I have come up with a way to inexpensively and roughly aline the wheels (camber and toe in) on most vehicles. Checking Caster angle is limited but can somewhat be addressed. Since my Fiero is my everyday driver I will supply the specs. and use it for the example.
After a r&r of the cradle I wanted to see how close I could get the alinement using some of these proceedures and then have it alined by a local computerized alinement shop. Then, I was going to use their computerized read out to compare what I had done. To my surprise they would not let me have a copy of the printout even after I offered to buy a copy. However, they did let me read it in their shop and as they said, the toe in was the only thing they had adjusted. I come up with the complete proceedure after being charged for that alinement and it made my car drive worse than when I took it in.
After doing the alinement myself I drove it yesterday and this morning and its seems to be tracking and now the steering wheel is straight in a tangent road. I have made the speedometer bounce off 0 from the back side with a sure feeling of control.
First Off! I jack up each tire slightly with the suspension squated as if it were still sitting on the tire and check for any loose or worn components then grease and check again. Replace components if nessasary first. I do all adjustments on a relatively flat and level concrete floor in my shop.
After this, I start with the camber adjustment for each tire. No tool! You can make them all. All the tools I make are made from:
A string connected to a magic marker (self marking plumb bob), drywall screws, 2x4 board, stiff wire (coat hanger will work), a fishing weight, and a piece of ruler spaced from the board with 1/4 inch nuts. This is used to make a pendulum.
Total cost for all tools made is less than $20 from my local hardware store.
Find a place that is perpendicular to level in order to calibrate the pendulum.
The drywall screws are adjusted for a known reference for straight up and down. Make sure the weighted wire has room to move without resistance between the 2x4 and the piece of ruler that is offset from the board with 1/4 inch nuts. This will ensure a good reading without much variance in how the pendulum is held.
As you should be able to see (sorry for the quality of the photos) the dry wall screws on the side should be spaced to ride on the flat edge of whatever size rim you have.
Approxiamately 1/8 inch movement of the pendulum from center should equal 1 degree of camber for a 14 inch rim.
Formula used for camber: 15(pendulum lenght)x pie/360 = 1 degree
[This message has been edited by Butter (edited 01-14-2002).]
Once the camber is adjusted for each tire then the toe in can be adjusted. I made 3 tools for this adjustment and calibration. Let me first explain the making of the Big Tool and calibration of it.
This is just 2x4's with the board ends being cut to center the rim with the horizontal board. I have marked the wheel base of the car (93.5 inches on my 84) and on one end put those long drywall screws in the side to catch on the rim edge. I clamped a piece of square stock steel to the table in order to give me a parallel line on each side to calibrate from.
I made a marking plumb bob from a magic marker by drilling a hole in the cap end and pulling a string threw it with a knot on the end. I put a short drywall screw next to the wheel base centers marks in order to drape the plumb bob string over for a more accurate and consistant reading.
I put both screws touching the square stock then I use the plumb bob to make a mark on the floor at the wheel base centers. The idea is to make the toe in tool parallel at the reading points.
Flip the 2x4 over and mark the floor at the wheel base centers from the other side. Adjust the screws so that you get the same reading on the floor between the wheel base centers. Once this reading is the same you will have made parallel lines between the edge of rim points and wheel base center points. This tool is now calibrated.
[This message has been edited by Butter (edited 01-14-2002).]
Now there is some info needed from the width of the front and rear wheelbases in order to know the difference for calculations of a parallel line from front to back.
[img] This is the tool I used for getting the differences of width. Its just a block of 2x4 with a screw in the side for drawing the plumb bob string across similar to the above method metioned. I dot the floor with the marker on all 4 tires and measure across from one side to the other. There was approximately 1 inch difference from the front width to the rear width on my car. This measurement divided by 2 will give the offset that must be applied in order to maintain a parallel line from front to rear (front being shorter, add offset to front, subtract offset to rear).
Let me explain. I adjusted the front end first with the steering wheel in the center position by putting the toe in tool with the screws touching both edges of the front rim and measuring from the edge of the 2x4 to the center of the wheel. This is the offset of the toe in tool from the side of the front rim. Minus 1/2 inch (difference from front to back) for a parallel distance from the center of the rear rim then add the toe in degrees distance. OR The front was 1.5 inches offset minus .5 inch for the parallel distance plus .25 for a positive .15 degree toe in equals 1.25 inches from the edge of the 2x4 to the center of the rear wheel for proper toe in, in the front per side.
