Properly tuning the front steering of a vehicle can sometimes be a real challenge. Improperly tuned front steering can manifest itself in strange problems such as wandering, excessive bump steer, tire wear issues, etc. Resetting the Toe and Camber of your vehicle is paramount if you are doing any type of modifications. Even if you are not doing any modifications to your vehicle, it is still a good idea to check the Toe and Camber settings to ensure the best ride and handling characteristics possible. Proper Toe and Camber settings depend greatly on the specific vehicle and the intended purpose of that vehicle. So please only reference this as a general guide to Toe and Camber. About Toe, and how to measure it: Toe settings greatly impact steering. Toe-out encourages the initiation of a turn, Toe-in discourages turn initiation, while Zero-Toe results in least amount of power loss and tire wear. For most applications, Zero-Toe is desired. So how do you measure for Toe? It's pretty straightforward, but there are a few steps you can take to ensure you get an accurate measurement. You will need a couple of yard sticks (or something similar), a level, some tape, and a tape measure. Move the vehicle to a level surface. Take the yard stick and place it horizontally across the center of the tire, using the hub as center reference. Use the level to ensure the yard stick is horizontally level (see Figure 1). Tape the yard stick on place, and repeat the process for the other front wheel. Now you have accurate reference points to measure from. Figure 1 (click on thumbnails for larger image): Figure 2 - Measuring For Toe: Toe-In: When the front wheels are set so that the leading edges are pointed at one another. Measure the distance from yard stick to yard stick immediately in front of the front tires, and immediately behind the front tires. Toe-in con be confirmed when Distance A is less than Distance B. Toe-Out: When the front wheels are set so the leading edges are pointed away from one another. Measure the distance from yard stick to yard stick immediately in front of the front tires, and immediately behind the front tires. Toe-out can be confirmed when Distance A is greater than Distance B. Zero-Toe: When the front wheels are set so that the leading edges are parallel to one another. Measure the distance from yard stick to yard stick immediately in front of the front tires, and immediately behind the front tires. Zero-Toe can be confirmed when Distance A and Distance B are equal. For the majority of all application, Zero-Toe is the desired setting. To change the Toe settings, most vehicles will require an adjustment to the tie rod length. Exactly what adjustments to make to the tie rod length depends on weather the steering is front or rear. About Camber, and how to measure it: Camber greatly impacts handling as well as steering. Camber is the angle of the wheel relative to vertical, as viewed from the front or the rear of the car. If the wheel leans in towards the chassis, it has Negative-Camber; if it leans away from the car, it has Positive-Camber. To measure camber, you will need a level and an angle finder. Place the level vertically across the center of the tire, using the hub as center reference. Place the angle finder on the level to determine the degree of Camber. Figure 3 - Measuring For Camber: Positive-Camber: When the top of the front wheel leans away from the chassis. The level will show that the tire is vertically out of plumb, and the angle finder will indicate by how many degrees it is out of plumb. Negative-Camber: When the top of the front wheel leans toward the chassis. The level will show that the tire is vertically out of plumb, and the angle finder will indicate by how many degrees it is out of plumb. For most applications, 1-2 degrees of Negative-Camber is desired. Zero-Camber: When the top of the front wheel neither leans toward or away from the chassis. The level will show that the tire is vertically plumb, and the angle finder will indicate zero degrees. Adjusting Camber is a bit more difficult than adjusting Toe. For most early model two wheel drive vehicles, Camber can be set by adjusting the distance between the upper A-arm mount and the frame. The greater this distance, the more Positive-Camber vehicle will have, the less the distance, the greater the Negative-Camber the vehicle will have. See Figure 4. For most vehicles, 1-2 degrees of Negative-Camber is desired. You will need to ensure that both the passenger and driver front wheels have the same Camber settings. Figure 4- Camber Settings. In this image, you will notice that I have 3 Grade 8 washers that act as spacers between the upper A-arm mount and the frame. This results in 2.5 degrees of Negative-Camber when my vehicle is aired up and at normal ride height. U-shaped Camber shims are also available (instead of washers) and allow for small, fine Camber adjustments without the removal of the upper A-arm. Hopefully you found this useful and informative. Cheers.
