# Tracking vs Geometry



## Pezza4u (Jun 7, 2007)

I wrote this for another forum I'm on but I see alot of threads on here about the subject so thought I'd share it 

*Tracking vs Geometry - An explanation*

There seems to be some confusion as to whether tracking is a good thing or not when it comes to having your car alignment checked. The short answer is no, tracking does not provide any benefits and can actually make the car handle worse or increase tyre wear compared to before. The following will explain why tracking does not work and geometry does.

Tracking is where the front wheels are checked against each other using a laser and then moved until the beam is a mirror of itself on the opposite wheel. However, you need to ask yourself this question, what are the wheels actually being aligned to? The answer is not each other, in fact they are not being aligned to anything using tracking…you will find out shortly what they need aligning to.

The gauges may show the wheels as being out of alignment; however, what they do not show is which one(s) will need adjusting. Therefore the work is done blind, so you could end up with front wheels looking like the following // \\ and even if they do look like this | | there is no way of knowing what the actual angles measure. You can guarantee the wheels will not be accurately aligned because as stated previously they have not been aligned to anything. So to answer the question; what do the wheels align to? The answer is the rear thrust angle; which is the centre point of the vehicles chassis and should always be as close to zero degrees as possible. There is an imaginary line joining both the front and rear wheels together and then a line joining these down the centre. Where the centre line meets the line joining the rear wheels this is the thrust angle and it shows where all four wheels sit in relation to each other.









When a vehicle is measured on a geometry machine each wheel can be independently aligned to the thrust angle with the help of viewing the angles on a computer screen. This is done via separate panels being positioned on each wheel, which are then linked to the computer via lasers. It does not matter if the car only has adjustable front/rear toe, camber, caster or all three. If the rear suspension is adjustable in some form, then a geometry is a must, nothing else will suffice.

If the rear is not adjustable or there are no complaints regarding handling and tyre wear on an adjustable rear, then a four wheel alignment can be done as an absolute minimum, although risky. This is where the front wheels are aligned to the rear regardless of what angles they are currently set to. If the rear wheels are not aligned correctly, whether it is fixed or adjustable suspension, the front wheels will not be accurate. This is the beauty of a geometry, all angles can be measured regardless of what is adjustable or not so this will show any abnormalities such as a bent suspension component or the cause of uneven tyre wear, such as too much negative camber from a broken coil or worn bushes.

The image below shows an example of the rear wheels not being aligned at the correct angles. If this was a four wheel alignment the front wheels would be measured against the rear. Therefore, they would be incorrectly aligned to the grey line rather than the black. This would cause the vehicle to pull as it would use the grey line as its centre and also cause uneven tyre wear. So if the rear had a bent suspension component or the angles are wrong to start with, this would compromise the thrust angle, therefore, the front wheels would be aligned incorrectly.









A geometry check should be carried out whenever the suspension has had work done. It does not matter whether you take the whole suspension out or just change a track rod end. Just undoing a few bolts can change your cars geometry, handling and tyre wear.

Yes a geometry will cost more than tracking and not much more than four wheel alignment. However, in the long run it will be cheaper than having to keep getting the tracking redone because the car does not 'feel right' afterwards, plus there is also the cost of replacing unevenly worn tyres. Unfortunately the majority of the public and industry are uneducated about the realms of chassis alignment and many garages simply can't afford to invest in state of the art equipment, therefore they stick to the tracking method!

If a job is worth doing it is worth doing once and correctly. Hopefully this has helped you understand the differences between tracking and geometry.

For any alignment issues you may have wheels in motion (WIM) has a great forum that can help - wheels-inmotion.co.uk


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## theshrew (May 21, 2008)

I have to agree with what you say mate.


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## Pezza4u (Jun 7, 2007)

theshrew said:


> I have to agree with what you say mate.


So you understand why tracking is a complete waste of money and pointless then? 

Alot of people don't see the point in getting a geometry done mainly cos they have never heard of it as the industry term is 'tracking'. The second reason is they don't understand the differences between the two IMO and just go for the cheaper option.


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## Dipesh (Oct 12, 2007)

Normally people round here call geometry, tracking!

I just had mine done on the EK9 yesterday. Fantastic place £35


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## Nanoman (Jan 17, 2009)

Thanks Pezza! I knew there was a difference but wasn't sure what the difference is..

I saw a link somewhere that showed you which garages in your area have the proper equipment for doing geometry but can't find the thread. Anyone got any ideas?


