Steering Alignment (with Correct Data in Post 1) - Page 4 - Alfa Romeo Forum
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Status: 159 2.4 20007 plate 19,500 DPF/EGR by Adie (AHM)
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I will definately post before and after figures and they have stated that they are happy for me to witness all the work.

Their responce to the subframe query was that as a body repair shop this was normal type work for them. As above I will update after 29th.

As a "time served" (real old fashioned apprenticeship) ex-mechanic I will be keen to see how it is done and what care and accuracy they work to or if I need to intervene!

Update after 29th.

PS: Autocolour are, I believe, Nationwide.
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My S had some 'interesting' suspension settings on delivery, withe the camber as well and the toe setting being out of spec. On both axles.

The camber was fixed by a combination of using the right figures (replacement of front suspension components didn't sort it) and adjusting the rear camber followed by the toe setting front and rear. Interestingly, although there is no front camber adjustment (and the subframe is 'pinned' to the chassis so won't move even if you slacken the bolts), levelling up the rear sorts the front too.

One other thing to note: It you have an S (and possibly a Ti) the car sits lower, so will come with more camber as standard.
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Originally Posted by 2ndtimearound View Post
...although there is no front camber adjustment (and the subframe is 'pinned' to the chassis so won't move even if you slacken the bolts), levelling up the rear sorts the front too...
Even if it's 'pinned' there will be movement.
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I assume a place like AHM would be able to do this also?
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Quote:
Originally Posted by Old Engineer View Post
Even if it's 'pinned' there will be movement.
There will be - but not enough to remove over a degree of imbalance in the front camber from side to side.

Relax and take a few deep breaths - it wasn't a dig at your earlier comment.
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On my 159 SW, we were easily able to correct a left/right front camber imbalance of just under half a degree by moving the subframe- there was still some more 'adjustment' left as well. There was also enough fore/aft play available to correct and equalise the KPIs at the same time.
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on my 4th geometry alignment in 4 months, is there anywhere in the world that can set geometry correct AND have the feckin' steering wheel pointing straight????? on my 3rd garage now (if you want to know where to avoid in oxfordshire, including 2 supposedly well regarded garages then let me know!) and having just had it supposedly set right this morning on the drive to work its still wrong, so have to go back later, again. It just seems to crab to the left in all conditions. So frustrated right now.
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Quote:
Originally Posted by cambio View Post
on my 4th geometry alignment in 4 months, is there anywhere in the world that can set geometry correct AND have the feckin' steering wheel pointing straight????? on my 3rd garage now (if you want to know where to avoid in oxfordshire, including 2 supposedly well regarded garages then let me know!) and having just had it supposedly set right this morning on the drive to work its still wrong, so have to go back later, again. It just seems to crab to the left in all conditions. So frustrated right now.
Have the garages you've used been doing a full 4-wheel alignment or just the front tracking? The reason I ask is because the 'crabbing' symptoms you're describing, together with the steering wheel being off-centre, are exactly what would happen if the front tracking was done correctly, but the rear wheels were pointing either left or right of where they should be. It could be either or both of the rears causing the problem.

What's required to correct this is a full 4-wheel alignment using (ideally) a Beissbarth alignment rig or (not quite as good) a Hunter alignment rig.

During a full alignment, the centre line of the car is 'discovered' by the computer and optics. The rear wheels' toe-in/out are then aligned to the virtual centreline to ensure the rear wheels aren't steering the back of the car. Next, the rear cambers are calibrated to give you optimal grip and tyre wear. Once the rear is all properly aligned, the front wheels' toe-in/out are aligned, based on where the rear wheels are pointing. This is done with the steering wheel locked in the straight-ahead position so it has to be properly centred once the alignment is completed. The front cambers can also be equalised and adjusted (within limits) by moving the front subframe. This will again give best grip and tyre wear.

