It is this same torque that requires more effort to turn the wheel. Caster is the forward or backward tilt of the steering axis viewed from the side of the vehicle. Once you've done your first alignment, you'll realize how easy it is and that you've now climbed another rung on the gearhead master mechanic's ladder. .. Camber. Vehicles that specify high positive caster usually have a steering dampener attached to reduce any adverse effects.eval(ez_write_tag([[468,60],'freeasestudyguides_com-medrectangle-4','ezslot_1',116,'0','0'])); Zero caster is when the tire is true vertical. If you don't have a set of turn plates you can use the angles machined on the corners of the gauge as a reference. Caster is a little less obvious. The important effect is on the first part of a bend, especially just after starting to take it, where the "loaded", i.e. Cars equipped with an upper control arm are generally mounted with a cross-shaft. More likely than not, a tad less. 1 What happens when there is an increase in the caster angle? The usual spec is slight toe-in to compensate for angular pressure that forces each tire outward as the car rolls down the road. First of all you have to measure the caster of your vehicle.Several caster gage are available in market. See Adjusting Jeep CJ Caster. Are you accounting for the angle of the ground you are on? This will kill the measurement if they aren't. Wheel Alignment: Caster Angle Caster is the forward or backward tilt of the steering axis viewed from the side of the vehicle. On early Mustangs, for example, Ford employed a strut rod attached to the lower control arm that can be moved either in or out to adjust the caster. Shortening the rod (moving the lower control arm forward) increases positive caster by moving the bottom of the spindle forward. An interesting point is that the 20-degree turn-in and turn-out figure is not critical. Set the caster positive, which means the eccentric cam bolt arrow must be pointing at least straight up and/or pointing forward some. If the car still pulls with accurate alignments, try switching tires side to side to eliminate a bad tire as a possible cause. See: Installing camber adjusting upper ball joint sleeves Personally, we prefer the shim, it … If more movement is needed in either direction, offset shafts are sometimes available. We learned that every time you adjust the toe (without turn plates), you must push the car backward and then forward roughly 10 feet. The opposite situation is negative caster, where the top of the spindle is tilted forward past its vertical centerline. This is a serious tire-wear angle that has a huge impact on vehicle handling in a corner with minimal effect on straight-line driving. 3-4 degrees should do you fine. Conversely, if the tops of the tires are tilted outward, that's positive camber. We also used a set of aluminum toe plates from Intercomp to measure toe. This excessive positive caster will cause a shimmy at higher speeds and excessive steering wheel snapback. Then put the angle finder on it and run. Ugh! Look down at your feet and point your toes inward with your heels angled outward. The screw can be adjusted to move the wheel forwards or backwards adjusting the caster angle. With the bubble gauge installed on the hub, turn the tire inboard 20 degrees and level the gauge. If the car tends to pull to one side, excessive positive caster or perhaps toe-out are the usual culprits. No - caster is not adjustable on a stock set-up. Keep in mind that you're using the same shims to adjust caster as you are to adjust camber. Positive caster creates an aligning torque by positioning a portion of vehicle weight behind the tire, which helps position the tire straight ahead. ... caster setting. This will be especially important the next time you're stranded on a lost Pacific island and the cannibals offer to crown you king if you can dial in the right caster and camber on their Pro Bamboo car. Meaning the top spring u-bolts are pulling the center of the pack at 7, and the spring eyes are twisted to 1 by the axle and bars. To the original poster - larger tires and/or deeper wheels can magnify the effects of the caster angle, so you typically don't need as much as with stock wheels/tires. By clicking Sign Up, you agree to the  Terms of Use. More realistically, what if you want to test your car at the dragstrip after a suspension rebuild, but the alignment shop can only fit you in a week from Wednesday? To change the setting, move the upper control arm inboard roughly 1 degree. A safe starting point for caster is 2 to 3 degrees of positive caster. Adjusting the lowers (only) will push the wheel forward in the opening. The camber of the vehicle determines how much the wheels are tilted either inside or out. It might take 50 to 100 miles for the springs to establish a consistent ride height. They run a large amount of positive caster to make the cart track straight without wandering. The control arms, top and bottom yellow parts, are usually adjusted by cam bolts or eccentric-washer bolts to effect camber and caster changes. Toe is always set last because adjusting camber or caster moves the control arms, and that changes the toe. We've experimented in