Once I find the correct distance needed in the rear I set the toe in tool at that position and adjust the front toe in till the heads of both drywall screws touch the edge of the front rim. Lock the adjustment nut in and check to make sure the steering wheel is still straight and the drywall screws are still touching both sides of the rim. Adjusted. Repeat for the other side.
Then I roll the car back a few feet then foward bouncing the shocks a little and then letting it rest from a forward motion and check again. If it checks it will be close enough not to wear tires and drive correctly with the steering wheel straight ahead.
I then adjust the rear toe in remembering that the offset for parallel must be added and the offset for the positve .15 degrees should be subtracted. My car has Fiero rims with the proper offset rims in the rear and Sunbird type rims in the front. The offset for the rear rims when both drywall screws are touching was 2 inches. OR The rear was 2 inches offset plus .5 inch for the parallel distance minus .25 for a positive rear toe in equals 2.25 inches from the edge of the 2x4 to the center of the front wheel per side.
Then I roll the car back a few feet then foward bouncing the shocks a little and then letting it rest from a forward motion and check again. If it checks it will be close enough not to wear tires and drive correctly.
I choose to do the toe in the front end first cause the rear wheels were recently adjusted and I checked to see they were still within tolerence.
Formula used for toe: 93.5(wheelbase)x 2 x pie/360 = 1 degree
Caster is another issue with limited homemade tools. I only checked to see that when I turn the tires equal distances left and right (measuring from the center of the rear wheel the same distance when tire is turned till toe in tool just misses the fender in the front) that the camber tool indicates the same amount of change turn left as right.
[This message has been edited by Butter (edited 01-14-2002).]
Here is what the Pontiac GM Fiero service manual says on the subject if I can get it to post.
Folks I mainly started doing this as a way to r&r the cradle and get the rear wheels alined well enough to test it without harming the rear tires till I could have a true alinement shop do my car up proper. But due to inadequate technicians in this area I felt the need to do it well enough to check those idiots that would like to say they are alinement technicians.
This proceedure can get you by but I strongly suggest finding a good alinement shop.
[This message has been edited by Butter (edited 01-14-2002).]
i brought mine to firestone a few years back. They offer lifetime alignments. They did give me a printout and other info about the alignment.
When i replace all the tierods, bushings etc.. on my fiero. Im gonna use those alignment tools seen in car catalogs and align my car and see how close i can get, before i bring in my car.
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12:01 PM
thomas_l Member
Posts: 1197 From: Alpharetta, GA, US Registered: Apr 2001
Alignments seem sorta mysterious but once you understand the angles there's not much to it.
The imporant thing is setting things up in the right order:
1. Rear camber 2. Rear toe 3. Front caster 4. Front camber 5. Front toe
If you do get (or build) the tools to do this, make sure you get some turntables or at least some wheel dollies to allow the tires to "slip" while you make changes on a loaded suspension.
Those tools are great. The only thing I would question would be the long board . Long 2X4's aren't exactly known for being perfectly straight, much less staying straight. What if you built some sort of platform for the ends and used string lines for the length?
That particular item is why I haven't jumped into home alignments myself. I know I can do a good job on caster, camber, and toe. It's the relation front to back (i.e. dogtrack if it's off) and not getting things "square" enough with homemade tools.
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02:52 PM
rogergarrison Member
Posts: 49601 From: A Western Caribbean Island/ Columbus, Ohio Registered: Apr 99
The way I do toe adjustment is support the car at A arms so springs stay loaded but tires off the ground. Use a can of aluminum spray paint and spray the center of tread while you spin the tire. Makes a complete circle. take a broom handle and put a nail thru one end crossways. stick another nail thru a small piece of scrap wood and use a hose clamp to hold it to the other end of broomstick. Now take an awl or nail and draw a line in the paint mark all the way around the tire. Then use the nails in the broomstick and set them to line up with both sides tire mark towards the front of wheel, then with the hose clamp tite, move the broomstick to the rear with the nail on one side on the mark and look at other tire to see how far the nail is on that side from what it was in front......thats ur tow. Sounds more complicated than it is, but only takes 5 or 10 mins to set it.
Yall please understand I offer this as the best way I have found with limited tools to get car, truck and/or (mainly) dune buggy to drive its best without going to a good alinement shop.
