26 replies to this topic

[Marco Polo]

Hi folks As I got my car just 2 month ago, I don't have so much knowledge on its alignment numbers... My next track day is Sept. 7 and I go to the alignment shop next Wednesday... What are the factory recommended alignment numbers ? (I don't have the car manual... :ph34r: ) For the people going on-track, what alignment numbers are you using ? (with the common Bridgestone RE040) Thanks in advance

[Ricky2772]

dunno my "numbers, since I modded one step at a time, test-driving it everytime.... all I can tell you is that I run a slightly open toe at the front, close toe at the rear, all the camber shims removed at the front and 4 shims removed at the rear.... all this along with yoko 048......

[Steve Crisp]

So Ricky, Does removing the front camber shims reduce the camber or increase it? (Hopefully not a dumb question, I guess it depends whether they are on the top arm or the bottom one!). Steve

[Ricky2772]

mmmmm....they look like this, /---\ (seen from front-rear)

[cheeky_chops]

mmmmm....they look like this, /---\ (seen from front-rear)

so this is what "scared stiff" fo in the UK?

How about a "How to remove your shims" guide Ricky?? Is this ok for road use?

[Ricky2772]

so this is what "scared stiff" fo in the UK?

How about a "How to remove your shims" guide Ricky??      Is this ok for road use?

that must be it, can't see what other mods could they come up with....

easy job, 2 big allen bolts behind the hub to loosen up, need only to fully remove one though.....(as it can be seen in the pic....)
slide out the desired amounts of shims, then test-drive it....
beware that modding the camber usually requires modding the toe as well....
more camber makes the front-end bite the turns better, so it might surprise the unexperienced with too sudden, understeer-free turn-in....that is why you want to open the front toe a bit to soften the steering input.... along the same line, closing the rear toe will add some stability to the rear-end, making it less jumpy and unpredictable...

just like for the pads replacement, this is something that is not to be done by wanna-be do-it-yourselfer, if you cock-up or forget to tighten up something it might lead to disaterous consequences.... :ph34r:

as a side note, the Opel monkeys proved once more their unparalled ineptitude, when reinstalling the rear hub after fixing the gear leak....while doing so, they overtightened the two allen bolts, even ruining the inside pattern, so when I tried to undo'em to change the camber they where soon hopelessly rounded....
....had to resort to a local mechanic to get'em loose...he had to sweat and curse for more than an hour, only to find out that those idiots used threadlock fluid on'em!!!

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Edited by Ricky2772, 31 August 2003 - 11:45 AM.

[Steve Crisp]

A few questions if I may: - How do you change the castor angle? What effects does that have? Am I right in saying that castor changes the vertical axis as viewed from the side of the car, and camber changes the vertical axis as viewed from the front of the car? I thought I saw mentioned somewhere that changing the castor in some way reduces the amount of feedback through the steering? I want to understand the difference between the factory NA geometry, and the VXT geometry, and why they changed it. The reason is, I'm just about to fit VXT springs and dampers to my NA. I don't need so much "information" for just road use, and the NA gives too much (for me)!

[PaulCP]

Fitting the Spax coilovers and lowering by 15mm on mine has reduced the amount of pull and feed on the steering wheel on mine. Although the rear toe was adjusted by Scared Stiff i don't think that they adjusted the front settings since they were deemed to very close to their ideal (apparantly unlike others that they have done) Not sure about the effect of fitting the VXT dampers & springs since i thought that they were changed to suit the heavier car but could be wrong Paul

[Ricky2772]

A few questions if I may: -

How do you change the castor angle? What effects does that have?

cannot help in that, I was always advised not to mess with caster....it has to do with the angle between the hub and the susp. arms....not easy to fully understand....

unless dealing with a racing car, working on camber and toe alone takes care of 99% of driving needs....

[cheeky_chops]

Err, i think i will take your advice Ricky and leave it to a specialist

[Jase_MK]

This may be total b*llox and not at all applicable to cars but castor on a bike (the angle at which the forks head downwards) affects the steering. Vertical forks (90 degrees) would respond instantly to steering input but would so twitchy and impossible to ride. A really relaxed angle (like a chopper) gives less twitchy steering and a smoother more stable ride but also crap steering response. I'm sure some of that applies to cars too.

[Ricky2772]

about the "obscure" castor, this is a pic from my tuning manual....

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[Ricky2772]

this is camber...

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[Ricky2772]

and this is toe:

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[Marco Polo]

More infos (concerning MX-5/Miata ) :

http://www.miata.net/garage/align.html

and

http://www.hummingbi.../alignment.html



But still no number.......

[cheeky_chops]

ahh, starts to make sense with a piccy and a few links!

[Steve Crisp]

I've just put VX Turbo front springs and shocks on my NA. I'm VERY happy with the result. It has indeed taken some harshness out of the front, but still feels as good as ever. This is an NA mod to be recommended if you're like me and do totally road. I might change the rear in total soon as well, but maybe I'll use the NA springs with the VXT shocks first, I haven't decided yet. The settings for the NA are: - Front ------ Camber -0.06 (+0.06/-0.12) Castor +3.48 (+/-0.12) Toe -0.20 (+/-0.20) Rear ----- Camber -1.48 (+/- 0.12) Toe 0.12 (+/- 0.20) Note: - For TOE, a positive value indicates wheels pointing inwards (converging), whilst a negative value is the opposite. Valid for cars with two passengers (70 kg each), and 3/4 tank of petrol. Does anyone know the VXT values???

[Steve Crisp]

I've just got these new values from the Vauxhall TIS CD. This is now recommending the following VX NA settings: - Front Wheels ---------------- Camber -0.1 (+0.1/-0.2) Caster +3.8(+/-0.2) Toe -0.03 (-0/+0.03) Rear Wheels ---------------- Camber -1.8 (+/-0.2) Toe +1.2 (+0.2/-0) A bit of a difference from the settings that were posted sometime ago on the Yahoo board. I shall pop down the local friendly tyre place this weekend and see what my settings currently are. The caster angle can be changed on the VX by adjusting the shims at the upper wishbone pivot points to the chassis. There are four, 1.5mm shims at both pivot points. You should not remove any of these spacers, but take a spacer(s) from the back of the assembly and place them at the front (for more caster) such that say, there are three in front of the bearing and one behind, etc. I've got the manual pictures if anyones interested. I am certainly going to get the geometry checked, and I'll do the caster if it's out. All bolts for pivot points and shock mountings are torqued to 45nm. Wheel bolts to 90nm.

[clipping_point]

Back Toe (per side): 0,18° Tolerance: +0,03° Max difference left/right: 0,03°

[Ricky2772]

I can add that for track purposes, maximum G's and grip are achieved eliminating ALL six camber shims. I tried in spa adding back a couple, but it was worse.... rear toe has to be IN. this was some heart-wrenching sight in the spa paddocks...

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