the past with digital angle finders, which work very well but require math to calculate caster angle. Once you've established the camber, caster is the next angle to check. You might actually find this stuff fascinating-we do... Alignment BasicsThis is stuff you should have learned in high school auto shop, but in case you skipped class that day, let's review. Check and adjust toe after adjusting the camber or caster angle. Check out the caster illustration to help understand this alignment characteristic. This allows you to perform the 20-degree turn-in and turn-out for measuring caster. Positive caster is achieved by either adding shims to the rear bolt or removing shims from the front attachment point for the upper control arm. Now,for adjusting the caster angle several methods are available. There are plenty of sources that claim you need a set of turn plates to do an alignment correctly, but while handy, they are not essential. Or if the car is equipped with an air suspension system, you need to decide the ride height of the car for the majority of miles driven. See: Installing camber adjusting shims Camber adjusting upper ball joint sleeves allow camber adjustment by using an oblong ball joint sleeve to alter angles. We'll cover the basics and get into how to set your own alignment at home with a few simple tools that any good car crafter should have in his toolbox. DIY Alignment Guide - Caster Adjustments Explained. I shot for 6-8 degrees when I set mine up, but I … Let's say the gauge reads 1/2 degree positive camber. Positive Caster The vehicle in the chart is within specifications for camber and toe but has excessive positive caster. Sadly, you will have to spend $$ to get caster/camber plates. Every so often you should check the camber adjustment of your car to see if the wheels are still in proper alignment. It is the angle between the pivot line (in a car an imaginary line that runs through the center of the upper ball joint to the center of the lower ball joint) and vertical. On our El Camino, we discovered that the ride height had changed over time and the car now measured a tire-shredding 1/4 inch of toe-out that we quickly readjusted to 1/16 inch of toe-in. Vehicles with SLA suspensions use the upper and lower ball joints to create the angle, and those with struts use the center of the upper strut mount and the lower ball joint as the angle. You need to adjust all 4 bars to get the caster and location correct. Vehicles with SLA suspensions use the upper and lower ball joints to create the angle, and those with struts use the center of the upper strut mount and the lower ball joint as the angle. Turn the wheels until the angle is parallel to the side of … The camber adjustment of your wheels is an important measurement to keep an eye on. Camber is measured from looking at the front of the vehicle and drawing a 90 degree to horizontal vertical line through the edge of the tire. Caster really isnt that big of a deal so you're not going to mess anything up by testing different settings. Caster, which is also referred to as caster angle, is the top to bottom angle of the steering axis and suspension components as they meet the wheel. Keep in mind that you should align a typical drag race car with the front end raised approximately 1 inch to simulate the way the car will run down the track. Now turn the tire 20 degrees out and the gauge will read … Most street automotive front suspensions offer three separate adjustments to properly position the front tires: camber, caster, and toe. Caster is the angle or difference in upper and lower ball joints per se. If you look at a bicycle from the side, the top of the spindle is angled rearward toward the rider. Caster Caster is the amount of angle that the spindle has in relation to the vertical centerline of the wheel. Once you have set the camber and caster, you can adjust the toe. If the pinion is pointed towards the ground, and you don't have enough caster then you will have to break the knuckles loose and redo the caster. Attached to the aluminum angle is a bubble level with an adjusting knob. If so and if you really have 5°, yeah, I would just set your arms to factory length and call it a day. Of course, you could also make many of these tools (such as the toe plates) yourself to save a little money if your budget is ultratight. Most bubble gauges are equipped with a magnetic adapter that allows you to place the gauge on the brake hub. Negative caster reduces steering effort because the weight moves forward of the spindle vertical center but also detracts from high-speed stability. Anytime the ride height changes, camber, caster, and toe will also vary. This will probably affect camber, so you will want to check it again after modifying the caster. Camber. When we did our first home alignment, this was where we screwed up. Now turn the tire 20 degrees out and the gauge will read the amount of positive or negative caster. There are several methods to adjust camber, depending on the vehicle and its suspension. Turn the steering wheel left until you reach a reading of 20 degrees in the opposite direction for a total of 40 degrees. An example of caster in action is the front wheels on a