The whole process can take a good hour or few as altering any one parameter on the suspension will have a knock-on effect on the others. The operator will likely have to go around the car two or three times before all the adjustments 'funnel-down' to exactly where they should be. This makes such an alignment costly, but well worth the trouble. Why? Excess tyre wear will disappear. The car will steer straight and true. The steering feel, turn-in, adjustability through a corner and overall grip will be vastly improved. Finally, your fuel consumption will be appreciably better as the car won't be dragging its tyres sideways along the road any more. The savings in fuel and tyres will pay for an alignment quickly enough, but the joy of having the car steering properly is well worth the financial pain anyway IMHO.

As to where to go. The only really top notch alignment specialist I know anywhere near you is Center Gravity near Tamworth. Chris who owns CG is practically worshipped amongst the Porsche community for his ability to set-up a car correctly. Whether he would do work on an Alfa, I'm not sure. Unfortunately I'm in Manchester so I guess my local alignment specialist (who also has a full Beissbarth setup) isn't going to be any use to you.

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Current Alfa: 159 Sportwagon 2.2 JTS
Previous Alfas: 156 2.5, 164 3.0, 75 3.0
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I'm only in Stockport, who do you recommend in Manchester?
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Quote:
Originally Posted by Ian_UK1 View Post
Have the garages you've used been doing a full 4-wheel alignment or just the front tracking? The reason I ask is because the 'crabbing' symptoms you're describing, together with the steering wheel being off-centre, are exactly what would happen if the front tracking was done correctly, but the rear wheels were pointing either left or right of where they should be. It could be either or both of the rears causing the problem.

What's required to correct this is a full 4-wheel alignment using (ideally) a Beissbarth alignment rig or (not quite as good) a Hunter alignment rig.

During a full alignment, the centre line of the car is 'discovered' by the computer and optics. The rear wheels' toe-in/out are then aligned to the virtual centreline to ensure the rear wheels aren't steering the back of the car. Next, the rear cambers are calibrated to give you optimal grip and tyre wear. Once the rear is all properly aligned, the front wheels' toe-in/out are aligned, based on where the rear wheels are pointing. This is done with the steering wheel locked in the straight-ahead position so it has to be properly centred once the alignment is completed. The front cambers can also be equalised and adjusted (within limits) by moving the front subframe. This will again give best grip and tyre wear.

The whole process can take a good hour or few as altering any one parameter on the suspension will have a knock-on effect on the others. The operator will likely have to go around the car two or three times before all the adjustments 'funnel-down' to exactly where they should be. This makes such an alignment costly, but well worth the trouble. Why? Excess tyre wear will disappear. The car will steer straight and true. The steering feel, turn-in, adjustability through a corner and overall grip will be vastly improved. Finally, your fuel consumption will be appreciably better as the car won't be dragging its tyres sideways along the road any more. The savings in fuel and tyres will pay for an alignment quickly enough, but the joy of having the car steering properly is well worth the financial pain anyway IMHO.

As to where to go. The only really top notch alignment specialist I know anywhere near you is Center Gravity near Tamworth. Chris who owns CG is practically worshipped amongst the Porsche community for his ability to set-up a car correctly. Whether he would do work on an Alfa, I'm not sure. Unfortunately I'm in Manchester so I guess my local alignment specialist (who also has a full Beissbarth setup) isn't going to be any use to you.
hunter 4 wheel alignment. The guy did spend best part of an hour this morning checking and so on, just when I drove it down the road the bl00dy steering wheel has to be held 5 degrees rhd to go straight. So with any luck it is right but the guy was having a numpty moment and forget to centre the wheel. If not, anyone wanna buy a 159?...
Might contact pete cambridge, probably worth a round trip to Warwick to defuse my irritation.
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4th trip back, everything checked ok, but steering wheel down to the right to go straight ahead, car drifting into the kerb but:- they cant check caster, and the front cambers are a bit out, about -1 degree on front left, just about right on rh. Given that the subframe was off a while ago for steering rack replacement it looks like a crowbar might be needed to sort perhaps as per Ian_UK1 s experience. Wooton Basset isnt too far away so i'll be interested to see if they sort it kandlbarrett, see if they'll give you a discount for recommending for another 159 to be done
otherwise i guess pete cambridge or autolusso might be able to help?
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Alignment is now done.

