Wheel Alignment

[DamirGTI 342]

I've been on wheel alignment adjusting because of this :

http://forum.205gtidrivers.com/index.php?showtopic=89547

 

.. and i was wondering : does it have to be same amount of threads visible on both sides of the track rod ends when the alignment is set up properly or not ? cos i can count 12 threads visible on LH track rod , and 3 on RH track rod ?!

 

Pics :

 

LH rod

 

RH rod

 

....

 

Thanks !

Damir

Edited April 23, 2008 by DamirGTI

[base-1 17]

No it certainly does not

[DamirGTI 342]

So is it Ok. adjusted like this ?

 

(i don't have experience with wheel alignment , but in joke book says that there must be same amount of threads visible on both side of track rods , on LH and RH side after adjusting ..)

 

Rgs !

Damir

[welshpug 1,657]

it should be equal on both sides, if its not you have the chance of the tyre hitting the gearbox or the water pipe, and not getting full lock on one side.

 

the geometry will be out by a greater amount the further you turn the wheel.

Edited April 23, 2008 by welshpug

[DamirGTI 342]

Well all seems fine no wheel rubbing on the gearbox nor on the metal water pipe on the other side .. doesn't pull to left or right it drives fine in a straight line , steering wheel is in the center .. ?!

 

Rgs !

Damir

[MerlinGTI 3]

You could rectify that by taking the steering wheel off and moving it a tooth or two, then adjusting the tie rod ends so your geometry is correct again. Without easy (and cheap!) access to a geo machine though I wouldnt bother if it ist rubbing.

 

Some cars the steering wheel will only go on one way (late clio's for example), some have loads of adjustment, some very little etc... I cant remember what the 205 has (I know it has adjustment though from when I did my new rack).

Edited April 23, 2008 by MerlinGTI

[base-1 17]

So is it Ok. adjusted like this ?

 

(i don't have experience with wheel alignment , but in joke book says that there must be same amount of threads visible on both side of track rods , on LH and RH side after adjusting ..)

I do have experience with wheel alignment, on road and race cars, it's absolutely fine. If you ever try and adjust tracking by counting threads, you'll find it doesn't work!

 

it should be equal on both sides, if its not you have the chance of the tyre hitting the gearbox or the water pipe, and not getting full lock on one side.

 

the geometry will be out by a greater amount the further you turn the wheel.

 

Complete and utter bollocks, sorry pal!

Edited April 23, 2008 by base-1

[welshpug 1,657]

go on, explain your argument then!!

[GLPoomobile 958]

I do have experience with wheel alignment, on road and race cars, it's absolutely fine. If you ever try and adjust tracking by counting threads, you'll find it doesn't work!

Complete and utter bollocks, sorry pal!

 

I don't have experience, but this has come up so many times now, and I've heard enough explanations to substantiate that it should be adjusted equally, so to quote WP "go on, explain your argument then!"

 

Hypothetical and simplified example:

 

With identical spec TREs adjusted equally at both sides, tracking set to 0 toe at center, and steering wheel correctly alligned.

 

Spanner monkey then adjusts both TREs but keeps toe setting a 0 at center. The only way to do this would be to wind one TRE in and the other out.

 

Now lets say that the spanner monkey wound one TRE all the way in, and the other the exact same amount out to maintain toe setting. You would now find that the steering rack when wound to it's stop at either end would be turning the wheels further in one direction than the other. So in theory, in an extreme you could ed up with tyre contact as WP says. I'm sure someone will also mention the Ackerman angle/effect business (over my head!). I may not totally understand the physics, but the theory makes sense.

 

So whilst I will agree that counting threads is not an accurate way to adjust TREs, I still believe that having them fairly evenly adjusted is necessary.

[Toddy 7]

I agree with equal lengths.

 

Set non equal lengths the rack will not be central, therefore one side will have less amounts of lock and will require a larger turning circle, and vice versa.

[DamirGTI 342]

I've just checked on my other Ph2 car , and it also has unequal numbers of threads on LH and RH track rod end

 

So who's right then ?