shopping cart. If the lower joint is more forward then you will have negative caster. Placing extra … The best procedure is to move the left and right side adjusters the same amount until you get the desired toe-in. If the tops of the tires are tilted inward, it is called negative camber. Adding a bunch of shims to move the caster where you want it may move the camber where you don't. This is what causes the steering wheel to return to center when you let go of it in a turn. Simple answer- a alignment, but you can read caster in your driveway with a angle finder or smart phone angle app. I've done alignments back in school but not a jeep mostly big rigs. Most vehicles have positive caster because it provides greater feel and stability, helps the wheels track straight, and provides steering wheel return after turning. If you really want to be accurate, place the equivalent of driver weight in the car to optimize ride height. The Alternative Rocker - Taurus SHO V6-powered, Explorer-framed, TTB-front, RCV'd, YJ … It has a fixed range in which it works.This is a magnetic based gage. If you can only afford one tool, go with the bubble gauge. Refer to the above recommendations for how much caster … If you were changing the pinion angle on the front axle (tipping) it could change the caster but I'm not 100% sure. The most common way to adjust your caster angle involves adding or removing shims to obtain the proper angle. Toe is perhaps the easiest to understand. This loads the front tires to produce the most accurate readings. We've also included typical specs for a single-purpose drag car. Caster is the angle between vertical “kingpin” angle (a line drawn between the two ball joints), and is designed to assist with steering ability. Positive caster is when the lower axis is toward the front of the vehicle, and the upper pivot is leaning away from the front toward the rear. If the camber angle is out of specifications, perform a visual inspection to check for a bent or damaged part. On top of the knob are a series of eight lines. Using the center caster adjustment knob underneath the gauge, zero the caster reading. Plus, you'll have another bitchin' tool to upgrade your toolbox. Substitute front tires for your feet and the effect is the same. You can add or remove shims from the rear bolt or where the upper control arm attaches to the hub. Even if you don't intend on becoming the neighborhood chassis specialist, at least you can talk intelligently when the bench racing turns to camber and caster. Next. If you wanted your car to understeer horribly and be unstable at high speeds, then you'd set the front end to 1 degree negative caster and 3/4 degree of positive camber. Both of these situations are significant tire-wearing angles, so setting toe is critical to handling and tire life. Adjusting Caster To adjust the amount of caster … CASTER: the angle of pivot viewed from the side relative to straight up and down.. One way to adjust caster is with an adjustable arm. This is an extreme example of positive caster that creates high-speed stability-the effect that allows the rider to let go of the handlebars while the bike tracks straight. Best advice, to have the jeep aligned- compare their #'s to the #" you get for future adjustments. To use the tool, you first adjust the pegs to suit your wheel diameter. It's not surprising that this is called toe-in. What is important is moving the tire the same number of degrees in and out. Some teams use one edge of the bubble so that reading the angle is more accurate than trying to estimate the center of the bubble. After adjusting all three settings, take the car out for a leisurely testdrive and pay attention to how it reacts to different pavement and driving situations. Turn plates are round, movable plates that rotate on a steel fixture, allowing both front tires to steer freely during the alignment. As the front end raises, the caster angle becomes negative, and as the front suspension compresses, caster gets more positive. Stock suspensions may feature cam bolts, eccentric washer bolts, turn-buckle joints, or shim adjustments. Since this is Car Craft, where do-it-yourself rules, we just know you secretly harbor an intense desire to get familiar with the basics of alignment and at least know what all those obscure terms mean. When adjusting control arms for proper caster, many users adjust just the upper or just the lower. To read CASTER first turn the wheels 20º to the right when setting the RF and to the left when setting LF. Just do it yourself and you'll know it's right. Adjusting the camber angle on a vehicle affects the total toe. You may need to adjust the Heim Joints by turning one in or out more than the other to get the appropriate setting. If the pinion angle reads 4*, we KNOW the caster is at 2*. If you were to simply install a coil spacer for a few easy inches of lift, your caster angle would be on the low side of its acceptable range which will have a negative impact on straight line handling. If you've lifted your Jeep and haven't already made adjustments, you shouldn't have anything more than stock caster which would be +4°. The first step to a quality alignment is to establish the car's ride