BEFORE READINGS
Note that before adjustment the front steering was off centre to right.

FRONT
Toe LH Off scale! RH +23'
Camber LH -56' RH -42'
Caster LH 308' RH 307'
NOTE: front toe with steering wheel offset and road wheels centred showed RH -9' and LH -10' so it was obviously last adjusted (poorly) to the old unrevised Alfa recommendations.

REAR
Toe LH 10' RH 14'
Camber LH -115' RH -49'


AFTER READINGS

FRONT
Toe LH -01' RH -01' (my instructed settings.)
Camber LH -50' RH -49' (manufacturers setting = -35' +/- 18')
Caster LH 308' RH 307' (manufacturers setting = 415' +/-18')

REAR
Toe LH 12' RH 13' (manufacturers setting = 13' +/- 18')
Camber LH -50' RH -49' (manufacturers setting = -40' +/- 18')

Adjustment comments:-
Note1: The standard settings on their machine for front toe is -08' so I instructed them to ignore the machine and set it to -01'.
Note2: Someone has previously removed and not replaced my engine undertray.
Front camber: as the distance between bottom suspension points is fixed the only option was to centralise the camber by moving the subframe sideways.
Front Caster: There was clearly 5 maybe even 10mm (front to rear) movement on the subframe but maximum movement only achieved a decrease in the measurement so no correction was possible. Also note that using all movement showed a change of 7 or 8' so that is relatively small and the maximum anyone can achieve.
Rear toe: Easy to adjust and now spot on.
Rear camber: LH now on maximum adjustment and RH on maximum adjustment before starting the work. There is very little room to get leverage on a spanner here and there was at least one set of skinned knuckles.


DRIVING BEFORE AND AFTER
Tyres are 235/45/18
Front (new less than 200 miles) Mitchelin Pilot Preceda
Rear (1/3 worn) Pirelli Nero Zero.

In the dead ahead position the car was fidgety and moved offline easily and frequently and suffered badly from “tramlining” in the lorry tracks on motorways. After making adjustment the car is very settled and doesn't give constant minor changes of direction on uneven surfaces and the tramlining is significantly reduced. It really is a transformation and my wife, it's her car, is really pleased by the improvement.
On very twisty roads and really pushing hard it doesn't turn in quite so instantly but the difference is small and the more relaxed and planted feeling makes up for this many times over.
Don't think we are laid back old farts looking for a cruiser and prefer lazy driving; that is not us and the car is driven spiritedly and enjoyed as Alfas should be and a comment from my wife after recent AHM DPF/EGR surgery was, “it gets to 130mph really quickly now, I wonder what it's real top speed is?”


FEEDBACK ON AUTOCOLOUR
They were good, pleasant and friendly guys. Paul did start off by telling me that I was not allowed to enter the workshop and could only watch from the entrance (H&S at it again) but by the end of the session I was almost under the ramp with them and it was reassuring to see the subframe bolts etc tightened with a torque wrench to the correct settings. However, if you do get stuck watching from the doorway it isn't a problem; the car is up in the air for the work so you can still see everything as it is done and see the readouts on the screen of the alignment machine from the same position.
Arrived at 09:10 and work finished at 11:05. I will now watch tyre wear but for the more relaxed driving and a much more settled car it is 100 + George Osbourne's cut very well spent indeed.

cambio -on my car does the wheel pull to the left either before or after my work, I really am not sure. Sometimes I think it does ever so slightly but most of the time I think not. Am I looking for something that isn't there and am being over sensitive? Probably!

