At the end of the day, the springs where rated. Bump Steer Gauges & Set Up Tools; Stagger Tools; Tire Temp Gauges; Toe Tools; Turn Plates; . Several top-level teams have found that this movement actually causes the car to handle inconsistently. At Apex Customs Phoenix our expert technicians understand that every suspension package is . One should use the same free height, but change rates. Increase the Rear Brake Bias. So testing for the fastest lap does not guarantee success. Here is an explanation of balance related to the dynamics of the race car. 5. Tapered end leaves have a gradual decrease in thickness on each end. Drag Racing Front Spring Tec. As we use the left-front tire more and more, the negative results of Ackermann become more apparent. The actual total spring change instead of 200#s is 410#, over 100% more or twice the spring change desired. PDF By Bob Bolles, Circle Track Magazine - Longacre Racing LEGEND: May use 1 or 2 90/10 Dampening ShocksOver Rear End to Tighten Car on Corner Entry. We have continually pressed these issues because of the extreme importance they have. When running balanced setups that work the left-front tire, we must eliminate most of the Ackermann. For example, if the main leaves are the same length and one spring has more arch, the spring with the most arch will have a stiffer installed rate. Each suspension system desires to do its own thing when lateral forces are introduced from the car going through the turns. If we are loose going into the corner, the LR shock may be too stiff in rebound or the RF shock may be too soft in compression, which transfers load off the LR tire on initial entry under hard braking. Mono Leaf Spring Consists of one main leaf where the materials width and thickness are constant. Parabolic Single Leaf Consists of one main leaf with a tapered thickness. As the front brakes are applied, the caliper grabs the rotor and the motion of the wheel/rotor tries to rotate the spindle. Driving style plays a major role in the life of a leaf spring. When the car is jacked up during a pit stop for a tire change, the suspension may become completely unloaded leaving the coil spring to rotate in the spring bucket. If one corner of the car is shocked stiff, then as that corner desires to move in compression, more load will be retained by that corner as well as the opposite diagonal corner of the car during the compression cycle only. Leaves that are tapered on the ends are generally used for mass production applications which do not require the close tolerances and consistency in the spring rate that racers demand. Make small adjustments, about one half of one percent. I don't get too many reports of continual, repeated wins and successes. Some manufactures even feel and state that racers should monitor a springs free height instead of its rate. Decrease both Front Spring Rates. Furthermore, the fiberglass spring is susceptible to damage from rocks and debris. Leaf springs possess many desirable suspension features, such as dampening, forward bite, roll over steer, high anti-squat percentage, and high lateral stiffness. That is an effect that causes a decrease in the amount of toe-out as we steer and can actually cause the front tires to end up with toe-in if the effect is severe. I have talked to racers who run on tracks that require 1.75 to 2.00 inches of stagger. This insures properly made springs, guaranteed arch tolerances, access to complete labs for testing and research with technical racing experts to understand your requirements. (2.) The shorter upper A-arm decreases in length faster than the lower control arm causing camber loss. When it happens on the right front, the chassis will gain bite. Antisquat results from the third link trying to straighten out, or become more horizontal as the car accelerates and the rear end desires to rotate. Add to cart Details. We mostly use the sway bar to tune for traction off the corners. Roughly 8-10 degrees of third link angle is sufficient to promote antisquat and not hurt your corner entry. If this component on your car is not right, then the whole car will suffer, no matter what else you do. This tends to tighten the car on corner entry and through the middle of the corner. A very good set of adjustable shocks came with the car also and that helped us when it came time to do the setup. The upper BJ is trying to be forced in a forward direction and the lower BJ is trying to be forced in a rearward direction. Both of these are necessary components that will be needed to win championships. In testing conventional setups over a five-year period, it was discovered that most tires want no change in camber relative to the racetrack surface as the car dives and rolls. Performance Driving | Radford Racing School Other helpful hints are available from our technical experts. In the common asphalt setups of today, where we use a larger sway bar and softer springs (BBSS), the presence of Ackermann effect could be more detrimental. Ask your supplier what materials the spring consists of. The basics remain the same, but with a few critical adjustments. When it happens on the left front, the chassis will lose bite. In addition, the leaf spring suspension is more forgiving on chassis set-up errors. Circle Track FAQs - QA1 Long gone are the days of saying that the MC is not important. It has been found that the misalignment of your tires/wheels presents serious drawbacks to a finely tuned chassis and setup. This would mean we could align the driveshaft from a side view inline with the tranny shaft and the pinion shaft with no angular deflection. The amount of resistance is directly related to the degree of side view angle we put in our control arms and the amount of brake force