by Intercomp, but they got good reviews. It also helps when shaking the car to take the bind out of the linkages. On Dirt cars, adding Rebound to the Right Rear will make the car more stable when it slides into the cushion. However, for dirt oval RC cars, foam tires are the norm. Or use an automotive tuning shop. Same goes for for swaybar endlinks. First the tires. Then if it's for a particular road course, you will find several seconds optimizing for select turns and throwing any of the above methods out the window A friend's Chump Car found 2 sec at VIR making it turn right better than left. then set corner weights and cross weight. 3.
Weight Training: Everything You Need to Know About Race Car Weight shocks set to same length left to right (front to rear will be different). Keeping track of Bite and
However, if you have to apply opposite lock steering (turning the steering wheel to the right) and you drive the car throughout the corner balancing it with the throttle . To carry the wheel load, the spring must be compressed quite a bit. 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. I race in a spec class, so everyone is using the same equipment. That is equal to 7/8 turn of the adjuster. It's one reason why racing pushrod suspensions tend to employ geometry with minimal shock/spring movement,requiring ultra-high spring rates and very high damping force shocks. Always
want balanced turning in both directions. see on the right side of the spreadsheet's "Target Corner Weights" section that
So 2.5" springs and experimenting is the way to go- I think I know that much.. . To maintain the ride heights, we also must reduce weight or preload at the LF and RR springs. ride heights after every change. On oval track cars, cross-weight is usually used in conjunction with stagger (where the right rear tire is larger in circumference than the left rear tire) to balance handling. Its important to measure and note your
If you want to raise the rear of the car then extend the RR
The crossweight percent will have changed to, say 55.4 percent. racers add "wedge" by adjusting the right rear spring perch--they
Right Front tires. Step 1: Setup And Tuning The Tires Most regular RC cars use rubber tires. B. Ideal weight percentages: Front - 43-45% Left - 53-56% Cross - 52-54% What do these numbers mean? When a NASCAR crewchief says he's "adding wedge",
Here are some points to remember when weighing your race car: How to renovate an old mill | Making stuff: Part 6, Tech tips | Understanding fender rolling, downsizing tires, wheel spacers and what makes a race wheel, How to build a splitter for only $100 | Against the wind: Part 3. [Up] [HarnessInstall] [WingInstall] [RemoveA/C] [OilCooler] [FireSuppress] [CutoffSwitch] [RaceExhaust] [Differential] [CornerBalance] [CatchCan] [RollCenters] [FrontBumpSteer] [Alignment] [ShockTuning] [Aerodynamics] [CatRemove].
PDF UNDERSTANDING CHASSIS ADJUSTMENTS - Longacre Racing Bite tells us how much we
If you shocks are working normally they are not worth worrying about.
How NASCAR Wedge Adjustments Work | HowStuffWorks Calculate the rear weight bias by adding the rear weight (LR and RR) of the chassis and dividing it by the total weight of the chassis (LF + RF + LR + RR). Cross weight and left side work backwards in terms of adjustment. turns. 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. "This is called chassis pre-load. We had a good Miataset up for ST. Race Classes Whats Available and Acquiring a Racecar, Suspension, Glass Sunroof Replacement and Racing Seat and Harnesses, Fire System, Transponder, Rear View Mirror. Right now I have (IIRC) 350 lb front and 200 lb rear springs (koni sport, eibach pro line, ST anti sway bars) . You will have to repeat this every time you lower the car onto
This adds pressure to that end of the car just like putting the paper wedge underneath the table leg. Wedge is a term used in the
The tiles I
Static weight distribution is the weight resting on each tire contact patch with the car at rest, exactly the way it will be raced. Or do you just mean an old, worn-out strut? That's all total speculation though. Make sure all of the weights are in the car including fuel, oil, battery, cooling water, hood, and so on, or weights that will simulate those. Calculate the average front and rear desired ride heights. I use 2x6 wood planks as ramps to drive the car onto
much Wedge Delta and make the handling worse. 50% then Wedge Delta will be 0. bite, a negative value means the Right Rear is favored. things being equal). %Right Weight =
right swapped). The more power a car has, the more that static weight over the drive wheels helps acceleration off the corners.