It definately beats a bad alinement shop.
------------------
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05:33 PM
artherd Member
Posts: 4159 From: Petaluma, CA. USA Registered: Apr 2001
I simply used a tape measure, and quite a bit of math :P)
Toe is duck soup to set, almost too easy. camber is a little harder, but easy enough.
Caster is the PITA. Trial and error about five times untill the wheel no longer 'pulled' to either side.
Then I drove it *50miles* to the really good tuner/alignment shop who knew what they were really doing.
Had them align it to my specs (similar to mfg specs, only much less tollerance.)
Go to a place that aligns better german/italian cars, and your alignment will be quite good !
Best! Ben.
------------------ Ben Cannon 88 Formula, T-top, Metalic Red. "Every Man Dies, not every man really Lives" 88 Formula, Northstar, Silver, In-Progreess. -Mel Gibson, "Braveheart"
I agree camber and toe are ez. Ive very rarely had caster set rite on any car from any shop. I dont think anyone test drives car after wards anymore. I alway had to make corrections to make it perfect at home anyway. Trial & error is the only good way to get caster right. I just did the Corvette recently myself, much better. Fieros are the hardest Ive ever run across to get right.Old Mopar and Mercedes had the best setup. the upper or lower a arm mounting bolts were attached to eccentric washer and sat in a pocket. All you had to do was loosen lock nut and turn the bolt to move in or out to change caster and camber. Lots more accurate than normal GM shims or Fords sliding bracket.
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06:52 PM
Fierowrecker Member
Posts: 1858 From: Lowell, MI. USA Registered: Mar 2001
Alignment shops are not precise, most of the time... Definately not as precise! Mechanical tools were in use way before lasers and such started to be used, and depending on how much care is taken, they can do as good a job as the new stuff... Determining the centerline of your car is the best start to a good alignment, and a tape measure can do half the job... I like your plumb bob!
------------------ crash... The Fierowrecker
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06:58 PM
DKOV Member
Posts: 1564 From: Portland, OR, USA Registered: Mar 2001
Originally posted by thomas_l: Those tools are great. The only thing I would question would be the long board . Long 2X4's aren't exactly known for being perfectly straight, much less staying straight. What if you built some sort of platform for the ends and used string lines for the length?
Yea I know 2x4's ain't scraight. That is the reason you must calibrate it. The object is to have two parallel lines between the heads of the drywall screws and the wheel base points from where you are measuring.
Originally posted by Fierowrecker: Determining the centerline of your car is the best start to a good alignment, and a tape measure can do half the job... I like your plumb bob!
I agree. That's what the divided by 2 in the formula does.
Originally posted by Butter: I would like a good answer on that question. If anyone has knowledge of some good setups feel free to post em'.
there is no 'optimal' set up. Everyones driving style is different. What is great for me would be total crap to someone else. I like a car neutral - a little loose for fast driving. That means going into a corner the front wheels do steer it in and steering input together with throttle keep it in line.I can take a car that tends to try and spin out from the back slightly, you can control it with steering, allows you to keep engine up on power curve. (ie Dale E liked loose car, in racing famous saying is loose racecar is fast racecar) Disclaimer-dont recommend driving like your on a race track.... ..)
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08:39 PM
Blacktree Member
Posts: 20770 From: Central Florida Registered: Dec 2001
First of all, I have to say that Butter's article on "home alignment" is very good.
Second of all, now that we know how to set our own alignment, we need to know how to set it to get the handling characteristics we want. We can start by finding the settings necessary for completely neutral handling. We can use this as a baseline of sorts. Then we can modify the neutral settings to achieve appropriate amount of understeer/oversteer that we want.
So, what is the best setting for neutral handling?
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10:12 PM
rogergarrison Member
Posts: 49601 From: A Western Caribbean Island/ Columbus, Ohio Registered: Apr 99
again, no one thing. everything affects the handling. tire size, air pressure, driver weight, just to name a few. Youd have to trial and error for a day to get the handle on the right setup to make your car neutral. Thats why you see racer adjusting on their cars for hours and hours before a race , even during it. Youd have to start with OEM specs for a baseline. Prob have to go to no toe in, increase camber to bite into corners more, increase caster for more positive centering. Of course all that will affect tire wear also. Have to search for happy medium on street car. On our oval race car, we had tons of caster on left front so it would turn into the corner on its own, had to hold it hard straight to go straight.
