20 replies to this topic

[Grimmy@JHE]

this couldn't be simpler. no need for £500 tracking gauges or paying some monkey to change your track.
track of a car is very important. not only for handling, but for economy.
if your wheels arnt pointing in a straight line then you are constantly scrubbing your Tyre. this not only reduces the Tyre life but costs your more in fuel to rub away your nice new tires.
on the handling front, the toe of the front wheels can change the feeling of the car dramatically. more toe in on the front will help the car turn into corners better but loose speed and get a bit "skity" on long straights.
the joy of doing this yourself is that if you don't like how the car is handling or you have made some grave mistake, you can always set it back to its base settings so you cant go wrong really (unless you go lathering round the roads when you have just changed something...).
im not saying that track is the be all and end all of suspension settings, far from it. but its a good start and for what it costs, its a very cheap good start.

what you need is
two straight bars. i use steel box section.
some visible fishing line - i use pole elastic. the fishermen around here will know what im on about. ill explain why elastic rather than string later.
a steel rule

1. get your bars and weld or put a bolt through each end of the bars. the bars need to be roughly 12-15 inches longer than the width of the mini.
if you have wide arches and wheels then add a bit extra. the bolts need to be the same length apart on the bars. this is crucial so spend a bit of time getting it spot on. try to use small bolts like m5 / m6 this ill keep the elastic / string central on the bolt. say 1 inch box is used, use a 2 inch bolt so there is plenty left sticking out of the bars. this needs to be done at all four ends of the bars.

2. next get the bars and figure out a way of mounting them at the front and the back of the car. they need to be at the same height as the stub axles. i just drilled some some and used cable ties but if you value your paint job i wouldn't recommend drilling holes. the bars need to be solid but be able to move side to side.

3. next get the elastic roughly half the length of the mini and tie a hole in each end. put each loop round the bolts on one side of the car and do the same with the other. the reason i use elastic is it keeps tought when measuring against.

should look a bit like this paint master piece. just a bit more colorful.


4. now you have to square the elastic up to the car. you do this by using a steel rule and measuring from the stub axle to the elastic. you do this on side of the car. then move the bars until the measurement from one side is exactly the same as the other.
if you start with the front one and then go to the back one, make sure the front one is still right. you need to get this bob on.

5. now measure the distance between the front edge on the wheel and the back edge. the difference is your track in mm or inch.

the base settings i use for road mini's is

1/16th or about 2mm toe out on the front.

1/16th or about 2mm toe in on the back.

just to clarify toe in and toe out.


and that's it. any questions or anyone disagrees with anything iv said then please get in touch.

[GraemeC]

Surely to measure the toe angle in linear units you need to specify the the distance away from the stub axle at which to measure? For example if measured at the wheel rim the dimension will need to be different for 10", 12" and 13" wheels.

[megabob]

its not a bad idea, just need 2 large polls, screws and a massive rubber band. will save you a few quid

[dave21478]

The problem with theis method is that very few minis are actually "straight" to within a few mm tolerance. Twisted shells (factory tolerances are pretty big, or badly done repairs) play in subframe mounts, cheap patern subframes etc, it all adds up to making it very difficult to be sure the string is square. The 2 lengths have to be absolutley parallell or any measurements will be false.
This should also be done on a flat level surface with the car sitting with the handbrake off.


An easier method is to use 4 breeze blocks etc. Put 2 on either side of the mini, one infront and one behind the wheel. Loop the string around them at centre of the wheel height, then move the mini back out of the way. Use a tape measure and an assistant to adjust the position of the bricks slightly till the strngs are parrallell, then roll the mini back into place. You can then do the measurements as above.
Also, after each adjustment of a track rod end, the car should be rolled a few meters backwards then forwards to allow the wheels and tyres to shift and the steering to settle, before re-measuring.


The red squares are bricks or other heavy objects and the green is whatever string you use pulled tight between them.


Whilst I agree that DIY tracking is handy, (I do it all myself) unless you are VERY accurat, it will never be as good as any adjustments done properly by a garage with the right equipment. An error of just a couple of mm is enough to alter the tracking adversely. The main problem is that most people wont feel a difference unless its pulling massively to one side, and will only notice a problem once their tyres have worn down enough to show uneven treadwear.

