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Discussion Starter · #1 ·
Chaps,

I have recently had Konis and PI springs fitted & front and rear poly bushes. I also had new mounts and other bits replaced. Had the tracking checked this morning as per advice from the guy who fitted the stuff and it was a mile out.

Question is, what do you think I should get it set to? I thought that Abbott set their 9000's to +1 on fitting front wishbone bushes. Is that right?

Steering feels a little heavier than before, I have to say - does that mean that the setting is wrong? Mark, as I think you have a similar suspension setup, do you know what yours are set at?

Any advice would much appreciated!
 

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I recently had mine checked and set to the standard spec. There isn't actually an awful lot you can adjust on the 9k setup- basically just toe in IIRC.

Mine was a bit out, and did feel better afterwards
 

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Discussion Starter · #4 ·
Mark, forgive my stupidity, but what does tow-in IIRC mean? Should I just get them to set to normal, rather than +1, then? I am assuming that steering tow-in means tracking?

Guy at the tyre place rekons that lowering suspension messes up camber and that it will increase tyre wear. 'So will 300bhp', I says!
 

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If
I
Recall/remember
Correctly

You adjust toe in/out to get your wheels parallel and straight ahead with the steering wheel in a central position.

Diagram below or steering geometry



9000's don't have adjustment for caster or camber. Toe in & out is just about all you get...
 

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With all the rubber in the suspension, the wheel attitude changes all the time. I was told that the toe-in toe-out angle was the manufacturers best guess at a setting, made when stationary, that would produce wheels that ran parallel when on the move.
 

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Discussion Starter · #7 ·
Erh, forgive me for being an idiot, but is tow-in what you alter when you change the tracking - ie. the rod that the bloke clamps his molegrips on? Or is this something else that you adjust?

I will try to get along to the Saab meet so that someone can see if my steering differs to theirs. Assuming that I haven't sold it before then, that is!
 

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JezF

Yes, toe in/toe out is adjusted by locking the tie rod with a mole grip and then adjusting the nut at the tie rod end. This shortens or lengthens the tie rods which are at each end of the steering rack.

cheers
 

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Discussion Starter · #11 ·
I told the garage to set the tracking to +1. Is that +1mm, then, or something completely different? Have to say that the car seems to corner better now, albeit I have only briefly driven the thing.
 

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Originally posted by JezF:
[qb]I told the garage to set the tracking to +1. Is that +1mm, then, or something completely different? Have to say that the car seems to corner better now, albeit I have only briefly driven the thing. [/qb][/b]
Yes you are correct.And a +toe measurement is normal for a front wheel drive car as under acceleration the wheels tend to try and drag themselves to a negative toe.
I am going to take my car into work soon and do a proper computerised 4 wheel alignment on it.I will take some pics and add some text to explain all the measurements and what they do in respect of drivability.I have spoken to Leon and he seems pleased to post the article on www.saab9-5.com (if it's any good ) I hope it will help to explain the subject of steering geometry.
 

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Originally posted by Derek:
[qb]Standard toe-in is 0 to 1/2mm or 0 to 12'. Although I believe some set turbo models to 1mm toe-in. [/qb][/b]
It's actually 1.5mm +/- 0.5mm. Abbott specify less toe-in with their poly bushes because they are stiffer and allow less movement under acceleration/braking, so less toe-in is required to compensate for that movement.
 

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Discussion Starter · #14 ·
So, Bill, bearing in mind that I have Superflex front and rear wishbone bushes, do you think that +1mm is about right?

Having now driven the car 60 miles last night, I can report that the correction in tracking has done miracles to the handling & to traction. In conjunction with the new top suspension mounts that were fitted last week, the car's handling has improved beyond all recognition - John, I need to take you for another drive!

It inspires confidence in the way it did not before.

I was advised by the garage to check the tracking after 500-1000 miles of fitting the new suspension. All I can say is if you do similar work, you must do the same. My tracking was checked 6 months ago, but after the new bits were fitted, it was out by 5mm.
 

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Originally posted by JezF:
[qb]I was advised by the garage to check the tracking after 500-1000 miles of fitting the new suspension. All I can say is if you do similar work, you must do the same. My tracking was checked 6 months ago, but after the new bits were fitted, it was out by 5mm. [/qb][/b]
I do hope the Garage did mean have it re-checked? after 500-1000 miles.If you carry out any work on the suspension it should be aligned straight away(Well after a quick drive to settle the bushes)even a new bottom ball joint or top mount can throw the toe out a mile! As well as caster/camber

If I also had to give advice about when to re-check I would say 100 max 200 miles as 500-1000 miles could destroy a couple of tyres if the geometry is out!
And I would think with poly bushes if the standard is 1.5 +/- 0.5mm.I would have thought you could go as low as +0.5mm? But I should think 1.0mm would be just fine.
 

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Originally posted by JezF:
[qb]So, Bill, bearing in mind that I have Superflex front and rear wishbone bushes, do you think that +1mm is about right?[/qb][/b]
I'd say it was fine. I once tried to draw Ed Abbott on an opinion as to whether I should set the alignment with Superflex bushes the same as he would set it with the Abbott bushes. He wouldn't commit himself.

I've driven my Aero at both 1.0mm and 1.5mm and really notice very little difference, but my opinion would be that the Superflex bushes will have a similar effect on the suspension to the Abbott bushes, so going with Abbott's recommendation seems to make sense.
 

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Bill just a thought,but if the manufacturers tollerances with rubber bushes are 1.5mm+/-0.5mm that leaves the minimum tollerance +1mm. So with the poly bushes I would expect far less flex,And as we know the toe setting is an educated estimate (in theory) for the correct toe when not under hard acceleration or braking.so working out that that a zero toe measurement is in theory what is needed when not under any load apart from tyre resistance am I wrong in thinking that a lower toe setting could be be used? as in +1.0mm +/-0.5mm? I do not know the answer and I'm only guessing but I would have thought with the upgrade this would work this way? So would a +0.5mm toe setting make a difference? I know what your saying but you are still keeping within the manufacturers tollerances with rubber bushes and with poly it should change,What do Abbott set the toe to? could it even be a zero toe? I'm not sure myself but what do you think?
 

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Abbott set the toe to 1mm with their bushes because that's what they arrived at after testing, 1.5mm with anything else because that's the Saab spec.

Abbott's testing showed less tyre wear with their bushes when set to 1mm rather than 1.5mm.
 
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