Wheel alignment: Camber. That is my theory on caster angles vs. larger tires, whether that is the correct reason or not, I can’t really prove, but the fact is too much caster with big tires can cause death wobble. Your email address will not be published. For these drivers, too much positive caster can deliver over responsiveness, handling nervousness at higher speeds, more feedback from road disturbances and more steering effort at low speeds. The more positive the caster, the more cross weight there is being removed. If you've ever pushed a shopping cart then you've felt the effects of negative caster on the front wheels. Banked corners at NASCAR oval tracks require asymmetrical camber setups with positive camber on the LF tire and considerable negative camber on the RF (outer) tire. As for too negative of an angle, you've seen those results, again, scary. I have the caster at +4.8° and the Camber at -0.5° On the left adjustment is limited. It is done by placing the front wheels of your car on some turning plates that have the scale set to 0 degrees. Caster. For a normal car you typically want to maintain a slight amount of negative camber (0.5 - 1°) to have a good balance of cornering grip, braking grip, and tire wear. A good alignment will make your car handle, brake, and accelerate better for very little investment. The angle between the two lines is the caster angle of that wheel. Bias ply tires react very differently to camber angle due to the differences in their construction compared to radials. As you work on the problem keep in mind that the role of positive caster in any vehicle is to create increased stability. Anti Lift Kits – Ensuring more compliant suspension that delivers improved front end grip with added caster gains. Click here The front camber will mimic a road race setup at around 3 - 4° to maximize lateral grip ("side bite"). If the tire is perfectly vertical in relation to the road surface, its camber is ±0°, or zero camber. Finally the vertical centre line of the wheel must be drawn. With caster maxed out now I get closer to the other side, +5.0 caster, with -1.95 camber. If the driver feels like the steering is beginning to get shaky or wander at high speed then increasing the positive caster will give the wheels a higher self-aligning torque and will make the car more stable at high speed giving the driver more confidence in the car making them push harder and faster. Anti Lift Kits – Ensuring more compliant suspension that delivers improved front end grip with added caster gains. It is important to note that some might argue that you can not have too much positive caster. As far as we know, all four wheel vehicles are designed with positive caster … Positive caster angles run between 3 - 5° on modern vehicles. Excessive heating on the inner or outer third of the tire can be indicative of improper camber angle, although not conclusively. Thread in 'Technical Questions' started by Mike@TDSW, Feb 22, 2011. If the car is beginning to understeer mid corner due to too much negative camber being present on the outside wheel then reducing the positive caster will reduce the camber gain when cornering. Here's a couple more examples: The ideal amount of camber for handling performance comes from a couple of variables: Put simply, the amount of suspension travel and how much camber is gained as the suspension travels will dictate how much static camber you need to run. When you turn a car left with positive caster the LF rises while the RF drops. Negative camber is what counteracts the tendency of the inside wheel during a turn to lean out from the centre of the vehicle. Positively Positive. I had that problem on a Cherokee and it was a combination of too much caster and bushing play on the arms. Quick fact: While some positive or negative camber is good, too much of either is bad. At proper camber settings the tire will exhibit stable and symmetrical temperatures across the tire surface during cornering. This makes the tires want to push inward, which acts to improve straight line stability of the car as its traveling down the road, particularly at high speed (highway). The first stage of adjusting and tuning your caster angle is to first measure and understand what your vehicle currently has. 1993 YJ, AX15, 4.0L, 8.8 LSD w/3.73's, Lock-rite locker in front, S.O.A. If the rear is higher than its designated trim height, the … In high end motorsport where the suspension components are custom made and are designed to be adjustable the use of shim packs is often used on the hubs. The angle between these two lines is the caster angle of that wheel. The benefit of positive camber on these vehicles is that you don’t need to use much effort when steering them. It's important to have a healthy balance to ensure good overall performance. All of them are aftermarket or specialist motorsport parts as it is very rare that a road car comes with caster adjustment as standard. Positive caster angles run between 3 - 5° on modern vehicles. Too little caster can also make steering overly sensitive at high speeds and reduce wheel returnability after completing a turn. Proper camber (along with toe and caster) make sure that the tyre tread surface is as flat as possible on the road surface. Less negative camber (until the tire is perpendicular to the road at zero camber) typically will reduce the cornering ability, but results in more even wear. caster. The benefit of positive camber on these vehicles is that you don’t need to use much effort when steering them. Worn ball joints, strut mount, tie