jeff spahn

I have spent about 40 minutes reading everything I could find in search today regarding trammlining and my apparent toe-in condition.

My tires are feathering on the outer edge, which from my reading tells me I have a toe-in issue from my most recent alignment.

My ride height is a tiny bit lower than stock in the front. I have bits of wire that are cut to front and rear ideal heights from WSM.

Car trammlines like crazy. I can't yet get my head around the values/settings to eliminate the trammlining. Take an engine apart and reassemble, no problem. Do geometry, I am right now at a loss. I can do it with my eyes with my shotgun to hit a pheasant all day long. Figure it out on paper, forget about it without a refresher course.

So my question is, how does toe-in relate to trammlining. I am running factory spec sizes for the 16" tires (found some 45 sidewall tires!). This thing hunts worse than a hound looking for a fox.

Any help getting me to understand the relationship would be appreciated. Once I get it in my head I want to do my alignments at home. The DIY treads were helpful in their explanation of the parts needed but my eyes began to gloss over reading the initial setup.

SeanR

No answer to your question, but how are the inner tie rod ends?

Leon Speed

No answer to your question either, but the basis for eliminating tramlining is making sure there is no play in the suspension and steering. More specifically: upper A-arms rubber, lower arm rubber, upper and lower ball joints, tie rods and steering rack bushings.

WallyP

OK - Imagine that you are looking down on your front wheels from above as you drive.

You have excessive toe-in.

Each wheel is trying to steer the car - the left wheel is trying to turn right, the right wheel is trying to turn left. As long as you are on a smooth, level surface, the pressures are balanced, and the car goes straight, with no tramlining.

As soon as you hit a slight irregularity in the surface, one wheel gets a little more load. This increases its traction, and it pushes the nose slightly in that direction. The slight turn loads that wheel a little more, since it is the outside wheel, which increases the loading which increases the push which increases the loading which...

Jim M.

Jeff, Use 2 strings to check your toe in. Use any four convenient objects to securely hold two strings that run beside the car, at about wheel center height and an inch or 2 from them, and extending a foot or more beyond the ends of the car. Measure the distance between the strings in front of and behind the car, and make these equal. Make the distances between each rear wheel center and its string equal. Make the distance between each front wheel center and its string equal. Check to make sure the distance between the strings is equal in front of and behind the car. Warning, the track is rarely the same front and rear; so don't use just the measurements from the wheel centers to set your string! Measure the distance from the front of each tire to the string and the distance from the back of the tire to the string. Measure from the EXACT same spots on the tires. Do the simple math to get the difference between the front and back measurements on the front tires. Adjust the tie rods on the steering rack to get the tires almost straight ahead, with the smallest amount of toe-in (tires closer together at the front) that you can measure. You will have to roll or drive the car back and forth after each adjustment to take the load of the tires and let them center again.

We did this exact procedure on Paul Champagne car on our way back from SITM a few years back. Worked very well and his replacement tires were still good when he got home.

dr bob

Jeff--

Tramlining canbe caused by several things. If you still have the original 16" wheels on the car, wheel offset isn't an issue. Besides the alignment, did you change anything since the last time the car didn't tramline? If so, what?

Jim's basic toe-in measurement method is pretty simple. You can see from that whether the toe is off from the just-barely toe'd in target. You will need the calculator if you want to figure out how far off it is though.

Did you get a chance to look at the DIY alignment thread? There are a few good details in there, and a link to Earl Gilstrom's excellent tutorial on checking and adjusting alignment using the method Jim describes.

mark kibort

take a flat edge , level, on the side of the tire/rim on both sides and make a magic marker mark on the ground. (against the level hitting the ground, on the front and the rear of the wheel/tire). do both sides. then, measure the distance between the front and rear marks for both sides. Ive been able to detect and even adjust 1/16" out of my toe. usually, 1 turn for micro adjustments on the tie rod, and 2 for maybe close to 1/8". If you trig it out, it works out to about .25 degrees toe. (i.e. 1/18" / 71" INV-TAN on the calculator)
Dr Bob, continues to ridicule this method, but who on the list has had BETTER luck with doing so? no tramlining, and I have crazy offset wheels, AND tire wear with race rubber, is so good, I sometimes wish the tires to cord in some area so I can toss them. they wear perfectly even, for race and street driving.

**** the reason the level and magic marker work so well, is that it is a definitive position of the wheel and tire to the ground. the mark is made against the level, and it doesnt matter about the thickness variance as Dr bob will cry about. I could actually use a spray can of paint if i want! the only dimension you care about is the point at which the paint or magic marker hits the level. measure it at both sides and you get a valid, comparitive dimension. if you are outer edge scrubbing, you have either too little camber and too much toe-in, and could be a combo of both. personally, I would lower the car 10mm or so, especially if you are at stock ride hight. that way, you get a little more camber, and lose some toe in. thats just my first -glance take on it.

jeff spahn

Thanks everyone. I did look at the DIY page on the "read this" area. My eyes got all glossy. I'll print thread here out and take it to my garage and see what I can do.

dr bob

Mark--

Where does the 71" part of your calc come from?

jon928se

When toe is measured as a distance ie 1/16" or 1.5mm say where is 1/16" measured on the wheel/tyre ?

Is it at the perimeter of the tyre, the perimeter of the rim ? or somewhere else esoteric

The reason I ask is my local alignment shop has a Beissbarth 4 wheel alignment rack that brings up the specs and measurements for toe in millimetres but all other measurements in degrees.

928mac

Take it back to the guy that did the alignment, have him recheck it and compare the specs to the first one. Post the print out here
I am betting that your caster is way out.
All of the things in the other post above are great checks but do you want it bang on or do you want to play with it.

Garth S

Did buddy lift your car with air jacks once on the alignment rack to check tierods, ball joints, etc?
If the car was lifted at all after driving onto the rack - and the suspension not recompressed as per the WSM, assuredly the toe is incorrect, and iffy on caster & camber.

dr bob

Unless the car is settled to an abnormally high setting, the toe will always go towards toe-out as the car settles.

Wear on the outside edges could be toe-out, and the erratic steering reinforces that possibility. Still, you won't know until you measure.

Darty behavior can just as easily be from a poor rear toe setting, by the way. Easy to measure once the strings are set up.

jon928se

It's a function of the length of the straightedge he used - I'm guessing something about 50" long - placed against tire with approx 20" sticking out to the rear then with approx 20" sticking out to the front.

Thinking about it it would be better to use a staightedge with a couple of spacers to press against the wheel not the tyre. In fact it doesn't even have to be straight so long as the same part of the edge is always pressed against the wheel or to put it another way so long as the offset between where it touches the wheel and where it touches the ground is constant.

dr bob

Jon--

That's been part of the ongoing discussion about Mark's method. There's no consideration for sidewall swell, bulges, raised writing, etc.

I did my last alignmnent check with a laser fixture instead of the straight-edge, set up to go against the wheel rather than the tire. Marks on the floor 42" fore and aft of the wheel center, shoot both from both wheels, measure with a tape measure. 3/8" to 1/2" difference is perfect toe-in. You can do the same thing with a straight-edge I guess. Laser pointers are cheap.