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## Pezza4u (Jun 7, 2007)

grantwils said:


> Thanks Pezza! I knew there was a difference but wasn't sure what the difference is..
> 
> I saw a link somewhere that showed you which garages in your area have the proper equipment for doing geometry but can't find the thread. Anyone got any ideas?


www.alignmycar.co.uk :thumb:


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## Nanoman (Jan 17, 2009)

Pezza4u said:


> www.alignmycar.co.uk :thumb:


Thanks Pezza!!!


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## vroomtshh (Nov 23, 2009)

Dipesh said:


> Normally people round here call geometry, tracking!
> 
> I just had mine done on the EK9 yesterday. Fantastic place £35


For £35, I would suggest that what you have had done is tracking, not geometry.


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## Nanoman (Jan 17, 2009)

I just got quoted £60 for full geometry using the hunter equipment.


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## Dipesh (Oct 12, 2007)

vroomtshh said:


> For £35, I would suggest that what you have had done is tracking, not geometry.







































Don't look like tracking to me...


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## Pezza4u (Jun 7, 2007)

grantwils said:


> I just got quoted £60 for full geometry using the hunter equipment.


That's usually the minimum you will pay for one, upto £150+ depending on the car and what's adjustable. Some cars need to have extra weight added to them and/or a full tank of fuel, german cars for example need this.

They might have the hunter equipment but it's also how knowledgeable the operator is. It's worth trying to get some recommendations for the place you got quoted at first


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## Pezza4u (Jun 7, 2007)

Dipesh, that is a geometry as it covers toe, camber and castor but not a full one. Did they measure SAI and setback for example? What car was it for and do you have the before report?


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## Dipesh (Oct 12, 2007)

The car just went in as i had to change a rack gaitor and generally make sure everything is correct. 

That's all the paperwork that I got with it. What's sai and set back?


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## vroomtshh (Nov 23, 2009)

I stand corrected.

Thats very cheap for that though :thumb:


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## c928jon (Aug 2, 2006)

I do mine with some string, axle stands, spirit level and chalk


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## Pezza4u (Jun 7, 2007)

Dipesh said:


> What's sai and set back?


SAI is Steering Axis Inclination....the measurement in degrees of the steering pivot line when viewed from the front of the vehicle. This angle, when added to the camber to form the included angle causes the vehicle to lift slightly when you turn the wheel away from a straight ahead position. This action uses the weight of the vehicle to cause the steering wheel to return to the center when you let go of it after making a turn.

Set back (wheel base) is when either one of the front or rear wheels is set further back than the other wheel, length ways. Set back (wheel track) is how far apart width ways the wheels are. Set back is the different ways of measuring the wheels positions relative to each other.


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## Pezza4u (Jun 7, 2007)

c928jon said:


> I do mine with some string, axle stands, spirit level and chalk


If you're being serious my only reply is there's always one!!


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## c928jon (Aug 2, 2006)

Yep, deadly serious.

So do most of the racing teams in the UK, club level and higher.

We rough it out by stringing, then use tyre temps/ seat of your pants to tune it.

The Hunter machine uses the lasers and chequerboard wheel hangers, string = laser, steel rule = chequerboard.

I set a rebuilt porsche 996 up by the string method then had it checked by a hunter machine. I was bang on, green all over.

Done right accuracy to within .5mm is to be expected. 

Downside is it takes ages to set up, the laser gear is designed to set up really quickly.

The Hunter machine doesent know to dial out some of the neg camber for the banking on Rockingham International circuit though:lol:


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## c928jon (Aug 2, 2006)

What about corner weights?


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## shaqs77 (Jun 10, 2008)

my local place want £60


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## spitfire (Feb 10, 2007)

grantwils said:


> I just got quoted £60 for full geometry using the hunter equipment.


http://classic.multimap.com/clients...00&width=500&height=300&rt=browse2&reclimit=1

Pro grip are good. As said, it's not only the equipment but who's using it. Cheap too. And as someone said, he put weight in my bimmer boot. They use Hunter equipment.


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## Dipesh (Oct 12, 2007)

Pezza4u said:


> SAI is Steering Axis Inclination....the measurement in degrees of the steering pivot line when viewed from the front of the vehicle. This angle, when added to the camber to form the included angle causes the vehicle to lift slightly when you turn the wheel away from a straight ahead position. This action uses the weight of the vehicle to cause the steering wheel to return to the center when you let go of it after making a turn.
> 
> Set back (wheel base) is when either one of the front or rear wheels is set further back than the other wheel, length ways. Set back (wheel track) is how far apart width ways the wheels are. Set back is the different ways of measuring the wheels positions relative to each other.