rod, and other wheel-suspension parts may contribute to camber misalignment. There a few ways that caster can be adjusted on car. With less caster (say 4 … If you have too much positive caster, the vehicle will be harder to turn. Some have the damper location offset rearward to increase the caster angle of the car. Once again this position is fixed as is not adjustable once installed. Vehicles that specify high positive caster usually have a steering dampener attached to … If you aren’t using enough, over time the outside edge of the tire will be visibly more worn than the inside. A second line is then drawn vertically down the centre line of the wheel. If you are not running power steering, a caster setting of 3 - 4° is a good setup to reduce the weight of the steering and maintain the benefits of positive caster angle. For a more performance oriented setup on a MacPherson strut you can add a degree or two to have more favorable camber gain at high steering angles. Toe-in is when the leading part of the tire is turned inwards towards the center of the car. If both sides are equal but too positive, the steering can be heavy. This gives a good mix of highway stability and steering feel. Road conditions can also demand more or less camber. Another way to adjust the caster of a car with a MacPherson strut set up is to install offset top mounts on the coil over. (too much positive camber). Too much inward (negative camber) or outward (positive camber) tilt, indicates improper alignment. The majority of these front-wheel-drive vehicles do not allow their positive cambers to be adjusted. However, it is better to reduce the static negative camber instead to combat this unless the camber can’t be changed for another reason. This allows the wishbone to be spaced rearward of the hub, increasing the caster angle in adjustable increments. The high speed stability of the car will also be greatly improved in a straight line. When looking at the vehicle from the front or rear, you will see the profile of the wheel and tire. I thought it was subframe bushes as … I was able to get 4-5* positive caster with 1/2* negative camber. What is camber, caster, and toe? Too little positive caster might make steering touchy at high speeds and diminish wheel returnability when the car is coming out of a turn. Camber is a measurement of the centerline of your wheel/tire relative to the road surface. Different suspension designs will result in varied camber gain curves, and even two similar designs can result in widely varied camber gain. Head over to our contact page and send us an email with your ideas, comments, or questions. Dallara World Series Single Seater – Under The Skin, Coilovers – Installing and Setting Ride Height Correctly, Helper Springs and Tender Springs – The Difference, Tyre Failure – Graining, Tearing, Blistering and Wearing, https://www.youtube.com/watch?v=_Ksbfn40adA, Turning plates and a digital or bubble camber/caster gauge. Good luck with the conversion. With a more positive caster angle, the wheels will toe in. Therefore if the driver feels like they are having to manually steer the car out of a corner and are putting in too much effort to bring the car back to a straight line then increasing the caster will help this. For example, a solid axle has no camber gain, but an asymmetrical double wishbone may gain 2° of negative camber with 2" (50mm) of suspension travel. For example, a double wishbone setup can generate significantly more camber gain by shortening the upper control arm. This method is not adjustable once installed and simply increases the fixed caster of the car. There are two main ways to measure your caster angle: The first technique is the quickest and fastest way to measure caster and can also be done trackside which is especially useful if you are tuning your caster on a track day or whilst racing. Running too much positive caster can cause some issues due to the weight jacking effects and the negative camber gains that caster produces. This is generally only found on older vehicles due to tire technology, chassis dynamics, and other reasons. But if you have a good amount of positive caster gain in bump, & a fair amount of travel in dive, then less camber gain works well. With a car with MacPherson strut suspension on the front wheels the method of drawing the caster angle is slightly different. jim . Dynamic camber is the static camber plus or minus the "camber gain." Your vehicle may prefer more or less camber. I think its going to wear the outside of the tires prematurely. This is a big topic that I don't have a ton of time to get into at the moment, but hopefully those comments are helpful. Too much inward (negative camber) or outward (positive camber) ... More positive caster adds a little bit of weight/feel on the steering wheel and stabilizes the wheel at speed. In the case of a MacPherson strut system this can be in the form of an adjustable tension rod that holds the lower arm forwards or backwards in the wheel arch. However, just like with camber, vehicle pull is not caused by too much or too little caster, but by side to side imbalance. We will never spam, sell, or do annoying things with it ... ever. As far as we know, all four wheel vehicles are designed with positive caster (forks out towards the front at the bottom). The most perceptible effect of caster is how much the steering wheel wants to 'return to center' while turning. The best I can get is caster +3 and the camber at -0.5. Hopefully, these articles will help. They went too far the other way, and it is wearing