Originally posted by rogergarrison: again, no one thing. everything affects the handling. tire size, air pressure, driver weight, just to name a few. Youd have to trial and error for a day to get the handle on the right setup to make your car neutral. Thats why you see racer adjusting on their cars for hours and hours before a race , even during it. Youd have to start with OEM specs for a baseline. Prob have to go to no toe in, increase camber to bite into corners more, increase caster for more positive centering. Of course all that will affect tire wear also. Have to search for happy medium on street car. On our oval race car, we had tons of caster on left front so it would turn into the corner on its own, had to hold it hard straight to go straight.
I must agree with all you say there. I've set my car up and took note as to my drivin' habits versis the wear on the tires and noted I needed to adjust the camber for a more even wear in the rear (more negative camber). I also noticed that the brand and rating of tire effects this as well. The V8 helps with the quick wear on the rear tires but I try never to leave a black mark.
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10:19 AM
PFF
System Bot
Formula88 Member
Posts: 53788 From: Raleigh NC Registered: Jan 2001
One thing I found interesting is we're supposed to have REAR Toe-IN on our cars? (well, mine's an 88, so at least for them). That seems odd, and designed to chew up tires. I'd think you'd want the rear to be as close to parallel as possible.
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10:24 AM
SteveJ Member
Posts: 805 From: Orchard Park, NY Registered: Feb 2001
usually cars are set to have a small degree of toe in. thats setting still. when it moving forward, things like rolling resistance will counteract that, so in driving the toe in normally is non existent. Im sure they call for rear toe on Fieros and similar cars because of the rear wheels under torque will make them parallel driving. Thats one thing that is adjustable on independent rear suspensions. Old style solid rear axle assembly didnt require toe- in because they always ran parallel under any conditions.
Originally posted by SteveJ: . . .and on cars with struts and a good alignment use of the camber gauge should return the car to a good alignment after strut replacement.
Too much room for error. It might be close but I believe the toe should be adjusted after the camber or caster adjustment.
[This message has been edited by Butter (edited 01-16-2002).]
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12:55 PM
ToddAsh Member
Posts: 328 From: Springfield,Pa. Registered: Nov 2000
Originally posted by Butter: [QUOTE]Originally posted by SteveJ: [b]. . .and on cars with struts and a good alignment use of the camber gauge should return the car to a good alignment after strut replacement Too much room for error. It might be close but I believe the toe should be adjusted after the camber or caster adjustment..
Well I'm going to go with it. On previous strut replacements I have used a small torpedo level, the kind with the magnet in the base, to establish vertical. I have been looking for better. Stands to reason that if the toe is correct before the strut job and the camber is returned to the previous setting after the strut replacement then checking the toe after the strut is in place will tell you if you are right on. ( and if so no trip to the alignment shop where the monkies will just muck it up.)You gotta remember there is no caster adjustment on many of the strut suspensions.
[This message has been edited by SteveJ (edited 01-16-2002).]
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08:00 PM
Jan 21st, 2002
ltlfrari Member
Posts: 5356 From: Wake Forest,NC,USA Registered: Jan 2002
Everything you want to know about suspension in a very readable form. Bit of maths but not too heavy. Plent of diagrams for the mathematically dim (me !!). It's an older book (1981 I think from the preface) but the laws of physics don't change much.
Approxiamately 1/8 inch movement of the pendulum from center should equal 1 degree of camber for a 14 inch rim.
Formula used for camber: 15(pendulum lenght)x pie/360 = 1 degree
No matter how I cut it, with a 15 inch pendulum I get 1/4 inch of movement = 1 degree. Formula used: Circumferance of circle = 2pi*r (r=radius of circle=15 inch) which gives 94.28 inches. 1 degree of arc = circumference/360 = 94.28/360 = 0.261 = damd close to a 1/4 inch.
One of us is wrong, bet it's me
Maybe someone can confirm one way or the other what the movement would be as I'm planning to use something like this to set my own camber. Just want to make sure I get the numbers right !!
For a 15" radius circle there's a negligible difference in the arc and straight line distance for 1 degree. You're probably using a straight ruler to measure it anyway.
: dusting off Trig brain cells : Tan = Opp/Adj Opp = Tan(of 1 deg)*Adj Opp = .017455... * 15 Opp = .261826...
