Steering Alignment (with Correct Data in Post 1) - Page 7 - Alfa Romeo Forum
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Originally Posted by kandlbarrett View Post
Ghostydog: did you watch then do the adjustments? All they need is a second pair of hands. One holding the frame in place with the bar and the second tightening the bolts. Pinch them up a bit at a time and it should stay in the right position.
He said to get the sub frame in the right position the holes in the subframe were covering the threaded inserts. Im sure he didnt rush it, i was waiting for the car in reception and was watching theough the glass and he was constantly working on the car and it took him best part of 2 hours.
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Ok silly question, I'm starting to understand all of this now with regards to the toe in/out but still puzzled over the camber. Old Engineer, ur toe figures look good ie almost close to 0, and thrust is also spot on at 0. But ur camber angles are up front are about -1 deg 20+ mins and rear RHS is -2 degs!

My brera manual states camber should be

-34' +/- 18' front, -56' +/- 18' rear.

Surely camber will also affect tyre wear no?
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It will round off the edge of the tread if you run too much camber, but won't rip the rubber off the way that running too much toe will.
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So ideally, we should be aiming to get the toe and camber sorted? Or is this impossible to do?
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Originally Posted by wlm8361 View Post
Ok silly question, I'm starting to understand all of this now with regards to the toe in/out but still puzzled over the camber. Old Engineer, ur toe figures look good ie almost close to 0, and thrust is also spot on at 0. But ur camber angles are up front are about -1 deg 20+ mins and rear RHS is -2 degs!

My brera manual states camber should be

-34' +/- 18' front, -56' +/- 18' rear.

Surely camber will also affect tyre wear no?
You're right. At the time we didn't have a method for sorting this but now we know the subframe can be moved. In practice, the camber makes very little affect on tyre wear because it is not 'dragging' the rubber just 'loading' the rubber. You'll see my postings on real tyre wear and it's now excellent.
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Been following this thread with much interest as my fronts are doing the usual inside wear right on the shoulder of the tyre, rest of is fine.

Took the details very kindly put up by OE to the only place i've been advised in Bristol that is any good and off they went. They set up the car to begin the process and said its nearly at zero toe now on the front, cambers are fine and I should leave it as it. They couldnt explain the tyre wear pattern.

Details were
Front L toe 0.0
Front R toe -0.3 (they said near on impoossile to adjust it significantly more than this)

Cambers at 1 degree.

Rear tyre wear perfect and even though the cambers were slightly out they said leave alone.

They didnt charge me to be fair and the car was being discussed by several of their techs for a good 15 minutes or so and on the ramp for over half an hour.

Any advice gratefully received??

Roads??......Where were going we don't need...Roads!!
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Any advice gratefully received??
What tyre pressures do you run?
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What tyre pressures do you run?
Just checked them, and yes they are a little low. Have just put them to 2.9 on front, they were at 2.4!
So calls into question the accuracy of my usual garage air line??
Enough to make a difference probably??
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What tyre pressures are recommended for the 19' Ti wheels? And does engine size (and hence total curb weight) affect tyre wear? I can imagine a 2.4 bearing more weight on the tyres compared to say a 1750Tbi.
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[QUOTE=Alfiefreak;4636484]Been following this thread with much interest as my fronts are doing the usual inside wear right on the shoulder of the tyre, rest of is fine.

Took the details very kindly put up by OE to the only place i've been advised in Bristol that is any good and off they went. They set up the car to begin the process and said its nearly at zero toe now on the front, cambers are fine and I should leave it as it. They couldnt explain the tyre wear pattern.

Details were
Front L toe 0.0
Front R toe -0.3 (they said near on impoossile to adjust it significantly more than this)
(Quote);

If this means 0.3 degrees toe-out, it is far too much, as it equals 18' - anyone with a bit of care and attention can get the setting to within +/- 5'.

As I have said before I get perfect tyre wear (better than on ay car I have owned for the lat 15 years), and despite using lower than recommended pressures, still find that the centre wears a bit more quickly than the edges.
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Quote:
Originally Posted by wlm8361 View Post
What tyre pressures are recommended for the 19' Ti wheels? And does engine size (and hence total curb weight) affect tyre wear? I can imagine a 2.4 bearing more weight on the tyres compared to say a 1750Tbi.
For a Brera:
Normal Loads:
2.7 Bar Front
2.5 Bar Rear


Full Loads:
2.9 Bar Front
2.7 Bar Rear

159/Brera list the same pressures for all engine & trim versions, they just differ for different tyre sizes.
However, for some models they do now list different pressures for different engines.
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I might get a 3.2 brera soon, but I thought the pressures should be like 2.3?? Thats atleast what my 159 manual stated, does the increased pressure help the performance a little bit scientifically speaking?
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Mine will be running on the sad ol 17 inch wheelies
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Quote:
Originally Posted by Benzina159 View Post
I might get a 3.2 brera soon, but I thought the pressures should be like 2.3?? Thats atleast what my 159 manual stated, does the increased pressure help the performance a little bit scientifically speaking?
Quote:
Originally Posted by Benzina159 View Post
Mine will be running on the sad ol 17 inch wheelies
17" on a Brera are 2.5 Bar front & rear (normal loads) or 2.7 Bar front & rear (full loads).

159 only use 2.3 Bar on 16".
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Will this be ok fr my Ti saloon?