[markaboot]

anyone rate the gunsons trakrite tool?

link

[Grimmy@JHE]

i dont agree with your "breeze block" method. how would you know that the car goes inbetween the breeze blocks square?
the good thing about the bars is that it moves with the car as you rock it back and forth.
obviously the bars have to be set right or there is no point in doing it. im prity sure i mentioned this.
it shouldnt matter if your subframe are twisted or what not. as long as the front wheels are inline with the back ones... if the subframe is twisted then i think that should be a problem rectified before worrying about handling. solid mounts would help but there is no reason why standard mounts wouldnt be fine. if there in good condition then there is nothing wrong with them.
also tyre pressures should be checked before starting. it was late last night.
yes it should be done on flat ground, im sorry i left that out. also rocking it back and forth bit. i guess i was presuming that people would know that. slip angles and all...

i did say that the 2mm was a base for standard mini's. the extra couple of inchs would change the angle yes, but i cant and dont know every measurement for every angle on every wheel. allthough someone might have an answer to this.

if you dont have confidence in what i say or the method then dont do it. i string up porches that are race cars at work and use this method every time and i have no complaints from the race drivers.

[Scruffs]

There's obviously a few ways to tackle this one...I know everyone will have their preferred method, but I do not see why breeze blocks/welded structures etc. are necessary...I just use fishing wire alone. Attached are a couple of pics of when I strung a citroen (yes, it is toeing in a huge amount, the rack was wrong). This car had no problems when it hit the road again, I drive it every day.

One thing I haven't seen mentioned so far is centring the steering wheel? This can be done either with a helper, or on a mini I believe you can drop a 1/4" rod into the passenger side of the steering rack to lock it centrally.

If you have a garage you trust then using fishing line correctly will be just as accurate so long as you take your time. If it is an unknown garage I would rather do it myself with fishing line.

Al

EDIT: I suppose on skinny tracked minis it will be impossible to get the string down the side of the car due to the bodywork with my method. In that case breeze blocks, steel structures etc. may be required, although I have never used this way personally so can't vouch for accuracy...

Attached Files

•  02_Offside_String_Gap.JPG   53.89K   152 downloads
•  03_Offside_Along_String.JPG   34.62K   136 downloads

Edited by Scruffs, 15 October 2008 - 01:11 PM.

[dave21478]

It doesnt matter if the car isnt square between the strings with the breeze block method, its basic mathematics to work out the differences between each side and how much to adjust accordingly.

[Scruffs]

Dave did you mean to draw the string running along the entire length of the car? Otherwise there is no way to relate the front and rear axles together which is the whole point to tracking up the car...If you set your method up as accurately as you can, then all you could do is measure the toe setting on one axle then the other, but the car could still be driving in circles!

If the string ran along the length of the car, then It would seem to me grimmy and dave's ways are fundamentally the same. I think if you can, then the string should be against the tyre as this only requires one measurement per wheel, as opposed to three per wheel in the other method (distance to wheel centre, front gap, rear gap). And Graeme's right, string gap needs to be specified at a certain radius from the wheel centre, I use the widest part of the tyre sidewall.

[r_i_c_h_1]

£500 on tracking guages! You've been looking in the wrong place I'd say. Ive seen second hand dunlop guages sell for as little as £20, accurate tracking with none of the bodge involved!

This is of course overlooking the fact tracking only costs around £18 anyway, bit too much hassle making tracking guages to use once a year if you're lucky.

[icklemini]

I can say- and prove if needs be - that strings around the car (especially a mini), are no-where near accurate as proper 4 wheel alignment gear, as for example, it assumes that your subframes are straight in the car. - Its good as a very basic check.

Essentially what is described above is an attempt to straighten the Thrust angle of the rear in relation to the front, now this is fine if the rear wheels were on a fixed axle, they are however independant, and the result of this can lead to a scenario where one rear wheel is toeing out (so that it is 'straight' in relation to the front wheel), and the other rear wheel is toe-ing in (and also straight with the front wheel) - total toe is still ok at 1/16" in (to use a figure).

To adjust the thrust angle, you need to alter the subframe, not the wheels.

Those that want a professional setup (i class myself as a pro in this respect having worked with various race formulas and road cars for a number of years now. rather than a 'monkey'), will notice a difference. Those that come to me, get a full explanation and shown what is what. = Rather than rumour/gossip!

having one rear wheel toeing out, and the other toeing in, leads to oversteer in one direction, understeer in the other.. and can cause an easy spin if bad enough.

HTH,
Dave

Edited by icklemini, 01 November 2008 - 12:17 PM.

[blue redtop]

why not just pay the £20 and get it done properly. will take about half hour.
better than spending all day trying to do it with string.

Edited by blue redtop, 01 November 2008 - 03:29 PM.

[icklemini]

the £20 kwic-fit brigade will only do the front alignment.. if you are lucky the 4 wheel alignment too...

if you want cambers, castors, rear toe, front toe and alignment doing then you have to go somewhere else and it costs more than £20 quid.

Edited by icklemini, 02 November 2008 - 09:14 AM.

[blue redtop]

even if it does cost more its got to be a lot less hassles than guessing with bits of fishing wire.

just my thoughts.

[icklemini]

totally agree - it will be a lot less hassle and far more accurate