What about caster? That has more to do with wandering than the others. This is all good information for getting it close before taking it to a good shop. However, Make your camber adjustments before correcting the toe. The toe will change with a camber adjustment.
You're getting better. This has more TECHNICAL merit than your driveshaft angle 101, but I wouldn't want ya' doing an alignment on my car. Ya' missed too many of the basic steps ya' have to take before ya' even think about takin' measurements. AND ..... as was already mentioned, what about caster? How ya' gonna' use those washers and shims on a straight front axle? Sorry if I'm givin' ya' a tough time, but I hate it when tech articles are posted here that are not TECHNICALLY correct.
you missed quite a few points. usually you want just a little toe in, like 1/32-1/16. Also you want slightly more negative camber on the passenger side wheel, about a quarter of a degree, this is to help correct for road crown. adding shims to your a-arm mount doesn't always increase positive camber. if the nuts for the a-arm mount are towards the engine, adding shims will increase negative camber.
All of this should be done, on a fully assembled car as well. Your picture shows a frame with suspension, you'll get close but your suspension is not at rideheight, or the factory height for setting suspension geometry, if you did it without the engine/body you'll be off while driving.
good tips...should get any car to drive straight and true enough to drive right to a shop with a digital laser front end alignment rack...
Putting a level vertically across the tire like he recommends isn't accurate at all. The tires naturally bulge at the bottom from the weight of the car and measuring it this way will indicate more negative camber than is really there. Not even close to being accurate. I worked in a tire store many moons ago and can't remember the alignment guys ever steering Zero Toe either. Most cars are set at slight tow in because of the inherent flex or movement of components that causes them to try and toe out at speed, especially on rear steer set ups. Sorry but this isn't really very good information for a Tech article.
Good info. I still need to do my Chevy. My shop manual says the frame must be perfectly level. Is it that important? Also, my car is going to be down in the ass end a little. Will anything change after setting up my front end with everthing level? Thanks, Todd
In a way he is right. You want as close to zero toe in when you are driving down the road. Howver to achieve this you have to have some toe in when the car is not moving. Hence the 1/32-1/16 that thrasher mentioned, or what ever the manufacture wants.
The manual says that because that's how Chevy intended for the car to go down the road. You need the car setting the way it is going to be driven for alignment purposes or else Caster in particular will be off.
Not really. Okay, maybe kinda. I was reading the one 1959Ford did on repairing cracked cast iron, and read more of his stuff. I liked his techie posts, and noticed a few of 'em had no comments, and way little views, so I bumped 'em so others could see. I figured folks would check out the ones they wanted, and in a few days they'd be buried again... but not until some folks saw 'em. They're really not that bad... ~Jason
The tech. I read said bais ply tires require 1/16 to 1/8 toe in radials 0 to 1/16 toe in tried it on my hotrods works!!!
How many alignment racks do you see in the NASCAR pits?...... Yes, you can do a perfect 4 wheel alignment with a flat floor, Caster/camber gage, tape measure and string. I was lucky enough to work for race teams for 10+ years and learned from some sharp Bubbas. I couldn't afford turn plates, so I used sand on the floor and 2- 1/4" steel plates under the front tires (to both set caster/camber, but toe also). It automatically allowed the suspension to settle . Be sure to roll her back then forward 3'-4' after every toe setting to get an accurate measurement. One trick to get the steering wheel to be straight.....Tie the steering wheel in the straight position. Pull a string from the rear tire to the front along the sidewalls at hubcap height. Set the left front tire "flat" against the string without moving the steering wheel. Do the same to the right front without moving the left or steering wheel. Now measure the toe. Set the toe (1/2 on each front tire) equally. Car should drive straight with hands free and wheel will be set centered.
