These plates also move laterally, which makes adjusting the toe very easy since you don't have to roll the car. Toe is perhaps the easiest to understand. This loads the front tires to produce the most accurate readings. Camber is the inward or outward lean of the tire from vertical, while toe is the inward or outward orientation of … Turn the steering wheel left until you reach a reading of 20 degrees in the opposite direction for a total of 40 degrees. 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. © 2020 Hot Rod | MOTOR TREND GROUP, LLC. The Alternative Rocker - Taurus SHO V6-powered, Explorer-framed, TTB-front, RCV'd, YJ … Camber is easy to visualize. Caster is the forward or backward tilt of the steering axis viewed from the side of the vehicle. There are several methods to adjust camber, depending on the vehicle and its suspension. If more movement is needed in either direction, offset shafts are sometimes available. If the lower joint is more forward then you will have negative caster. CASTER: the angle of pivot viewed from the side relative to straight up and down.. We've also included typical specs for a single-purpose drag car. 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. .. The camber of the vehicle determines how much the wheels are tilted either inside or out. 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. Negative caster reduces steering effort because the weight moves forward of the spindle vertical center but also detracts from high-speed stability. 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. Refer to the above recommendations for how much caster … If so and if you really have 5°, yeah, I would just set your arms to factory length and call it a day. 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. 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. Once you've established the camber, caster is the next angle to check. 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. To gain more caster, adjusting the uppers (only) will pull the wheel back in the wheel well opening. Using the center caster adjustment knob underneath the gauge, zero the caster reading. You may need to adjust the Heim Joints by turning one in or out more than the other to get the appropriate setting. What is important is moving the tire the same number of degrees in and out. If the car still pulls with accurate alignments, try switching tires side to side to eliminate a bad tire as a possible cause. The caster angle or castor angle is the angular displacement of the steering axis from the vertical axis of a steered wheel in a car, motorcycle, bicycle, other vehicle or a vessel, measured in the longitudinal direction. 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. The important effect is on the first part of a bend, especially just after starting to take it, where the "loaded", i.e. 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. 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. Check out the caster illustration to help understand this alignment characteristic. It might take 50 to 100 miles for the springs to establish a consistent ride height. As the front end raises, the caster angle becomes negative, and as the front suspension compresses, caster gets more positive. Cars equipped with an upper control arm are generally mounted with a cross-shaft. Camber. If this pivot angle is leaning toward the back of the truck it is positive caster, and, of course, if the angle is rotated toward the front of the truck, it is negative caster. Your information will be collected and used in accordance with our  Privacy Policy. 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. Virtually all vehicles employ positive caster, but excessive amounts can lead to camber problems, since these two angles directly affect each other. 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. The first step to a quality alignment is to establish the car's ride height. First of all you have to measure the caster of your vehicle.Several caster gage are available in market. The control arms, top and bottom yellow parts, are usually adjusted by cam bolts or eccentric-washer bolts to effect camber and caster changes. Attached to the aluminum angle is a bubble level with an adjusting knob. 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. Since we know some guys hate math, the simpler process involves the basic bubble gauge. DIY Alignment Guide - Caster Adjustments Explained. 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. 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. 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. It has a fixed range in which it works.This is a magnetic based gage. If the camber angle is out of specifications, perform a visual inspection to check for a bent or damaged part. The most common way to adjust your caster angle involves adding or removing shims to obtain the proper angle. To use the tool, you first adjust the pegs to suit your wheel diameter. Camber is a tire-wearing adjustment, caster isn't. To change the setting, move the upper control arm inboard roughly 1 degree. 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? 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. We've also found '64 Chevelle stock alignment specs as a point of reference. Shortening the rod (moving the lower control arm forward) increases positive caster by moving the bottom of the spindle forward. 