used. Some teams refuse to run sufficient stagger to match the radius and banking of the racetrack. Leaf-Spring Systems - The leaf-spring rear suspension system locates the rear-end fore and aft, as well as laterally using the leafs. It should help your 60' times by letting the rear squat more at the line before the suspension loads up. This is very "old school" but when applied with a balanced setup, very effective. When they are working together, the car is well on the way to a balanced state. A shackle with a 3 degree layback incorporates a stiffer installed rate than a shackle at 25 degrees layback. The left side suspension usually is designed with about half the angle of the right side in a conventional design. Higher arch springs tend to work better on the dirt tracks whereas the lower arch springs perform better on the asphalt tracks. It just won't work. Does it have actual print outs of each spring (data sheets)? Decrease the Split on the Rear Panhard Bar Heights. The following is a list of things that can make the car not want to turn or make the car loose. The front end should always be weighed to ensure proper spring selection. If those desired angles are different, then we term the setup unbalanced. If the front geometry is not designed correctly, then as the car dives and rolls, the RF camber relative to the racing surface will change and the tire will lose grip. ASPHALT MODIFIED (Standard 3 Point and 4-Link Cars) 2006 Set-Up and Technical Guide. 7. Multi-Leaf springs used for racing should have a clench clip type system. All of theGOLD COILSare packaged with dyno sheets detailing the dynamic rate in a graphical form as well as numerical form. The disadvantages of banding clips with rubber linings is that the rubber will absorb grease and brake fluids leading to deterioration of the components. Most companies incorporate a metal tag denoting the theoretical rate of each spring. LIT-719 80292 C7 Corvette Radiator. With a Detroit Locker, or similar differential, the axles will unlock going in and through the middle and lock up on exit while under power. That is fine as a goal, but what we really want is both balanced and neutral. Since the braking forces are in the opposite direction, there is a serious resistant force created which helps prevent the front suspension from moving in compression too quickly while braking. The reason I say that with confidence, is because I have gone up against more aero efficient cars with setups and body configurations that were aero-deficient and still out ran them. Adding or removing as little as 50 pounds can also make a difference. This induces rear steer when the car squats on exit. The disadvantage of this style spring is that the spring rate has a progression in spring rate. Tire temperatures can tell a lot about the setup and where we need to look to fix the setup balance problem. Mid-turn handling problems are caused by a car that is either tight or loose. Moreover, accurate spring changes will allow teams to be more progressive in their test sessions and eventually reflect in their qualifying efforts and then onto the race. HOPEFULLY THE INFORMATION CONTAINED IN THE TECHNICAL AREA HAS BEEN HELPFUL. Disc brake spacers will further impact the height. It's been three years since we discussed the subject of handling fixes. Cars with a lower CG should have a MC that ends up farther to the left side of the scale than would cars with a higher CG. Installing a torque device combined with these types of suspensions will cause the wrap-up rate to be excessive. Designing a spring also requires considering the wire size, O.D., I.D., free height, compressed height and static loads that are to be expected on each spring. DESIGN: Most coil spring failure is directly related to the design of the spring. That would be only on the r/r,you could toe the l/r out and the r/r in if the car needed it.If your housing has 1/16 toe out on the r/r you might need to shorten the wheelbase 3/4 to 1'' to get some toe in in the r/r.With r/r toe in the thrust angle of the tire is pointing toward the center of the car.When you pick up the throttle the r/r drives toward the infield and keeps the car tight letting you apply more power. A car can appear to be loose even though it is tight. Another negative effect of forged end springs is the fact that the chassis settings may change. The current spring is tagged 2,000#; however, the unknown actual rate is 1,900#s. As a result, the car will have unpredictable chassis characteristics and may cause premature tire wear. Then all you have to do is maintain that balance throughout the season and that means resisting making changes that take you outside that envelope. Furthermore, the crew made unnecessary changes, wasted valuable time, resulting in wear and tear on the engine, tires and other components. This induces less rear steer when the car squats on exit. A common misconception is that arch affects free spring rate, which it does not. Therefore, decreasing its long term effectiveness and life. Reduce the crossweight in a tight car and increase the crossweight percentage in a loose car. LANDRUM PERFORMANCE SPRINGSmakes no guarantees that these charts will be suitable for each racers needs. Installing the leaf spring directly to a fixed axle seat (no upper or lower rubber mounted pads which are common on GMs) will increase the overall spring rate, wrap-up rate and lateral rate, as well as the braking rate. When all three phases are balanced, work on driver finesse and practice passing maneuvers running high and low off the corners. LANDRUM SPRING has the proper mixture of chrome vanadium, carbon, manganese, silicon, nickel, molybdenum and tungsten. Brake Bias Let's stay with the circle track lingo.