height. Toe-out is the worse of the two angles, since a car with excessive toe-out will have skittish steering, often darting to either side of the road very easily. This creates a grocery cart-like situation, where the wheel centerline is behind the spindle centerline. Camber is the inward or outward lean of the tire from vertical, while toe is the inward or outward orientation of … I sacrifice caster to get proper camber. Front-End Alignment SpecsSince this story is not aimed at a specific vehicle, we'll fling you a set of generic alignment specs that will work for most '60s street-driven vehicles. Step 5 Once the ride height is set, the next step is to check the camber setting. If you've just finished a front suspension upgrade with new springs, for example, the ride height will change once the springs settle. Camber is a tire-wearing adjustment, caster isn't. Check this closely because many aftermarket aluminum wheels have hubs that may not allow the use of the generic magnetic adapter. Negative caster is when the lower pivot point (ball joint) is toward the back of the vehicle compared to the upper pivot. Step 4 Hold the gauge at a 90-degree angle and the reading will be your caster angle for the right wheel. Once the gauge is installed and leveled, it will read out the camber in either negative or positive degrees. Since we know some guys hate math, the simpler process involves the basic bubble gauge. They might have an angled shim at top, or modified the crossmember angle. 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. Virtually all vehicles employ positive caster, but excessive amounts can lead to camber problems, since these two angles directly affect each other. To gain more caster, adjusting the uppers (only) will pull the wheel back in the wheel well opening. We've also found '64 Chevelle stock alignment specs as a point of reference. If you are lucky enough to own several cars, you could easily recoup the typical $50.00 alignment charge in only three jobs. The 20-degree figure is popular because the more degrees the wheel moves, the more accurate the measurement. That alone is worth the price of admission. Inserting an equal number of shims between the framerail and the cross-shaft on both mounting bolts moves the upper control arm inboard on both studs and creates the necessary negative camber. Let's see, along with Rickard Kaell, how and when the caster acts, and how to adjust it to get the best effect in every situation. Big rigs use caster shims on the front axle. © 2020 Hot Rod | MOTOR TREND GROUP, LLC. This technology has been around almost as long as the automobile, and if you pay attention, you can do a great alignment with almost any bubble gauge. What Tools Will You Need?Like any other job, the better the tools, the more accurate the result. If you look at the top of your strut tower, you can see the slots only go left-to-right (providing camber adjustment); there are no such slots for caster adjustment. Your information will be collected and used in accordance with our  Privacy Policy. Replace the damper pinch bolts with the adjusting bolts (A), and adjust the camber angle. An improper caster angle can make flat towing dangerous and coming out of sharp corners exciting due to the wheel not coming back to center. Most domestic cars use left- and righthand threads with a threaded sleeve and locking nuts to prevent the adjustment from changing. The opposite, toe-out, is where the leading edges of the front tires are angled outward. However, the method that the cart uses (displacement caster) is different than how your car develops its caster angle (angled pivot), but the effect is the same. A 2-inch front-end rise changed the camber by almost 2 degrees on our Chevelle, which would also affect the toe and can cause tire scrub. We found a set of used turn plates at the swap meet for $30.00, which is a super price because new ones can cost $600.00 or more. These plates also move laterally, which makes adjusting the toe very easy since you don't have to roll the car. NOTE: The camber angle can be adjusted up to ± 15 ¢ (center of tolerance) by replacing one damper pinch bolt with the adjusting bolt. Camber is easy to visualize. We found a great billet aluminum bubble gauge at Intercomp through Summit Racing for only $169.95, which sounded reasonable. For more information about ASE, visit the official ASE website at www.ase.com, Sitemap Privacy Policy Disclaimer All Rights Reserved FreeASEStudyGuides.com ©Copyright 2020. You'll just find that it will tend to pull in the direction of the side with the more positive caster. Using the center caster adjustment knob underneath the gauge, zero the caster reading. A good muscle car starting point is 1/2 degree negative. 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Adjust just the upper control arm attaches to the vertical centerline of the ground you are adjust., so setting toe is critical to handling and tire life a corner with minimal effect on driving! Turn-Out figure is popular because the more positive caster to make the track! Adjust all 4 bars to get the appropriate setting produce the most way! To keep an eye on tool to upgrade your toolbox do n't have roll...