On the front of the E36 (I'm assuming that all E36's use the same steering linkages and whatnot) how many flats in/out must one go to equal a degree? I meant to measure/calculate it today, but forgot. Figured if someone already had this info written down, that'd same me some work.

Thanks

Wow... no responses at all. Does this mean nobody knows this? If so, how on earth do you people setup your cars? Just go with what someone tells you alignment wise and then play with tire pressures and hope for the best? :confused I doubt everyone has the time to string up the car between quick/minor changes.

I poked my head under the car today and got a thread pitch measurement on the tie rods along with eyeballing the length of the steering arm bit on the upright. Thread pitch is ~1.5 and the length was ~13cm. Quick and dirty math with those relatively close numbers gives me ~0.661 deg per turn, so ~0.11 deg per flat.

Anyone care to check/confirm/refute these numbers?

"Real" race cars don't use the stock steering linkage. ;)

"Real" race cars don't use the stock steering linkage. ;)
Fair enough. Though I would think there are plenty of "fake" race cars on this forum too... ;)

Actually, I probably have the answer you are looking for written down somewhere in the race trailer. I just don't have it memorized. If I gave you the answer that's in my head I couldn't guarantee whether it was for a BMW, a Miata, or a Formula Mazda.

$90 for the year long alignment at NTB, take it back as much as I want

=)

I guess for autocrossing the idea of dialing in very specific settings for a course while at the track isn't as relevant..

can you just use one of those stick on level devices to get relative change measurements?

Wow... no responses at all. Does this mean nobody knows this? If so, how on earth do you people setup your cars? Just go with what someone tells you alignment wise and then play with tire pressures and hope for the best? :confused I doubt everyone has the time to string up the car between quick/minor changes.

I poked my head under the car today and got a thread pitch measurement on the tie rods along with eyeballing the length of the steering arm bit on the upright. Thread pitch is ~1.5 and the length was ~13cm. Quick and dirty math with those relatively close numbers gives me ~0.661 deg per turn, so ~0.11 deg per flat.

Anyone care to check/confirm/refute these numbers?

$90 for the year long alignment at NTB, take it back as much as I want


Makes for a long day at a Test and Tune driving back and forth to NTB to realign the car :).

No, I doubt that you'll be making a lot of toe changes at an event, but it's good to know the information if only to know what your toe settings are if you do adjust them from the initial conditions. That way, you can record what the settings were and get back to them if you change springs/struts either at the track or at home. It just makes things faster and easier.

First of all, as you change the tie-rod/end assembly, the change in degrees will not remain consistant with each turn. The the farther you deviate from zero toe, the less angular change you will get with each turn.

For practical purposes, you could always set your car up with zero toe and just count the number of turns to get the handling you want and to return to zero.

Even more practical is to get or make some toe plates.

I have a friend who made his own toe plates from angle iron and some nuts and bolts. With that and a Smart Camber gauge he won a bet at a race some years ago that he could measure the alignment of a car (within a very small margin of error - something like 1/32" toe for example) as well with with his stuff as his buddy with a new portable laser alignment set-up. He won and drank free beer all weekend. You don't have to spend wheelbarrows full of cash or spend hours with string and jack stands or whatever to do a decent alignment.

On the front of the E36 (I'm assuming that all E36's use the same steering linkages and whatnot) how many flats in/out must one go to equal a degree? I meant to measure/calculate it today, but forgot. Figured if someone already had this info written down, that'd same me some work.

Thanks

If you mean how many of the six sides of the tie rod you need to rotate by to get 1 degree at one wheel, it is 1.0714284. roughly.

First of all, as you change the tie-rod/end assembly, the change in degrees will not remain consistant with each turn. The the farther you deviate from zero toe, the less angular change you will get with each turn.

For practical purposes, you could always set your car up with zero toe and just count the number of turns to get the handling you want and to return to zero.

Even more practical is to get or make some toe plates.

I have a friend who made his own toe plates from angle iron and some nuts and bolts. With that and a Smart Camber gauge he won a bet at a race some years ago that he could measure the alignment of a car (within a very small margin of error - something like 1/32" toe for example) as well with with his stuff as his buddy with a new portable laser alignment set-up. He won and drank free beer all weekend. You don't have to spend wheelbarrows full of cash or spend hours with string and jack stands or whatever to do a decent alignment.