He did have the plates on the side and turn the wheel's and also rolled it back and forward too? Perhaps this is what he was doing?


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## Pezza4u (Jun 7, 2007)

Dipesh said:


> He did have the plates on the side and turn the wheel's and also rolled it back and forward too? Perhaps this is what he was doing?


What he is doing here is Run Out Compensation (ROC) - The hunter looks for buckles in the wheels, acquires the size, checks the clamps for errors and the ramps horizon and zeros them


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## Pezza4u (Jun 7, 2007)

SAI is similar to castor and measured at the same time. Set back is used for diagnosing problems, so not always needed and it's not on the report below as my car is ok!


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## theshrew (May 21, 2008)

c928jon said:


> Yep, deadly serious.
> 
> So do most of the racing teams in the UK, club level and higher.
> 
> ...


I can see how you get it kinda correct with string etc certainly if you no what your doing thats fine for a road car. Most people coulnt tell you what camber or caster was let alone feel it was out.

I did a lot of R/C racing at a pretty high level certainly for racing them near enough just didnt cut it. I had my cars on the set up guages before every race to check everything over as very fine adjustments could make big changes to how the car felt.


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## SteveOC (May 26, 2007)

I had a geometry on mine at WIM yesterday and had 2 new tyres on the front (BlackBoots is what they call the tyre fitting side of the workshop IIRC).
I was somewhat cautious on the way home because of the new tyres, but after 50+miles of road/motorway driving I did give that car a little try out and it handles better (no more pulling to the right) and no loss of traction on fast corner exits like it did on occasion before). 

The saving on the tyre prices over Kwik-fit paid for my petrol costs to WIM/Blackboots, with the added bonus that they managed to change the tyres without ****ing up my wheels.:thumb:

I did ask the guy if it was just a matter of fiddling with things until the Reds turned Green, and he laughed at me and suggested that there was a fair bit more to it than that, although that was a starting point.
I have one of those sheets, but apparently my setup was very bad to start out and the modifications were limited to certain settings being adjusted to a maximum preventing any more comprehensive changes.

Steve O.


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## Pezza4u (Jun 7, 2007)

Steve what time were you there? Glad the car is sorted now, they know their stuff


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## ant_s (Jan 29, 2009)

just read this thread and glad i have as i thought i needed my tracking doing but im now not sure, ive had coil-overs fitted to my mk6 fiesta and think i must have hit a pot hole hard and now my steering wheel needs to be slightly turned to the right, instead of my hands being at 3 and 9, id say they are about 4 and 10, and my drivers side front has worn slightly more on the inside, so what would i need now?


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## SteveOC (May 26, 2007)

Pezza4u said:


> Steve what time were you there? Glad the car is sorted now, they know their stuff


Hey - I rang them after you posted in another thread, so thanks for that. :thumb:

I tried to check with Phil at Performance 5 to find out who he had recommended but they are not taking in work at the moment as they are really busy so not responding to email and I didn't hear back from him.
I did notice while I was there that the WIM site in Chesham was opened after I last spoke to Phil, so maybe Tony Bones relocated from somewhere else and that was where I had in mind?

I was booked in for a 1PM slot, but arrived at 12 as I allowed plenty of time for traffic, and I guess I left about 2:15-2:30.
There was another guy there in a green MX-5 who had travelled from Swindon (antipodean accent?) who came over for a chat.

I did want them to fit some flush valves to my wheels but they couldn't supply them and I couldn't source them in time despite spending hours on the net/phone/driving around. I may get some in off eBay for the future so I don't have to worry about lead times.

It's a pity I didn't know about them when my friend had a problem with a VW Golf that pulled to the right from New and was never sorted as VW maintained 'they all do that'. It's been sold now though.

Steve O.


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## Pezza4u (Jun 7, 2007)

ant_s said:


> just read this thread and glad i have as i thought i needed my tracking doing but im now not sure, ive had coil-overs fitted to my mk6 fiesta and think i must have hit a pot hole hard and now my steering wheel needs to be slightly turned to the right, instead of my hands being at 3 and 9, id say they are about 4 and 10, and my drivers side front has worn slightly more on the inside, so what would i need now?


How low have you gone with the coilovers and do you have or know if a camber kit is available for the fiesta? Best thing to do is register on the WIM forum and post a thread up, Tony will be able to advise you on what your options are 



SteveOC said:


> Hey - I rang them after you posted in another thread, so thanks for that. :thumb:
> 
> I tried to check with Phil at Performance 5 to find out who he had recommended but they are not taking in work at the moment as they are really busy so not responding to email and I didn't hear back from him.
> I did notice while I was there that the WIM site in Chesham was opened after I last spoke to Phil, so maybe Tony Bones relocated from somewhere else and that was where I had in mind?
> ...