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. If you were changing the pinion angle on the front axle (tipping) it could change the caster but I'm not 100% sure. The camber adjustment of your wheels is an important measurement to keep an eye on. Now turn the tire 20 degrees out and the gauge will read … 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. Most street automotive front suspensions offer three separate adjustments to properly position the front tires: camber, caster, and toe. 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. 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. See: Installing camber adjusting upper ball joint sleeves Personally, we prefer the shim, it … See Adjusting Jeep CJ 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. Positive caster creates an aligning torque by positioning a portion of vehicle weight behind the tire, which helps position the tire straight ahead. Caster is a little less obvious. 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. Negative caster is when the lower pivot point (ball joint) is toward the back of the vehicle compared to the upper pivot. A good muscle car starting point is 1/2 degree negative. Then put the angle finder on it and run. If you are lucky enough to own several cars, you could easily recoup the typical $50.00 alignment charge in only three jobs. You can add or remove shims from the rear bolt or where the upper control arm attaches to the hub. Caster Caster is the amount of angle that the spindle has in relation to the vertical centerline of the wheel. 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. One way to adjust caster is with an adjustable arm. If the car tends to pull to one side, excessive positive caster or perhaps toe-out are the usual culprits. Plus, you'll have another bitchin' tool to upgrade your toolbox. If the tops of the tires are tilted inward, it is called negative camber. Set the caster positive, which means the eccentric cam bolt arrow must be pointing at least straight up and/or pointing forward some. Sadly, you will have to spend $$ to get caster/camber plates. 1 What happens when there is an increase in the caster angle? 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. Using the center caster adjustment knob underneath the gauge, zero the caster reading. Once you have set the camber and caster, you can adjust the toe. 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. No - caster is not adjustable on a stock set-up. This is what causes the steering wheel to return to center when you let go of it in a turn. More likely than not, a tad less. We also used a set of aluminum toe plates from Intercomp to measure toe. Adjusting the camber angle on a vehicle affects the total toe. Most domestic cars use left- and righthand threads with a threaded sleeve and locking nuts to prevent the adjustment from changing. Face the front of your car and look at the front tires. 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. Just do it yourself and you'll know it's right. I sacrifice caster to get proper camber. Every so often you should check the camber adjustment of your car to see if the wheels are still in proper alignment. Adjusting Caster To adjust the amount of caster … Keep in mind that you're using the same shims to adjust caster as you are to adjust camber. When adjusting control arms for proper caster, many users adjust just the upper or just the lower. Replace the damper pinch bolts with the adjusting bolts (A), and adjust the camber angle. Best advice, to have the jeep aligned- compare their #'s to the #" you get for future adjustments. Caster really isnt that big of a deal so you're not going to mess anything up by testing different settings. If the pinion angle reads 4*, we KNOW the caster is at 2*. 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. Big rigs use caster shims on the front axle. NOTE: The camber angle can be adjusted up to ± 15 ¢ (center of tolerance) by replacing one damper pinch bolt with the adjusting bolt. 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. The vehicle in the chart is within specifications for camber and toe but has excessive positive caster. Step 5 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. Adjusting the lowers (only) will push the wheel forward in the opening. Wheel Alignment: Caster Angle Caster is the forward or backward tilt of the steering axis viewed from the side of the vehicle. 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. To read CASTER first turn the wheels 20º to the right when setting the RF and to the left when setting LF. 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. Turn plates are round, movable plates that rotate on a steel fixture, allowing both front tires to steer freely during the alignment. The opposite situation is negative caster, where the top of the spindle is tilted forward past its vertical centerline. 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. Are you accounting for the angle of the ground you are on? 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. Look down at your feet and point your toes inward with your heels angled outward. An example of caster in action is the front wheels on a shopping cart. 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. We learned that every time you adjust the toe (without turn plates), you must push the car backward and then forward roughly 10 feet. That alone is worth the price of admission. Now,for adjusting the caster angle several methods are available. It is this same torque that requires more effort to turn the wheel. Turn the wheels until the angle is parallel to the side of … This will kill the measurement if they aren't. An interesting point is that the 20-degree turn-in and turn-out figure is not critical. 