Last edited by kandlbarrett; 29-10-11 at 13:41.
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Quote:
Originally Posted by kandlbarrett View Post
Alignment is now done.

BEFORE READINGS
Note that before adjustment the front steering was off centre to right.

FRONT
Toe LH Off scale! RH +23'
Camber LH -56' RH -42'
Caster LH 308' RH 307'
NOTE: front toe with steering wheel offset and road wheels centred showed RH -9' and LH -10' so it was obviously last adjusted (poorly) to the old unrevised Alfa recommendations.

REAR
Toe LH 10' RH 14'
Camber LH -115' RH -49'


AFTER READINGS

FRONT
Toe LH -01' RH -01' (my instructed settings.)
Camber LH -50' RH -49' (manufacturers setting = -35' +/- 18')
Caster LH 308' RH 307' (manufacturers setting = 415' +/-18')

REAR
Toe LH 12' RH 13' (manufacturers setting = 13' +/- 18')
Camber LH -50' RH -49' (manufacturers setting = -40' +/- 18')

Adjustment comments:-
Note1: The standard settings on their machine for front toe is -08' so I instructed them to ignore the machine and set it to -01'.
Note2: Someone has previously removed and not replaced my engine undertray.
Front camber: as the distance between bottom suspension points is fixed the only option was to centralise the camber by moving the subframe sideways.
Front Caster: There was clearly 5 maybe even 10mm (front to rear) movement on the subframe but maximum movement only achieved a decrease in the measurement so no correction was possible. Also note that using all movement showed a change of 7 or 8' so that is relatively small and the maximum anyone can achieve.
Rear toe: Easy to adjust and now spot on.
Rear camber: LH now on maximum adjustment and RH on maximum adjustment before starting the work. There is very little room to get leverage on a spanner here and there was at least one set of skinned knuckles.


DRIVING BEFORE AND AFTER
Tyres are 235/45/18
Front (new less than 200 miles) Mitchelin Pilot Preceda
Rear (1/3 worn) Pirelli Nero Zero.

In the dead ahead position the car was fidgety and moved offline easily and frequently and suffered badly from “tramlining” in the lorry tracks on motorways. After making adjustment the car is very settled and doesn't give constant minor changes of direction on uneven surfaces and the tramlining is significantly reduced. It really is a transformation and my wife, it's her car, is really pleased by the improvement.
On very twisty roads and really pushing hard it doesn't turn in quite so instantly but the difference is small and the more relaxed and planted feeling makes up for this many times over.
Don't think we are laid back old farts looking for a cruiser and prefer lazy driving; that is not us and the car is driven spiritedly and enjoyed as Alfas should be and a comment from my wife after recent AHM DPF/EGR surgery was, “it gets to 130mph really quickly now, I wonder what it's real top speed is?”


FEEDBACK ON AUTOCOLOUR
They were good, pleasant and friendly guys. Paul did start off by telling me that I was not allowed to enter the workshop and could only watch from the entrance (H&S at it again) but by the end of the session I was almost under the ramp with them and it was reassuring to see the subframe bolts etc tightened with a torque wrench to the correct settings. However, if you do get stuck watching from the doorway it isn't a problem; the car is up in the air for the work so you can still see everything as it is done and see the readouts on the screen of the alignment machine from the same position.
Arrived at 09:10 and work finished at 11:05. I will now watch tyre wear but for the more relaxed driving and a much more settled car it is 100 + George Osbourne's cut very well spent indeed.

cambio -on my car does the wheel pull to the left either before or after my work, I really am not sure. Sometimes I think it does ever so slightly but most of the time I think not. Am I looking for something that isn't there and am being over sensitive? Probably!
Aren't most roads made with the centre slightly higher and the rest sloping away so that rain water will flow off? - a feature that will make all cars steer to the left when the wheel is released
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On very twisty roads and really pushing hard it doesn't turn in quite so instantly but the difference is small and the more relaxed and planted feeling makes up for this many times over.