the outside pretty quickly. Turning the wheel lifts the front end a little, and releasing the wheel allows the weight of the vehicle to push back down, assisting return to center. As you increase positive caster the steering will get heavier also, but with modern power steering systems this is rarely a problem. As a rough guide, here's a list of camber settings for various suspension layouts and vehicles. Toe is the measure of how far inward or outward the leading edge of the tire is facing, when viewed from the top. As you increase positive caster the steering will get heavier also, but with modern power steering systems this is rarely a problem. Loose gravel and wet pavement both limit the amount of overall tire grip available, which necessitates less static camber. Vehicles with too much positive caster can be prone to understeer, so most modern vehicles don’t have a caster greater than 3 to 5 degrees. This is rarely ever seen on a road car since it will reduce road handling capability. Feb 27, 2020 at 12:44 PM #2 #2. Consequently, too much positive camber causes wear on the outside edge. Having some odd driving issues with my M3 and cant quite get my head around it. Some of the most popular ways of adjusting caster are: One way to adjust caster is with an adjustable arm. and the high steering angles they generate can produce quite a bit of camber change at full lock. It increases traction by maximizing a tire’s friction to the ground, helping the vehicle to stay on the ground. This is because KPI geometry also creates a jacking effect but in the opposite direction to that of caster. Too much positive camber in 68 RR. We respect your inbox and send only 1 - 4 emails per month. Later, I took it to place that had old Bear alignment equipment to see if they could adjust that out. Camber . Sounds more like your tires are not balanced correctly. Budget to Premium Coilovers – Whats The Real Difference? The vehicle in the chart is within specifications for camber and toe but has excessive positive caster. Too much positive camber in 68 RR. As you work on the problem keep in mind that the role of positive caster in any vehicle is to create increased stability. One way that the jacking effects of caster can be counter-acted is by adjusting the King Pin Inclination geometry at the front wheels. For most cars this is around 2 - 3° of negative camber. Effects of too much Caster? If your camber is out, you’ll get tyre wear. A large positive camber setting (wheel facing forward of axis) is good for high speed stability but can make it more difficult for turning the steering, excessive amounts will increase tire wear. Then the lower mounting point at the hub of the lower wishbone must be located and drawn. Do you think it’s possible a high speed drive line vibration is caused by too much positive caster? This is because if the driver is not physically capable of turning the wheel mid race then their racing line will become sloppy and will impede their lap times. You'll even save money by reducing tire wear with a simple correction to the camber and toe. The alignment specs do allow to bring the camber down. Camber. Caster is the measure of how far forward or behind the steering axis is to the verticle axis, viewed from the side. Ideally the drive shaft would be near in-line with the pinion angle. One common way to adjust caster is to install an offset caster bush. This gives a good mix of highway stability and steering feel. In this case, a line is drawn down the length of the coil over down to the ground. In special situations, such as NASCAR, positive camber will be applied to handle heavy amounts of track embankment. Generally you want as much positive caster as you can reasonably get so long as the car is equipped with power steering. Joined: Jun 30, 2016 Member: #3727 Messages: 1,409 Gender: Male Eugene, Oregon Vehicle: 2017 Tundra 5.7 … Increasing positive caster will increase the jacking effect during cornering. Your email address will not be published. You don't want a ton of camber when your car dives under braking for example. Caster is said to be positive if the line slopes towards the rear of the vehicle at the top, and negative if the line slopes towards the front. Too much inward (negative camber) or outward (positive camber) tilt, indicates improper alignment. I have the caster at +4.8° and the Camber at -0.5° On the left adjustment is limited. The re-centering speed of the wheel will also be increase with increased positive caster. .7 deg gain per inch of bump is what I've heard too. In a road car, this would mean that the top of the coilover would be pushed towards the rear of the car. Improper camber can make the tyre wear faster either on the outside or inner side and may also cause the vehicle to pull to the side that has the most camber angle. 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Your truck to increases traction by maximizing a tire ’ s friction to weight..., shims are placed between the wishbone to be used to run high levels of caster is when leading! On tire wear 4° to maximize lateral grip ( `` side bite )... Good overall performance needs depending on their suspension design and geometry a rough,... Get my head around it arm and added shims to the camber -0.5. Only found on older vehicles can have too much positive caster unique needs depending on their suspension design geometry. Tilt inwards ) causes tread and tire wear a double wishbone setup can generate significantly more gain... They generate can produce quite a bit easier will be harder to turn and generally.