Toe plates are perfect for aligning front toe. However, strings allow a 4-wheel alignment and don't take "hours." With practice, you can do the whole car in about 10-15 minutes. I learned this method when I was screwing around with various things on my car and was too cheap to keep paying for alignments.

The trick is to make it as easy as possible. Use "turn plates" so you don't have to keep driving/settling the car and then resetting the strings. These can be two vinyl floor tiles with a squirt or two of grease in between under each wheel. Also, to simplify setting the strings, drill holes through two 1x4 boards at the same time and tie the strings through the holes - that way you know they are parallel.

If you mean how many of the six sides of the tie rod you need to rotate by to get 1 degree at one wheel, it is 1.0714284. roughly.


C'mon Jay, he went thorugh the trouble of making the post and getting a discussion started, the least you could do is give him a number to work with, jebus, you might as well just say 1.07143, he will still not be too precise with this calculations.

I'm thinking tolerance of 1x10-15 or so to properly guage this dimension.

(dork) :lol (dork)

If you mean how many of the six sides of the tie rod you need to rotate by to get 1 degree at one wheel, it is 1.0714284. roughly.

As in ~1.07 flats = 1 degree? Meaning one full turn (6 flats) = ~5.6 degrees?

If you know the thread type, it should be pretty easyif you know the distance of the spindle pivot point to where the steering attaches. You just take the number of threads and for each turn its that part of an inch tomake the triangle between the three points. a Alittl trig action and you got yourself a nice little spreadsheet formula to figure it out for you ;)

If you know the thread type, it should be pretty easyif you know the distance of the spindle pivot point to where the steering attaches. You just take the number of threads and for each turn its that part of an inch tomake the triangle between the three points. a Alittl trig action and you got yourself a nice little spreadsheet formula to figure it out for you ;)

Isn't that what was done above? (minus the spreadsheet bit. we don't need no stinkin spreadsheet. :stickoutt ) Calling it in the 0.1 deg range should be *close enough* given the amount of play in the ball joints and whatnot. 0.11 +/- 0.01 seems a bit rediculous, and I doubt anyone will go past 5 degrees of toe in/out.

at zero toe, the number i come up with per flat is 0.110189
and at 5.3 degrees of toe (8 trips around of the adjusting hex thingy, or 48 flats) the number i come up with per flat is 0.110498

Thats "close enough" in my book. ;) Its just a lowly street car anyway. It can't tell the difference in 0.000309 degrees, can it?

So unless someone says otherwise, I'm sticking with the number 0.11 deg per flat. :D (Hellabad, I still don't follow what you were saying. I don't see how 1.07 flats = 1 degree. :help )

Wow... no responses at all. Does this mean nobody knows this? If so, how on earth do you people setup your cars? Just go with what someone tells you alignment wise and then play with tire pressures and hope for the best? :confused I doubt everyone has the time to string up the car between quick/minor changes.

I poked my head under the car today and got a thread pitch measurement on the tie rods along with eyeballing the length of the steering arm bit on the upright. Thread pitch is ~1.5 and the length was ~13cm. Quick and dirty math with those relatively close numbers gives me ~0.661 deg per turn, so ~0.11 deg per flat.

Anyone care to check/confirm/refute these numbers?

That seems to be around what I calculated as well. Since I'm too lazy to go measure how far the steering rod is from the wheel's center, I'm gonna estimate it's about 6" out from center. So if the thread pitch is 1.5 (i.e. 1.5mm dist. between threads), each full turn will move the rod in/out .059". Change in angle = arcsin(.059/6) * (180/pi) = .56 degrees/turn. I can't imagine wanting to mess with the toe more than .2 deg in either direction. If I'm running 0-toe and I do a quarter turn, I can feel the change big time.

I check alignment using strings. I have centerline marked in several places on the car and have fashioned a setup where I can mount a bar at the front and rear of the car and run strings between them. Takes 10 minutes to setup and about an hour to do an alignment. If the Champ car guys do it this way, why can't I. ;-)