That's exactly the result I had. I think Alfa do tune their pre-production cars for 'turn-in' without worrying about tyre wear. The new results are minimally different and streets ahead of the competition.
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Tyre Wear Update

I had a good look at my tyres today (mainly because the Rear O/S is getting low). Interestingly, at 25,000 miles, this is the only original tyre still on the car. They are all Pirelli P-Zero but the car had the steering alignment changed at 15,000 miles to the new settings. At this point it needed 2 new fronts because the inside edge was 'missing' and the rear N/S had already been changed for a puncture. It's now up to 25,000 and the story would be good apart from punctures. Here's the measurements...

Front N/S
Puncture Replacement at 19,000
Covered 6,000
Outer Middle Inner
6.5 6.5 6.5

Front O/S
Tracking Replacement at 15,000
Covered 10,000
Inner Middle Outer
5.0 5.0 5.0

Rear N/S
Puncture Replacement at 10,000
Covered 15,000
Outer Middle Inner
4.0 4.5 4.5

Rear O/S
Original
Covered 25,000
Inner Middle Outer
2.0 2.5 3.0

Last edited by Old Engineer; 30-10-11 at 20:51. Reason: Spelling!
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I have been thinking about the inability to adjust my caster angle or, more accurately, the very small change in caster angle that moving the subframe gave.

First some simple assumptions (I have not measured.)
Assume the top of the strut is fixed two feet (600mm) from the centre of the hub.
Assume the subframe movement was 1/4 inch (6mm.)
Trigonometry: the tangent of the change in caster angle (Opposite over adjacent) = 6mm / 600mm = 0.01. A tan value of 0.01 gives an angle change of 0.57 degres or 34 minutes.

Now even if the subframe movement was only 3mm (I am sure it was more than that though) the available angle correction would have been 3 / 600 = (tan value) 0.005 = 0.286 degres = 17 minutes.

Without measuring the components and movement I think 18 inches (450mm) strut to wheel centre and 1/4 inch (6mm) subframe movement is closer to the real values and that gives 0.76 degres or 45 minutes of caster adjustment. So worst and best case available caster adjustment should be somewhere between 17 minutes and 45 minutes.

Interesting! Is this just a case of other bushes flexing and affecting the readout thus not getting a true representation of what has changed. Certainly the best and expensive way to make suspension adjustments and be 100% sure they are settled at their correct value is make adjustment, road test, back on the machine, check readings, make adjustment, road test, back on machine, check readings, make adjustment, road test, back on machine..........

Now that is usually quite expensive and more than is normally done for a road car. If you are racing or driving exotica you might do it but not on everyday road cars. Thought provoking though!

NOTE: The maximum assumed value of 0.76 degree change, had it been in the right direction, would not have been enough to get the caster setting within manufacturers tolerance. Wonderful Alfa adding soul once again.

Last edited by kandlbarrett; 31-10-11 at 12:55.
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Quote:
Originally Posted by kandlbarrett View Post
I have been thinking about the inability to adjust my caster angle or, more accurately, the very small change in caster angle that moving the subframe gave.

First some simple assumptions (I have not measured.)
Assume the top of the strut is fixed two feet (600mm) from the centre of the hub.
Assume the subframe movement was 1/4 inch (6mm.)
Trigonometry: the tangent of the change in caster angle (Opposite over adjacent) = 6mm / 600mm = 0.01. A tan value of 0.01 gives an angle change of 0.57 degres or 34 minutes.

Now even if the subframe movement was only 3mm (I am sure it was more than that though) the available angle correction would have been 3 / 600 = (tan value) 0.005 = 0.286 degres = 17 minutes.

Without measuring the components and movement I think 18 inches (450mm) strut to wheel centre and 1/4 inch (6mm) subframe movement is closer to the real values and that gives 0.76 degres or 45 minutes of caster adjustment. So worst and best case available caster adjustment should be somewhere between 17 minutes and 45 minutes.