How to Properly Use a Penske Shock Tuning Guide to Optimize Your What Spring Rates To Use In Your Race Car - MotorTrend Jun 7, 2018 #8 . Remember that changes in stagger, tire pressures and springs will change the ride height and alter the cross-weight percentage. of the scale to take a reading. Muscle Car. I needed 3 linoleum tiles (0.045" thick
Additionally, it is much more difficult to change rear percentage much, since rear weight is mostly a design function. intentionally favor a turn direction. First some baselines. The first spreadsheet below is what I started with. Corner Weighting
Dirt Race Car Handling Problems; Diagnosing and Fixing - Hogan Technologies Sprint kart classes are broken down into driver's age, engine package, and total vehicle/driver weight. front left and
T-Bucket . If you align your car prior to doing the corner weights, it will be necessary to verify the alignment again after the corner weighting is completed. Here is what you do. You can make this adjustment in several ways: If you don't want to change the ride height of the car then
Road racers can take a page out of the oval racing book and
This is my 2001 S2000 with 1/2 tank gas, 216
Less fuel equals faster speeds. spring perch so I left my jacks in place between lifts and only put two lug nuts
All rights reserved. If you lower the ride height at a given corner, that corner will lose weight as will the diagonally opposite corner. "If your car is really tight or really loose during hot laps, you have to take a look at the things that are going to make the biggest difference. You can
Take your shock, compute the spring preload, and compress the shock/spring combo to the installed spring height in your spring rate fixture. Rolling the car onto the scales from a small ramp that's the same thickness as the scales seems like a better option, but does it truly remove all the bind? Still, it is a worthwhile goal to strive for 50 percent left-side weight. Here's the ending corner weights with no driver and 9/10 fuel: Grassroots Motorsports Understanding Corner Weights. track are left turns then having more weight on the Right Front and Left Rear
Crossweight is of no concern to the track officials. If you do have adjustable end
of the scale to take a reading. You've mentioned "dead struts" a couple of times - what do you mean by that? I'm not saying you get what you pay for with race scales but there is a reason I went with longacre. If the car feels loose on corner entry, lower the left track bar. This also coveys other advantages, the short shock travel means that it can be shorter and lighter. end-link into the anti-roll bar's hole. works well. These are your current calculated weights: Left Weight =
If it slows to 100rpm, the outside wheel will spin at 300rpm. springs settled over the first 3 months. If you think you need to make crossweight changes, remember the amount of change per adjuster number, in our case it was 7/8 turns per percent of crossweight at the right sides (left sides again are times the multiplier), and make even percent changes, such as a half percent or whole percent. Wedge Delta and what values work best for certain tracks and conditions
I'm off by 0.1% (see numbers on left side of the spreadsheet). 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. It's stuff closer to 60/40 or 40/60 where you need to stray from crossweighting. Ah, OK, thanks for the clarification. Changing the ride height at any corner will change the cross-weight percentage. Once you have returned the wheel corresponding to the spring change back to its measurement, the other wheel measurements will be OK. 3.
The Science Behind Dirt Late Model Suspension Setup Adjustable end links are more
(adsbygoogle = window.adsbygoogle || []).push({}); If you prefer Microsoft Excel a Corner Weight spreadsheet is available for download here
45.
Circle Track Analyzer - Performance Trends the front ramps then jack up the rear and lower it onto the rear scales.
Steve Smith Autosports - Tech Tips Wedge Delta is equal to (Right
very close to ideal.
Corner weights-cross weights - TenTenths Motorsport Forum 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. I just run higher pressure for the street, I feel mine is pretty close as is. This keeps the ride heights as close to ideal as possible. Many electronic scales will perform the calculations for you. Remember that this is a sample car, so don't use these numbers, but do use this method. in the driver's seat to load the suspension. Corner Weight Calculator This is used to calculate the corner weight and Wedge. Motor: 550 or 540 motors only. For pure race cars this isnt a consideration. Always record the cross-weights and ride heights for reference at the race track in case changes are needed. turns. This was my first adjustment: Four turns of positive coil
turns to the Right Rear: I still needed more weight on the LF and RR so I added +4 to the LF: I still needed more so I added +2 to the RR and drove the
57.5" front and 59.625" rear. oval racing world and is simply another word for Cross Weight.