Also, the circumference of a circle is Pi*D (or 2*PI*R), so I get .2617994...
Looks like .262 either way to me.
Butter, Great idea and explanation! I will be using it sometime in the next few months. I also believe a fairly accurate caster could be measured with these same tools, it's just going to take some 'cypherin' (and maybe an Autocad layout) to figure out what angle on the gauge equals what caster at a given turn of the front wheels. I'll post if I figure anything out.
[This message has been edited by DRH (edited 01-24-2002).]
Originally posted by ltlfrari: Earlier on in the thread you posted :
No matter how I cut it, with a 15 inch pendulum I get 1/4 inch of movement = 1 degree. Formula used: Circumferance of circle = 2pi*r (r=radius of circle=15 inch) which gives 94.28 inches. 1 degree of arc = circumference/360 = 94.28/360 = 0.261 = damd close to a 1/4 inch.
One of us is wrong, bet it's me
Maybe someone can confirm one way or the other what the movement would be as I'm planning to use something like this to set my own camber. Just want to make sure I get the numbers right !!
Dave as I ciphered this I was a wonderin' bout that stuff and here's how I figured it. I was workin' with a 14" rim and a 15" pendulum, the 15" pendulum would read as the diameter since it was the difference from the top to the bottom and the pivit point was in the middle.
(15*3.14)/360=.131=approx. 1/8" or just for simplicity .125" (close as could be read, huh)
For a 15" radius circle there's a negligible difference in the arc and straight line distance for 1 degree. You're probably using a straight ruler to measure it anyway.
: dusting off Trig brain cells : Tan = Opp/Adj Opp = Tan(of 1 deg)*Adj Opp = .017455... * 15 Opp = .261826...
Correct mathmatics but, would you use 7.5 as the correct measurement for the adjacent side since the pivot point is measured from the middle (as shown in the service manual). Anyway I appreciate that some other folks took notice of a question I had pondered. Also if I am wrong, which I may be, it will make reading the pendulum more accurate.
Think of it this way, a 15" wheel rolled 1 degree moves 15*pie/360=.130899693 inches around the tire forward. If a pendulum was used to measure this, the bottom gives up .130899693 and the top moves forward that much. Since the arc distance is negligible and the pendulum is only swinging from the top, it moves .130899693 inches from its previous position. Would this not make .130899693 the measured distance for 1 degree?
Can anyone else confirm the proper reading for 1 degree on the pendulum guage?
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12:12 PM
DRH Member
Posts: 2683 From: Onalaska, WI, USA Registered: Dec 1999
I'm not sure how to explain this but the relevant length is the length of the pendulum. We are calibrating the gauge itself, once calibrated it can measure the angle from vertical of any surface it's placed against. The spec for camber is an angle, that angle will remain the same whether measured from the center line of the axle or across the whole rim.
Probably as clear as mud now...
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02:02 PM
ltlfrari Member
Posts: 5356 From: Wake Forest,NC,USA Registered: Jan 2002
As DRH says, the relevant length is the length of the pendulum. You are measuring the arc moved by the end of the pendulum, relative to it's pivot point, to get your measurement for 1 degree. You are simply using points on the wheel rim to set the angle of the back of the pendulum, relative to the verticle as indicated by the pendulum itself.
------------------ Dave E http://www.ltlfrari.com
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06:42 PM
ltlfrari Member
Posts: 5356 From: Wake Forest,NC,USA Registered: Jan 2002
I useful rule of thumb for small angles is what is know as the one in sixty rule (comes from aviation circles). Basically it says that if you are one mile off course after flying 60 miles your course error is one degree. Reduce that to inches and 1 degree = 1 inch in 60 inches (unless you want a #$%^&* big pendulum )
Divide by 4 and you get a quarter inch in 15.
------------------ Dave E http://www.ltlfrari.com
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06:48 PM
LoW_KeY Member
Posts: 8081 From: Hastings, MI Registered: Oct 2001
We are just talking about setting the camber here. He used a pendulum to determine the camber of the wheels and had calculated that on a 15 inch pendulum, 1/8 of an inch of movement at the end of the pendulum corresponded to 1 degree of camber. However thinking about it, it would seem that the correct amount of movement is 1/4 inch.
[img]
. Long 2X4's aren't exactly known for being perfectly straight, much less staying straight. What if you built some sort of platform for the ends and used string lines for the length?
wore down that fast.. 