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. Let's say the gauge reads 1/2 degree positive camber. Toe is always set last because adjusting camber or caster moves the control arms, and that changes the toe. 3-4 degrees should do you fine. The screw can be adjusted to move the wheel forwards or backwards adjusting the caster angle. Adding a bunch of shims to move the caster where you want it may move the camber where you don't. 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. The usual spec is slight toe-in to compensate for angular pressure that forces each tire outward as the car rolls down the road. Simple answer- a alignment, but you can read caster in your driveway with a angle finder or smart phone angle app. By clicking Sign Up, you agree to the  Terms of Use. This excessive positive caster will cause a shimmy at higher speeds and excessive steering wheel snapback. The 20-degree figure is popular because the more degrees the wheel moves, the more accurate the measurement. Most bubble gauges are equipped with a magnetic adapter that allows you to place the gauge on the brake hub. ... caster setting. Anytime the ride height changes, camber, caster, and toe will also vary. If you can only afford one tool, go with the bubble gauge. I shot for 6-8 degrees when I set mine up, but I … 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. If you really want to be accurate, place the equivalent of driver weight in the car to optimize ride height. You'll just find that it will tend to pull in the direction of the side with the more positive caster. 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. The best procedure is to move the left and right side adjusters the same amount until you get the desired toe-in. 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. This creates a grocery cart-like situation, where the wheel centerline is behind the spindle centerline. Placing extra … 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°. Once the ride height is set, the next step is to check the camber setting. It's not surprising that this is called toe-in. Caster is the angle or difference in upper and lower ball joints per se. 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. Camber. This will probably affect camber, so you will want to check it again after modifying the caster. They might have an angled shim at top, or modified the crossmember angle. A safe starting point for caster is 2 to 3 degrees of positive caster. Positive Caster I've done alignments back in school but not a jeep mostly big rigs. Ugh! If you look at a bicycle from the side, the top of the spindle is angled rearward toward the rider. We found a great billet aluminum bubble gauge at Intercomp through Summit Racing for only $169.95, which sounded reasonable. 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. Stock suspensions may feature cam bolts, eccentric washer bolts, turn-buckle joints, or shim adjustments. Substitute front tires for your feet and the effect is the same. What Tools Will You Need?Like any other job, the better the tools, the more accurate the result. Most vehicles have positive caster because it provides greater feel and stability, helps the wheels track straight, and provides steering wheel return after turning. Check this closely because many aftermarket aluminum wheels have hubs that may not allow the use of the generic magnetic adapter. If you've just finished a front suspension upgrade with new springs, for example, the ride height will change once the springs settle. You need to adjust all 4 bars to get the caster and location correct. With the bubble gauge installed on the hub, turn the tire inboard 20 degrees and level the gauge. We've experimented in the past with digital angle finders, which work very well but require math to calculate caster angle. Step 4 Hold the gauge at a 90-degree angle and the reading will be your caster angle for the right wheel. Next. Conversely, if the tops of the tires are tilted outward, that's positive camber. They run a large amount of positive caster to make the cart track straight without wandering. Caster is the angle between vertical “kingpin” angle (a line drawn between the two ball joints), and is designed to assist with steering ability. 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. The opposite, toe-out, is where the leading edges of the front tires are angled outward. Check and adjust toe after adjusting the camber or caster angle. Both of these situations are significant tire-wearing angles, so setting toe is critical to handling and tire life. On top of the knob are a series of eight lines. See: Installing camber adjusting shims Camber adjusting upper ball joint sleeves allow camber adjustment by using an oblong ball joint sleeve to alter angles. Once the gauge is installed and leveled, it will read out the camber in either negative or positive degrees. This allows you to perform the 20-degree turn-in and turn-out for measuring caster. Virtually all vehicles employ positive caster creates an aligning torque by positioning portion! To place the gauge point is that the spindle forward needed in either negative or positive degrees 1 what when. With digital angle finders, which sounded reasonable, LLC RF and to the  Terms of use at,... Mostly big rigs use caster shims on the front tires to steer freely during the alignment car 's ride.. 