Interesting! Is this just a case of other bushes flexing and affecting the readout thus not getting a true representation of what has changed. Certainly the best and expensive way to make suspension adjustments and be 100% sure they are settled at their correct value is make adjustment, road test, back on the machine, check readings, make adjustment, road test, back on machine, check readings, make adjustment, road test, back on machine..........

Now that is usually quite expensive and more than is normally done for a road car. If you are racing or driving exotica you might do it but not on everyday road cars. Thought provoking though!

NOTE: The maximum assumed value of 0.76 degree change, had it been in the right direction, would not have been enough to get the caster setting within manufacturers tolerance. Wonderful Alfa adding soul once again.
The distance you need to measure for the basis of your calculations isn't to the 'strut top'. These cars don't use McPherson struts, the mount you can see under the bonnet is only the top of the shock absorber. As the car uses a double wishbone suspension setup, the relevant distance to measure is from the top to the bottom wishbone balljoints. In effect the top wishbone is fixed and you're moving the lower wishbone left/right and front/back by moving the subframe. The difference in angle will be calculated from the movement of the bottom balljoint relative to the fixed, top balljoint. This is a lot shorter than the distance you measured, hence you're actually geting a much bigger angular change per mm of frame movement than you thought.
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Ian, Thank you, I hadn't looked at the suspension set up closely enough. As you rightly point out the reduced measurement between top and bottom wishbones should increase the angular change for caster probably above the maximum assumed 0.76 degres that I calculated.
So the core question remains why did the Hunter equipment only show a caster angle change of about 6-8 minutes between the subframe being fully forward and fully retracted toward the rear of the vehicle?
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Quote:
Originally Posted by kandlbarrett View Post
Ian, Thank you, I hadn't looked at the suspension set up closely enough. As you rightly point out the reduced measurement between top and bottom wishbones should increase the angular change for caster probably above the maximum assumed 0.76 degres that I calculated.
So the core question remains why did the Hunter equipment only show a caster angle change of about 6-8 minutes between the subframe being fully forward and fully retracted toward the rear of the vehicle?
I'm not certain about this, so hopefully someone else can chime-in to comment, but from what I understand, caster angle can't be measured directly unlike camber or toe - it is calculated by the alignment rig's computer from data measured as the wheels are turned by the steering.

I do know the Beissbarth rigs can't 'measure' caster particularly accurately in standard form. To get a more accurate caster reading, Beissbarth users have to buy some additional, trick (and expensive) slide plates that contain motion/pressure sensors. These measure how the wheel moves with steering and send that data back to the rig's computer in addition to the 4 main wheel sensor pods. Obtaining accurate and meaningful caster measurements appears to be a very complex exercise!

Whether the Hunter kit is able to measure caster in any meaningful way from the cameras on the top of the rig, I'm not sure. TBH I'd guess it only makes a very approximate stab at it and that's what you have in your results.

At the end of the day, irrespective of any alignment rig's print-out, the calculations don't lie. If you move the lower wishbone x mm backwards, you get a fixed angular change of y over a given height. End of. If you know how far the subframe moved back, then you can at least calculate the real change made to your car, if not the absolute value of the caster angle.

Last edited by Ian_UK1; 02-11-11 at 16:29.
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Ian, you are correct. After lots of reading I now know that the equipment can't directly measure caster. It is calculated from the effective change in camber as the wheels are turned through a known angle. What is actually done is that the wheel is turned 20 degrees (or other fixed angle) either side of straight ahead. By measuring the camber at each point the caster can be (is) calculated. As you have hinted there are a number of issues doing it this way (flexing of rubber bushes affecting readings, accuracy / care of the operator, large multiplying effect that minor errors have in the equations used etc.) that mean the accuracy of the caster angle is questionable. What tolerance good equipment has and how well it controls careless operators I don't know.