That works if the front/rear track width is the same. On hot rods it's frequently different. Here you'd have to measure the distance from the string to the tire sidewall (front or rear) and make it the same. Ya' can't do the 1/2 on each side with a straight front axle. Instead you'll have to work with the drag link to center the steering box. I have seen some Bubbas center the str'g wheel by removing it and re-indexing it on the splines . I agree with everything you said, just had to add some. This stuff ain't rocket science.
Also need to note that raising or lowering the rear of the car has the effect of changing the caster setting. Lowering the rear increases caster (the king pins or the imaginary straight line from top to bottom ball joint is tilted further back), raising the rear decreases caster. Also be sure that all tires are inflated to correct pressure before you start doing anything to alignment, as an underinflated or overinflated tire can have the effect of throwing your alignment off.
As noted above: the "string thing" just gives a repeatable starting point. The actual rear axle width, wheel offset does not matter. I just did a buddy's A Roadster last week and he added 1 caveat. He wanted it to turn sharper right than left (The idea was that right turns were ALWAYS sharper than lefts). It only works if your wheel indexes with fine splines and not a keyway...LOL Always measure your rear axle in the frame for primary alignment first. If not, set it first. (Yah)- in the case of the solid front axle, I set the Steering wheel straight first (centering the steering box). String the left front tire to where the string touches both sidewalls at the hub height evenly. Set it by drag link. (rear axle was narrower, so tire was toed out) Stringed the right tire. Set it with tie rod this time. Measured toe. Was 1-1/4" difference (5/8" toe out). Set the left front tire 3/8" more inward with drag link. Reset the right tire with the string, then set it 3/8" more inward. Roll car back and forth 3'-4'(ending on a forward roll). Remeasure toe. (Hopefully) you are at 1/8" toe in. This has worked for me for the past 45+ years or so. It IS quite easy after you do it once. MIZ
That raises a question of how a steering wheel can get out of center in the first place...most have never been removed.
Somewhere in the chassis, not always the front. If a wheel is "curbed", something gives, even a loose rear spring can contribute, but if you make any adjustment on 'toe" only, that will move the wheel off center, so if an adujstment is made on one tie rod end, half of that must be made up on the other one the other direction to keep the steering wheel centered.
Caster is the difference between 2 camber readings - usually 20 degrees left of center and 20 degrees right of center. Much easier and more accurate when done on degree plates. Traditionally camber was set slightly POSITIVE - not negative - to allow for road crown. I was a trainer for John Bean 30 years ago. Haven't paid much attention to specs on late model stuff, maybe negative camber is common now - used to be mostly for circle track setups.
Got no interest in a pissing contest but I just looked back through alignment specs I had handy for 1957 thru 1967 Ford - GM - Mopar - Rambler - all are from Nil (0) to as much as 1 degree positive camber - the only spec that ran negative is Corvette rear axle. Also all list Toe IN - none have Toe OUT.
He's talking about race cars with splined QD's on the steering wheels. I also think he's making a joke. In other news, I don't think I'll be having the OP align my auto any time in the near future.
Gosh for a technical article this is rather lacking. No mention at all of king pin inclination. No mention at all of scrub radius. And caster is pretty important, but was left out too, as others have already noted.
http://en.wikipedia.org/wiki/Camber_angle http://findarticles.com/p/articles/mi_qa3828/is_200206/ai_n9092098 Negative camber resists the tendency of the tire to slip sideways during cornering. It also can increase steering effort. Most cars and light trucks are designed with positive camber, but many race cars and some high-performance street vehicles have negative camber. http://www.patentstorm.us/patents/6786260/claims.html Facts aren't reason for pissing contest, so relax. I must be older than you, your reference '57 through '67, is a mere snapshot of automobile history. Further, (OEM for normal driving) is also only a snapshot. We're on a hot rod/custom/etc/etc/etc forum here. On the circle track we ran diff camber on each wheel. On the salt it varies with the experiment/opinion/R&D of each individual. On my '29 custom I run nil. On my '29 Hot Rod Nash I run Neg. Fact is a large percentage of builders don't even know what 'camber' is, let alone check it. But to get the (rumor) started that all shold be nil or pos is off the mark
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