BamaQLD's 'It's getting there' Polo build

[Sydneykid]

Faaaark it has a lot of rear toe in, 8.1 mm

That's not at all unusual when you lower them, the geometry is deliberately designed to toe in on suspension compression. It's supposed to always understeer because that's where the safety stuff is, seat belts, airbags, compression zones etc all designed for frontal impact. Sideways or rearwards impact (oversteer) is not as safe. As a result they want the outside wheel to toe in when going around a corner. Lowering has same effect, except it starts off with 8.1 mm toe in (static) then gets even worse around corners. If it were me I'd be wanting to fix this now, first, everything else pales into insignificance. The rear camber is not terrible, but could do with a tweak while you are getting the toe done (same shims).

More camber on the front left is commonly a sign of wanting to help lesson the drift to the left caused by the road camber (so the rain water runs into the gutter). Personally I prefer more left front caster, it works better. But your car has more caster on the right front, ooops. So the first job is to at least equalise the camber, maybe by moving the subframe across to the right. If that doesn't help then adjusting the inner lower front control arm bushes, more on the right if possible, if not then less on the left.

Once the camber is sorted you will need to adjust the caster, 5.76 on the right is good if you can get the left to at least the same or preferably a bit more (say 6.0). If not then you'll have to take some off the right, (say 5.0), that's not ideal, but better than the wrong way around like it is now.

Next I'd adjust the toe, at the moment it has 2.1 mm toe in, when it should have 2.1 mm toe out minimum. Personally I'd aim for 4 mm toe out.

The problem is once you adjust the caster and toe you are going to have to go back and adjust the camber again because it will have changed. Then when you have adjusted the camber the caster will change, so you need to adjust that, etc. After a couple of goes at each it should be close enough on all 3.

The above is why wheel alignments take more than a "lunch time" to do. To get an unfamiliar car, that's badly aligned, first time, with all the adjustments available, spot on, from scratch, front and rear, takes me almost a full day. At workshop rates, say $80 an hour, that's $650 for a wheel alignment. Once I have done a car a couple of times it gets down to under an hour, but that's starting from reasonable settings. At the race track I can do a camber and/or toe adjustment in a few minutes, because I know what and how much each adjustment makes, so I don't need any gauges or measuring.

In wheel alignments you get what you pay for.


Cheers
Gary

[Stuwey]

Faaaark it has a lot of rear toe in, 8.1 mm

Mine had 11mm toe-in back in the day - I can certainly vouch that the Whiteline shims made a massive difference!

[simon k]

bizarre - I had mine done yesterday and it was 2.9mm total adjusted back to 2.3mm - factory spec wants 2.1mm - no idea how he adjusted it, but that's what she sheet says

so when you lower the rear end (or under suspension squat) the orientation of the mounts make the beam toe in? I guess it puts tension across the beam in some way too

[sambb]

when you lower, the rear beam moves past horizontal and starts to be angled up a fair way towards the wheels. If you look from the side the wheels actually will move forwards in the guards quite a bit. Its possible I guess that the angles on the stub axle will change as you rotate the beam forwards.

[BamaQLD]

After reading the back end of the thread there were a few people I never got back to, so apologies first up. I managed to get a photo of the Front rear control arm bush installed (in reply to Sams post 11/04). Unfortunately I cannot provide a good picture of the front control arm bush as it is 'hidden' behind the frame. I really should investigate this further when I get under there again to check what setting they are on.


Also still have to get some rear shims for the rear toe in. Whiteline no longer manufacture their version... how do the eibach shims perform, I know you had recently obtained a pair Simon?

As you may have read in my other 'clunk' post I have now installed the Stg1 ECS cluth kit and the vibra-technics gearbox/LHS engine mount. I really cant emphasise how much better the car feels now. Check/change your engine mounts if any are suspect!!
Old v New



So now I think I am ready for a stg2 tune (long time coming). I read a lot about Custom code on the forum and Gav is the man to talk with? Just wondering how I go about it, as always appreciate any advice.

Thought I'd throw in a couple of turbo 4 legends. This was from Morgan park raceway historics a few weekends ago. ****s Sierra and Seatons Cosworth.


Cheers.

[simon k]

Also still have to get some rear shims for the rear toe in. Whiteline no longer manufacture their version... how do the eibach shims perform, I know you had recently obtained a pair Simon?

Sam says they perform well, Gary vouches for them, but I tried to install some and wasn't comfortable.

this is what you're looking for

VW Polo Mk3 & Mk4 GTi Eibach Rear Camber & Toe Adjusting Shims PAIR! 5.75200K | eBay

edit: that listing says you can only get 1.5mm of toe change, so 3mm total once you do both sides. Even after installing you'll have 5mm toe in... yuck

[Sydneykid]

The Eibach shims are actually made by Specialty Products in the US https://www.spcalignment.com/
I was the Australian agent for SP back when I had my own business, the last time I checked Pedders had taken over. Maybe worthwhile trying your local Pedders. Polos weren't sold in the US so SP doesn't list them, but they should be able to help.

As a price comparison VW Polo Mk3 & Mk4 GTi Eibach Rear Camber & Toe Adjusting Shims PAIR! 5.75200K | eBay

It sounds like a small thing, correcting the rear toe (and camber), but it makes a huge difference for not a lot of cost in parts. Especially if you can DIY.

Cheers
Gary

[Sydneykid]

edit: that listing says you can only get 1.5mm of toe change, so 3mm total once you do both sides. Even after installing you'll have 5mm toe in... yuck

As I previously posted 8 mm is an unbelievable amount of toe in, it's either a bad reading or something is bent.

Cheers
Gary

[BamaQLD]

Sounds like I had better get a second reading on the rear toe in. I have had the car from pretty much new and never been in an accident or hit any gutters etc. So I hope nothing is bent. Might have to see a specialist to get this sorted out. I'm interested to feel the difference in the handling once it is corrected.

[sambb]

I have heard some pretty extreme numbers. Mine had 6mm toe in on one of the cars and guys have had, 8, 10+mm so it could be that we just have a seriously turd beam?
When my car was at pedders, I was able to pull down on the rear toe hook with the car on the lasers and you could see it toe in more as I swung off the back of the car - so Gary is right, more compression or more lowering exaggerates the toe in. So choose your rear ride height first, then get your toe numbers at that height and we can tell you what numbers to set your toe/camber shims to to get the angles you need. You then can bung them in or hand them to a pro to do for you, but I'd be wanting a proper proper aligner, basically a race shop doing it, not a retail aligner or they'll bugger it up or just tell you what you are doing is wrong and overrule you. It was as big a change as a rear bar going from miles of toe in even to zero toe. Going toe out makes it able to keep up with modern hatches no prob.