 

Rgs !

Damir

[Ahl 4]

You are both right, it *should* be equal (provided the track rod ends, etc are the same) but as base-1 says, counting the threads is not an accurate way to set them up!

 

You really need a track gauge or some way of measuring the alignment.

I get down to turning the ends (or the track rods more precisely) less than an 8th of a turn to get the track spot on! You cannot judge that on the threads, and it could easily be very far out doing from that.

 

On the other hand, I have set the alignment using a tape measure against the hubs when I was desperate and didn't have the track gauge. I can actually get it pretty much spot on doing this (measuring it properly thereafter).

[DamirGTI 342]

You are both right, it *should* be equal (provided the track rod ends, etc are the same) but as base-1 says, counting the threads is not an accurate way to set them up!

 

You really need a track gauge or some way of measuring the alignment.

I get down to turning the ends (or the track rods more precisely) less than an 8th of a turn to get the track spot on! You cannot judge that on the threads, and it could easily be very far out doing from that.

 

On the other hand, I have set the alignment using a tape measure against the hubs when I was desperate and didn't have the track gauge. I can actually get it pretty much spot on doing this (measuring it properly thereafter).

 

 

Hello !

 

So what should i do then ? do i have to re-adjust that tie rod length or not ?

 

Can you explain a little bit how to do that on DIY basis (if it can be done this way ..)

 

Thanks !

Damir

Edited April 24, 2008 by DamirGTI

[skinner2k3 3]

Having recently fitted a rack with new TRE's everything was obviously "out".

 

I dont know if this is right but from inside the car I turned the steering wheel clockwise until it stopped. I found mine went about 3 3/4 turns from lock to lock. So from one end I went back approx 1 3/4 turns plus a bit to centralise the rack. Then wound the TREs in roughly to set the hubs parrallel by eye.

 

Then with the front wheels off and axel stands under the wishbones as near to the ball joint as possible (so the suspension would sit naturally) I bolted some straight bar to the face of the hubs. I attached a plumb bob to the end of the bar either side of the hub (same distance both times) and marked on the garage floor exactly where they touched and measured the distance front and rear, left to right. My garage floor is nice and level by the way.

 

I measured 1/2 and inch difference so wound one TRE in 1/4" to equal it out. I suppose I should have wound in 1/8" on both sides but I couldnt be arsed!

 

I am ahppy mine is now set at parrell, or at least good enough to drive to a tracking place. Havent checked clearence lock to lock yet so all the above could be bollocks

[Rob_the_Sparky 9]

Hello !

 

So what should i do then ? do i have to re-adjust that tie rod length or not ?

 

Can you explain a little bit how to do that on DIY basis (if it can be done this way ..)

 

Thanks !

Damir

 

Stop worrying about nothing, you say you have no problems - follow the engineering mantra:

 

If it ain't broken then don't fix it

[DamirGTI 342]

Stop worrying about nothing, you say you have no problems - follow the engineering mantra:

 

If it ain't broken then don't fix it

 

Ok !

 

Rgs !

Damir

[eeyore 0]

There should be an equal number of threads showing providing both trackrod ends are the same type. if one is further in than the other it moves the rack out of center, this creates the effect of different length steering arms which also creates bump steer in different directions on each side. you need to make sure the rack is properly centered before setting the tracking and then make sure the front wheels are facing the same way as the rears. Most of the competition cars that i set up arrive with rack out of center and once put right people are surprised at how much better it drives. Its quite an easy problem to sort out and it surprises me that so many people ignore it.

[skinner2k3 3]

So have I done it about right?

 

I guess if I measure the distance from the end of the TR to a point on the wishbone and they are the same on both side it's got to be right??

 

Also whilst on the subject (excuse thread hijack but this may be interesting for some).....would I be right in thinking Toe-in is more stable at speed and tends towards understeer and as you go through parrallel and to degrees of Toe-out the stability decreases and the car will tend to oversteer slightly turning in?

[welshpug 1,657]

So have I done it about right?