Front toe 0 parrallel
Front camber set equal/equal via subframe adjustment

Total rear toe in 18' - 22' equal/equal
Rear camber –1 3’ 18’

Anything missing? Cars in the garage now n need to get info to em. Cheers
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Will this be ok fr my Ti saloon?

Front toe 0 parrallel
Front camber set equal/equal via subframe adjustment

Total rear toe in 18' - 22' equal/equal
Rear camber 1 3 18

Anything missing? Cars in the garage now n need to get info to em. Cheers
Should be fine, but remember that 18' - 22' toe-in on the rear is the total toe, not each side!
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Quote:
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Should be fine, but remember that 18' - 22' toe-in on the rear is the total toe, not each side!

Yea 9-11 each side
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Correct me if I recall this backwards.

Too much toe in wears outers and, too much toe out wears inners?

That being the case, I don't get why we are going for minus (toe out?) 5' when zeroed still causes slight inner wear?

I have to have missed something.
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Quote:
Originally Posted by TimboZero View Post
Correct me if I recall this backwards.

Too much toe in wears outers and, too much toe out wears inners?

That being the case, I don't get why we are going for minus (toe out?) 5' when zeroed still causes slight inner wear?

I have to have missed something.
Not quite understanding your logic. The second line is correct. The third sentence is wrong. The Alfa settings are for Toe-Out and this is normal on front wheel drive cars because the engine torque will cause the wheels to want to Toe-In. The standard Alfa settings causes inner wear because the Toe-Out is too much. Modifying back towards zero eliminates inner shoulder wear (not as you state).

If you want to go into more detail the real problem (or asset) is the 'fast rack'. Only slight steering inputs move the inner wheel dramatically so that it acts like an anchor as you go into the corner. The outer wheel is taking the weight of the car and doing most of the steering. The inner wheel is helping by dragging the car round.

So standard settings give a false sense of agility. The modified settings save the tyres.

Last edited by Old Engineer; 02-03-12 at 20:44. Reason: C orrected
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Quote:
Originally Posted by Old Engineer View Post
Not quite understanding your logic. The second line is correct. The third sentence is wrong. The Alfa settings are for Toe-Out and this is normal on front wheel drive cars because the engine torque will cause the wheels to want to Toe-In. The standard Alfa settings causes inner wear because the Toe-Out is too much. Modifying back towards zero eliminates inner shoulder wear (not as you state).

If you want to go into more detail the real problem (or asset) is the 'fast rack'. Only slight steering inputs move the inner wheel dramatically so that it acts like an anchor as you go into the corner. The outer wheel is taking the weight of the car and doing most of the steering. The inner wheel is helping by dragging the car round.

So standard settings give a false sense of agility. The modified settings save the tyres.
With negative scrub radius, universal on FWD cars for thirty years or so, power-on creates toe-out.

The object of toe-out is to increase the cornering effect from the inside wheel, without using too much ackermann compensation, which tends to corrupt steering 'feel'.

The fast rack is a red herring as the inside wheel 'drag' is, as explained above, a function of the ackermann angle. Since the inside tyre is more lightly loaded it needs compensation for the outside tyre generating maximum cornering force at a slip angle which can be as much as 5 degrees.

Most wear occurs during normal driving when the steering angles are small, hence the need for the front wheels to be parallel. It does seem that the 159, particularly in Ti form is very sensitive to the toe setting (possibly excessive bump steer?), and so when various people advise 0.00 (parallel), they really mean that. Despite what a garage may tell you, it really is not that difficult to get it spot-on. On my traditional Dunlop optical gauges it is quite easy to see the effect of adjustments of as little as 1 or 2 minutes.
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I have to disagree. The 159 is nowhere near negative 'King Pin' angle. Ackerman is a factor but the Alfa uses a much more agressive ratio than needed.
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Quote:
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I have to disagree. The 159 is nowhere near negative 'King Pin' angle. Ackerman is a factor but the Alfa uses a much more agressive ratio than needed.
Scrub radius is not entirely directly related to KPI, as influenced by hub carrier geometry and ET. When I have time and can face removing one of those horribly heavy wheels - I will check - certainly double wishbones make it easier to reduce the scrub radius, but since negative scrub radius helps with split mu braking, it is highly unlikely not to be negative. Will report in due course.

Still don't agree with you agressive steering ratio - can't see the the physics to justify. The 159 is not unusually quick, whereas the 156 was very quick, but I believe that did not have the same wear problem
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...The 159 is not unusually quick, whereas the 156 was very quick, but I believe that did not have the same wear problem
The 156 have exactly the same wear issue when set to too much toe-out on the front.
The Sportpack/Veloce settings were changed to 0mm toe on the front in 1999, but you still get people setting them to the original settings and ripping the inner edges off...
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Sorry to check this again as the cost of tyres here is ridiculous, so I have to buy them during my annual 6 Nations weekend back home in Wales, where they are half the price (and someone usually takes great joy in AO ticketing my french car lol).

Just to be sure I have the data provided 100% right now, the range per tyre is between 7minutes of toein and 3minutes of toeout ?

Edit : Just to be sure , this is for a 159Ti
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Just to be sure I have the data provided 100% right now, the range per tyre is between 7minutes of toein and 3minutes of toeout ?

Edit : Just to be sure , this is for a 159Ti
Forget "range" and set it to 0mm toe on the front.

SIMPLE
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