So that was your MX5 I was having a nose around, I noticed it was very clean! You were the guy in black t-shirt and jeans? 

I was there from around 11:30am - 4pm getting my missus Peugeot 306 sorted, it was on the ramp before yours was done. I was wearing a baseball cap and walking around taking random photos and was sitting outside when you left! If I had known that was you I would've introduced myself :wave:

The guy with the green MX5 had all bushes replaced with poly ones, coilovers and rose jointed drop links...that's gonna handle extremely well now! :thumb:

WIM has been Tony's business for quite a few years but was originally based at STS in Watford and then Kiplings in Hemel Hempstead until he opened up his own place in Chesham. I noticed you signed up to the forum the other day, I hope you're finding it interesting?


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## SteveOC (May 26, 2007)

You jest - my MX-5 never seems to get washed, has never been machine polished and probably has no LSP on it right now, so I'd be too embarrased to admit to being on here while driving it- and I need to clean and seal the soft-top. Oh and the paint on the wheels is bubbling again and they were replaced under warranty a little over 2 years ago.
It has fortunately stayed clean underneath, as I had it undersealed when all the bracing went on because it gets driven in nearly all weathers.

I did see someone with a camera but wasn't really with it as I had been awake since 5 and took two and a half hours to get there. I dropped in to the in-laws in Uxbridge for a roast dinner on the way home and heard back that I apparently looked like **** when I arrived - which was nice.

I did notice the Ferarri parked right outside the front door - and the big WIM logo'ed truck parked out on the road though.

Steve O.


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## Pezza4u (Jun 7, 2007)

Mate compared to the motor I was in yours looked very clean...the 306 is swirled very badly but I've not had the chance to polish it yet.

Yeah that was me with the camera (never know what you will see down WIM), you were in the reception most of the time and I was outside snapping away! Although I did come in briefly to get a drink out of the vending machine.

The car parked outside the front door was a Lotus Esprit, which is Tony's, not a Ferrari...this one. I didn't see a Ferrari anyway 









The Dodge RAM is the company run around, which does about 8mpg but then it is a V10!!


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## SteveOC (May 26, 2007)

See I told you I wasn't with it - all I noticed was a red car, and then a couple of guys who worked there came in behind me talking about somebody who had a Ferarri and was selling it so I put two and two together and made five. 

The truck was parked out on a corner on the entry to the estate when I drove in, which was handy as I clocked it before I knew where to go, but it was gone when I left.

Steve O.


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## ant_s (Jan 29, 2009)

Pezza4u said:


> How low have you gone with the coilovers and do you have or know if a camber kit is available for the fiesta? Best thing to do is register on the WIM forum and post a thread up, Tony will be able to advise you on what your options are


errrm i have gone down around 60-80mm im not too sure, thats front and back, and im not sure if there is a camber kit for the mk6 fiesta, but i have it booked in to get the tracking done on saturday so i will mention to them about getting my geometry done, or even of they can do it

thanks


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## Pezza4u (Jun 7, 2007)

ant_s said:


> errrm i have gone down around 60-80mm im not too sure, thats front and back, and im not sure if there is a camber kit for the mk6 fiesta, but i have it booked in to get the tracking done on saturday so i will mention to them about getting my geometry done, or even of they can do it
> 
> thanks


How long have you had the car lowered that much? You may not need camber adjusters, it would depend on the geometry report as to what the angles are currently on and whether the wear you have is caused by toe or camber.

I've had a look and you can get camber adjustable lower arms if you do need them from here - Link

I really wouldn't bother getting tracking done, save the money for a geometry. If you're not local to WIM or don't fancy the drive check the align my car website to find your nearest garage that will have the right equipment.


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## ant_s (Jan 29, 2009)

the car has only been lowered for about 3-4 weeks, and ok thanks so if i get a geometry report it may say i need camber adjustments to get it set correct again?


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## Pezza4u (Jun 7, 2007)

ant_s said:


> the car has only been lowered for about 3-4 weeks, and ok thanks so if i get a geometry report it may say i need camber adjustments to get it set correct again?


I would get the geometry measured to see where the angles are now sitting but I would imagine going as low as you have there will be some negative camber now. Best thing to do is keep an eye on the tyre wear, if you notice the inner edges going bald (smooth) then you would need a camber kit to stop/reduce it.


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## raj1vad (May 26, 2010)

thanks 4 clearing it up, i feel a little mroe informed, thanks


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