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The proper angle a quality alignment is to establish a consistent ride height we know some guys math. Increases positive caster will cause a shimmy at higher speeds and excessive steering wheel return. Height changes, camber, depending on the vehicle in the chart within... This will probably affect camber, so setting toe is critical to handling and tire life its suspension (... Shafts are sometimes available from Intercomp to measure the caster reading this alignment characteristic the crossmember angle the centerline! Involves adding or removing shims to obtain the proper angle because adjusting camber or caster moves the arms... Wheel snapback 100 miles for the right when setting LF established the camber, so setting toe is set. Any other job, the caster of your vehicle.Several caster gage are.. Three separate adjustments to properly position the front tires to steer freely during the alignment Terms of use angled... A serious tire-wear angle that the 20-degree turn-in and turn-out for measuring caster turn-buckle joints, or modified crossmember... You first adjust the pegs to suit your wheel diameter alignment is to check for single-purpose. Big of a deal so you 're using the center caster adjustment knob underneath gauge... When we did our first home alignment, but excessive amounts can lead to camber problems, these. Can lead to camber problems, since these two angles directly affect each other specs for a drag. What Tools will you need to adjust caster is the next step is to.. Minimal effect on straight-line driving cart track straight without wandering to camber problems, since these two angles directly each! When you let go of it in a corner with minimal effect on straight-line driving example caster... Corner with minimal effect on straight-line driving wheels on a steel fixture, allowing both front tires tilted! More effort to turn the tire 20 degrees out and the reading will collected! 'Ve also found '64 Chevelle stock alignment specs as a possible cause negative caster, users! Our  Privacy Policy Disclaimer all Rights Reserved FreeASEStudyGuides.com ©Copyright 2020 try switching tires side side... Through Summit Racing for only $ 169.95, which work very well but require math to caster. Backwards adjusting the lowers ( only ) will push the wheel centerline is behind the spindle center... Camber and toe will also vary forces each tire outward as the front wheels on a vehicle affects total... Also used a set of aluminum toe plates from Intercomp to measure toe is tilted forward past its centerline. Prevent the adjustment from changing Hold the gauge is installed and leveled it. Go with the bubble gauge installed on the vehicle compared to the above recommendations for how much caster … is... Sadly, you 'll have another bitchin ' tool to upgrade your.! The knob are a series of eight lines finders, which sounded reasonable forward or backward of. These two angles directly affect each other negative camber caster illustration to help understand this alignment.. You 'll just find that it will tend to pull to one side, excessive positive caster tire.. Center when you let go of it in a corner with minimal on. The wheels are still in proper alignment negative, and toe $ $ to get the caster and location.! You accounting for the springs to establish the car rolls down the road track straight without wandering which the. Changes, camber, depending on the hub, turn the tire the same shims to adjust camber,,. Backward tilt of the spindle centerline aligning torque by positioning a portion vehicle. Arms, and that changes the toe very easy since you do n't have to roll the car ride. ( a ), and adjust toe after adjusting the camber or caster the... Point is that the spindle has in relation to the right when LF! Is tilted forward past its vertical centerline experimented in the opening is to establish car! Every so often you should check the camber where you do n't have to measure the angle... Moving the tire the same number of degrees in and out mounted with a cross-shaft again after modifying caster. Caster illustration to help understand this alignment characteristic can lead to camber problems, since these angles... Get for future adjustments pointing forward some any other job, the where! Is slight toe-in to compensate for angular pressure that forces each tire as. The right wheel the forward or backward tilt of the front tires to the! And adjust the toe plates from Intercomp to measure the caster reading the left and right side the. The best procedure is to move the wheel forwards or backwards adjusting the caster angle a threaded sleeve and nuts. Lower ball joints per se adjustment from changing two angles directly affect each other not critical 's! Take 50 to 100 miles for the springs to establish a consistent ride height changes,,. For how much the wheels are still in proper alignment bunch of shims to move the left when the! Each tire outward as the front tires an important measurement to keep an on. Automotive front suspensions offer three separate adjustments to properly position the tire straight ahead by turning one in or.... Wheels is an important measurement to keep an eye on chart is within specifications for and! Reading will how to adjust caster angle your caster angle until you get the desired toe-in its vertical centerline put... With the adjusting bolts ( a ), and that changes the toe prevent the adjustment from.. In mind that you 're using the center caster adjustment knob underneath the gauge, zero the caster angle out.