tracking and camber figures

[Rob_B 0]

ive been having a few handling issues of late, where the car wanders all over the road and seems be be thrown off line more than I remember. I know that having lowered suspension and bigger/wider wheels will make it bump steer a fair bit. however, i'm sure that its worse than usual.

Anyway, i've changed both bottom ball joints (genuine), both track rod ends (genuine), have poly bushes throughout the front end, polybushed the rear axle, had the 4 wheel allignment done and fiddled with the tyre pressures.

 

so after doing the above and having the tracking done (STS Tyre Pros) ive got these figures and it still doesn't feel 100%. Could someone look over the figures and see what they think please?

 

Front Left:

Camber: -0.40

Caster: 1.13

Toe: -0.02

 

Front Right:

Camber: -0.43

Caster: 1.41

Toe: -0.01

 

Rear Left:

Camber: -1.43

Toe: 0.24

 

Rear Right:

Camber: -1.17

Toe: 0.37

 

 

I know you cant really adjust the caster angles, so they must be out for a reason? like wise with the angles on the rear?

 

Thanks in advance,

Rob

[davidwort 0]

I'd prefer a bit more toe-in and camber on the front, would make it drive in a line better with more toe as they tend to pull out when you accelerate anyway, bit more camber would be nice in the corners.

[John-M 0]

I'd be interested to see what other people use, in terms of camber and toe-in/out settings.

 

How much adjustment is there at the back ? And do the rear settings make anywhere as much difference as the front ??

[Kevin Bacon 5]

I use 0 toe and -1 deg camber.

 

Standard camber for the VR6 is -1.2 but if you've lowered the car, reduce it to -1 or you'll scoff the inside edges of the tyres quicker than you'd like.

 

You can get geometry correcting shims for the rear, but I'd leave well alone unless it's miles out personally.

 

What the Corrado really needs, and responds well to, is more + caster. It's just not easy to achieve unless you use offset top mounts, but the bearings don't last long.

[Rob_B 0]

The camber and the toe are near as dammit to what the machine told the mechanic to set the figures at. These were based on it being a g60. So why would the caster angle be so far out on the left side?

[Kevin Bacon 5]

Caster is not adjustable on the Corrado, so could be a bent wishbone, worn wishbone bushes, bent subframe, bent floor.... could be any number of reasons.

 

0.2 out is enough to cause a pronounced pull in one direction though.

 

Toe and caster must be equal on both struts, camber is less critical.

[Rob_B 0]

Caster is not adjustable on the Corrado, so could be a bent wishbone, worn wishbone bushes, bent subframe, bent floor.... could be any number of reasons.

 

0.2 out is enough to cause a pronounced pull in one direction though.

 

Toe and caster must be equal on both struts, camber is less critical.

 

excellent! That's good information, now I know the direction I need to take.

Could shot wheel bearings on the front give me these sort of problems?

[Rob_B 0]

Had a quick look under the nearside, looks like a bent subframe on the leading edge wishbone bush. Not good!

[Rob_B 0]

right.... I went back to the tyre place and went through some stuff. they had the car up and the drivers side front wishbone, rear bush seemed to have more play in it than the passenger side. so, when applying some power, the wishbone would pull into the car and cause the car to pull to the right (what was happening).

the bushes were polyurethane so i had to have both wishbones changed so the bushes were the same. i had to have non gen items fitted as the tyre place would not fit anything i supplied.

ive driven the car a little bit and it seems better. it still feels a little twitchy on the back roads. I dont drive the car during the week (have van) so it must just be down to me forgetting how the car feels from week to week.

will keep and eye on the situation.

the leading edge of the subframe looked like it had taken a knock, so they kindly addressed that situation.

i would normally change all that stuff myself, but its such a pain (and expensive) getting it tracked up each time you change something that i though f**k it and let someone else play under the car!

[Kevin Bacon 5]

Yeah knackered bushes would cause that. I guess the ideal solution would be a s/hand and straight subframe and R32 / TT rear bushes as they're solid rubber and don't allow the strut to move under hard braking and acceleration, but cool, glad it's improved at least.

[herisites 0]

What the Corrado really needs, and responds well to, is more + caster. It's just not easy to achieve unless you use offset top mounts, but the bearings don't last long.

 

Or just don't want to turn! :brickwall:

[Rob_B 0]

Yeah knackered bushes would cause that. I guess the ideal solution would be a s/hand and straight subframe and R32 / TT rear bushes as they're solid rubber and don't allow the strut to move under hard braking and acceleration, but cool, glad it's improved at least.

 

 

you know far too much!! :) but where would we be without you! :salute:

[Rob_B 0]

I think I've finally got this one nailed now!

Aftr having non gen wishbone buses fitted, the car handled better briefly. So I dropped it off at a vw specilist in the area and he had a good look. He concluded that the wish one bushes that were fitted still had too much movement. So he fitted genuine Audi tt bushes (like Kev said) and problem solved!

Corrado feels much better again!

[Guest]

Re the castor figures.

The VRs target castor is +3. 25' -30 / +30 but mine has just had a 4 wheel alignment and reads as +1. 57 & +2. 17.

 

Robs are even less than mine.

What's going on. How on earth can you get +3. 25?

[Kevin Bacon 5]

If your caster is half what it should be, either something is severely worn, or the alignment machine isn't accurate.....or perish the thought....the bodywork or subframe aren't straight :?

 

The angle and position of the turret cup (what the TM sits in) in relation to the hub's centre line determines the caster, and to a lesser extent, the top mounts and wishbone bushes need to be in good nick to hold the strut at the correct angle. Nothing else can influence the caster directly.

 

If the Caster is that far adrift, I would expect the steering to feel lighter and more vague than usual and have very weak self centering?

 

Good news Rob, glad it's sorted!

[Rob_B 0]

Good news Rob, glad it's sorted!

 

So am I!

have some nice new suspension on order now and will be replacing my tyres very soon so hopefully it will be bob on again!

So you think et30 will be ok on my car Kev? I think that should clear the coilovers ok?

[Stonejag 10]

I use 0 toe and -1 deg camber.

 

Standard camber for the VR6 is -1.2 but if you've lowered the car, reduce it to -1 or you'll scoff the inside edges of the tyres quicker than you'd like.

 

You can get geometry correcting shims for the rear, but I'd leave well alone unless it's miles out personally.

 

What the Corrado really needs, and responds well to, is more + caster. It's just not easy to achieve unless you use offset top mounts, but the bearings don't last long.

I've got two ruined front tyres (inside edges worn right through) and the most recent one is only three months old :( Been getting a bit of vibration at speed recently so having the cords hanging out's probably not helping..!

 

The last place to set the geometry up was the same garage that nearly killed me with loose wheel nuts that also smashed my engine plastics, ripped the ends off my HT leads by pulling the wire, cracked my water pump, tore my aux water pump mounts etc etc etc so I'm pretty sure they set it up wrong.

 

What do I need to tell the tyre place to get it done properly first time, just the target toe and camber from above? I'm on 195/45/16s with approx 40-60mm drop (not sure how much, it's cranked up 45mm from where it was when I bought it...). Had new top mounts all round (Febi) and new rear beam bushes (also Febi) at around the same time as swapping the fixed Koni shocks for JOM coilovers about this time last year so hopefully they're still OK. Any tips would be most welcome, aiming to get it done Friday morning...

 

Cheers :)

 

Stone