An example of the effect caster has and how it changes camber when the wheel is turned is the front wheel of a bicycle. In the straight ahead position the front wheel of a bicycle has no camber. Turn the handle bars 90 degrees and you can see that the camber now equals the caster. OK you cant turn a car wheel 90 degrees but by turning it through a known angle makes it possible for pointy headed boffins and their machines to calculate the caster.

Autocolour did not turn the wheels after moving the subframe so I now know the caster was not recalculated. Conundrum solved! Had I known then how caster is measured (calculated) I would have made them go through the process to measure it with the subframe fully forward and fully aft just to know what range of adjustment is possible. Autocolour's previous rating is downgraded and I will discus it with them!

So what caster angle do I now have? Well I can't be 100% certain but I do know the subframe was at the rear of it's maximum travel before adjustment and it still at the rear of it's maximum travel so caster should be unchanged from the original 3 degrees 08 minutes.

Finally, my wife drove from Swindon to Oxford today using A420 to get there (fast sweepers and a few twisties) and A34/M4 for the return journey and has come back singing praise for the improved driving pleasure and less skittish car that she has.

Last edited by kandlbarrett; 02-11-11 at 22:15.
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OK, i'm just confused now

Can someone please just clarify what the settings should be for a 2.4 Ti Q4 please?
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Quote:
Originally Posted by kandlbarrett View Post
Ian, you are correct. After lots of reading I now know that the equipment can't directly measure caster. It is calculated from the effective change in camber as the wheels are turned through a known angle. What is actually done is that the wheel is turned 20 degrees (or other fixed angle) either side of straight ahead. By measuring the camber at each point the caster can be (is) calculated. As you have hinted there are a number of issues doing it this way (flexing of rubber bushes affecting readings, accuracy / care of the operator, large multiplying effect that minor errors have in the equations used etc.) that mean the accuracy of the caster angle is questionable. What tolerance good equipment has and how well it controls careless operators I don't know.

An example of the effect caster has and how it changes camber when the wheel is turned is the front wheel of a bicycle. In the straight ahead position the front wheel of a bicycle has no camber. Turn the handle bars 90 degrees and you can see that the camber now equals the caster. OK you cant turn a car wheel 90 degrees but by turning it through a known angle makes it possible for pointy headed boffins and their machines to calculate the caster.

Autocolour did not turn the wheels after moving the subframe so I now know the caster was not recalculated. Conundrum solved! Had I known then how caster is measured (calculated) I would have made them go through the process to measure it with the subframe fully forward and fully aft just to know what range of adjustment is possible. Autocolour's previous rating is downgraded and I will discus it with them!

So what caster angle do I now have? Well I can't be 100% certain but I do know the subframe was at the rear of it's maximum travel before adjustment and it still at the rear of it's maximum travel so caster should be unchanged from the original 3 degrees 08 minutes.

Finally, my wife drove from Swindon to Oxford today using A420 to get there (fast sweepers and a few twisties) and A34/M4 for the return journey and has come back singing praise for the improved driving pleasure and less skittish car that she has.
Less caster tends to make for steering that tramlines/follows camber changes, and generally is a bit fidgety on motorways compared to the same set up with more caster.
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Red 2.4 159 Ti

If I was to print off Old Engineers attachment and take that to my garage would they be able to put the same settings on my Ti?

Is this the setup to go for? One of my tyres is nearly done due to uneven wear. Not picked the car up yet, but this will be the first job.

George K - is your setup the same as this? Pretty much?

I don't really understand it at all.
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Is there an official document stating that valves should not as per the databook supplied by alfa romeo for TI models?
I have changed mine, stting it to "0" as per old engineer and many others recommandations... but cannot make it at alfa, because they remain stuck to -7 +/-4

I have found that behavior is different now at "0". Not so stuck to the ground as before, with slighly less roam noise as a good point.
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