 

I guess if I measure the distance from the end of the TR to a point on the wishbone and they are the same on both side it's got to be right??

 

Also whilst on the subject (excuse thread hijack but this may be interesting for some).....would I be right in thinking Toe-in is more stable at speed and tends towards understeer and as you go through parrallel and to degrees of Toe-out the stability decreases and the car will tend to oversteer slightly turning in?

 

Measure from the centre of the TRE (where it bolts to the hub carrier) to the locking nut on the track rod, a more accurate way to check it than counting the threads.

 

Toe in makes it more stable in a straight line at speed at the expense of turn in sharpness, parallel makes turn in sharper, but more nervous in a straight line at speed.

[Tom Fenton 1,541]

There should be an equal number of threads showing providing both trackrod ends are the same type. if one is further in than the other it moves the rack out of center, this creates the effect of different length steering arms which also creates bump steer in different directions on each side. you need to make sure the rack is properly centered before setting the tracking and then make sure the front wheels are facing the same way as the rears. Most of the competition cars that i set up arrive with rack out of center and once put right people are surprised at how much better it drives. Its quite an easy problem to sort out and it surprises me that so many people ignore it.

 

Absolutely agree with this.

On other stuff I work on there is a plug in the rack which can be removed, and then a dowel dropped in which locates into a drilling, and centralises the rack accurately. I don't know of this feature on a 205 rack so the only way to do it that I am aware of is to measure the turns of the wheel and do it that way.

 

If fitting a pair of new track rod ends this is how I do it.

 

Screw both in an equal amount that you think will be somewhere near, then ignoring steering wheel position turn the rack so the wheels are straight and check the tracking, ignore the steering wheel position. Then adjust both track rods an equal amount, either shorten (more toe out) or lengthen (more toe in) BOTH to achieve whatever overall toe you desire. Once you've done this and locked the track rods off, then you can centre the steering wheel up by removing the nut and indexing it round on the splines.

 

If you are adjusting an existing pair then really the easiest thing is to remove them completely, give them a dose of grease to make them easy to adjust now and in future, and then do as above.

[skinner2k3 3]

Measure from the centre of the TRE (where it bolts to the hub carrier) to the locking nut on the track rod, a more accurate way to check it than counting the threads.

 

Toe in makes it more stable in a straight line at speed at the expense of turn in sharpness, parallel makes turn in sharper, but more nervous in a straight line at speed.

 

Thanks, Parrallel it is then. I did have a bit of toe out before and I fully blame my oversteer/lamp post encounter on that, nothing to do with my over enthusiatic application of loud pedal

[jackherer 543]

Absolutely agree with this.

On other stuff I work on there is a plug in the rack which can be removed, and then a dowel dropped in which locates into a drilling, and centralises the rack accurately. I don't know of this feature on a 205 rack so the only way to do it that I am aware of is to measure the turns of the wheel and do it that way.

 

There is definitely no slot for a pin on a 205 unfortunately. I figured all this out for myself a while ago after several tyre fitters failed to get my pug right. I ended up blagging a couple of hours on my local garages ramp with their laser aligner and it took me ages to accurately centralise it. The people at the garage thought I was insane because they would have just set the toe to the book figure and put the steering wheel on 'straight'

 

Once I had got it right I found it cured some nasty bumpsteer as Eeyore describes but it also makes the steering weight load up evenly in both directions, previously it would feel light if you turned left but heavier if you turned right due to the messed up ackermann effect.

[DamirGTI 342]

So is there any dangerous effect regarding stability/control during the driving when the alignment is setted on this basis (tweak the tie rods and reposition the steering wheel as necessary so that it's in center ..) , or is it just the matter of lock to lock turns/feel ?

 

Sorry i don't understand whachya mean by "bumpsteer"

 

Rgs !

Damir

[jackherer 543]

Bumpsteer is when the toe changes as the suspension is compressed. To prevent it the trackrod and wishbone must move through the same arc keeping the toe consistent.

[allanallen 528 2 Cars]

bugger me, I think ive just learnt something