Camber Wear And Thoughts On Spacers

[No Crust Racing]

Firstly, I'm assuming this is a sign of not enough camber?

Car is a Silvia and has this setup with BC BR 8/6kg coilovers. Whiteline front swaybar 27mm, r32 gt-r rear swaybar. Stock castor arms. S15 rack/tie rods and gktech rear toe arms.

Driver: -2.75/1mm toe out
Pass: -2.75/1mm toe out

Rear- Camber/Toe
Driver: - 1.3/1mm toe in

Pass: -1.3/1mm toe in

Tyres are 595 RS-Rs

2 questions.

If I do need more camber, what's the easiest way to get it front and rear. Strut tops are maxed at front and I was going to raise the car a little to help get LCA's parallel and improve roll centres which means I'll lose a bit of camber.

I may get a little more camber in the rear but not much as the rear passenger side is closed to maxed due to what I suspect is bent hub. I was thinking either adjustable LCA bush for the front or slotting the shock mount hole. Not much I can do in the rear besides fix hub?

Also, spacers. Front wheels are close to shock, if I need more camber I'll need more clearance. Is a 10mm spacer front and rear going to be OK? If so what do I need to know about buying them? Stick with hub centric?

Or am I better off with something like this?

http://www.gktech.com/index.php/4x114-3-20mm-hub-centric-spacers.html

Edited April 25, 2015 by ActionDan

[GTSBoy]

You can get adjustable length lower arms.

[No Crust Racing]

I've seen those, but not heard good things?

[No Crust Racing]

Looking at these.

http://www.whiteline.com.au/product_detail4.php?part_number=KCA412

http://www.whiteline.com.au/product_detail4.php?part_number=W62544

[Duncan]

honestly I'd put some proper semis on it first, they will change what you need for camber anyway. You'll keep having problems and frustrations trying to track with road tyres.

[No Crust Racing]

For the money, these are very good and as they still have plenty of tread and this is budget motorsport, they will stay for now. Anything I add to the car now will help me later anyway.

After more reading it seems I won't need spacers anyway as I had misunderstood how the LCA bush adjustment will work, so if it clears now it will stay cleared.

That said, does that look like camber wear to you?

I have a infra red gun on the way also.

Edited April 25, 2015 by ActionDan

[warps]

That's not camber wear.

Camber wear happens on the inside of the tyre when you have too much negative, or outside when you have positive camber. It happens when these settings are used on the road over a long period of time.

Similar wear occurs much faster if you have excessive toe in (outside of tyre) or toe out (inside of tyre) as this is actually causing the tyre to scrub, which wears it out much faster.

What you have there is normal outside wear from cornering on the limit (as you guessed). Increasing negative camber will reduce this, again as you have guessed. Whether you can dial in enough camber to eliminate the wear, without starting to induce other problems (such as braking traction) is doubtful on road tyres.

-2.75 camber is reasonable for a street / track driven car, and you will obviously reduce the edge wear with higher camber settings, but that then will effect the wear rates for normal street driving, and possibly affect the way the car drives on the road. To eliminate it completely, you have to have the camber dialled in such that at maximum cornering force you have an even tyre load on the road. At anything less, you will have excessive camber, reducing the available grip. Like anything, this is a balancing act and a compromise.

As you probably know, castor and roll will have a big impact on how much dynamic camber the tyre sees under cornering. These can easily offset a couple of degrees of camber, so your static camber might not be the cause. Dialling in castor or reducing roll will both have an effect to reduce this wear pattern. Is this what you need? Can't tell as these might be optimum for giving you balanced handling already, or they might be completely off the mark.

Might be time to spend some track time with a suspension specialist who can help you dial the car in properly. Reading figures on an internet forum can only go so far to giving you the optimum balance.

The temp gun will only confirm what you already suspect, ie the outside edge of the tyres is getting hotter.

[No Crust Racing]

Thanks Warps. FYI This is a track only car and I realise I'm asking a lot of the tyres now, but given they still have plenty of meat, I'll keep going for now. They did not wear like this until I added the swaybars so I'm thinking that the sidewall is now being asked to work much harder and is rolling over. Also, if the car is too low, then as it squats the increased swaybar stiffness will actually cost me camber through a corner as the whole sub frame moves past it's ideal point.

After a bit more reading and discussion, this is my plan.

- Raise ride height front and rear to get LCAs flat when stationary and improve roll centres. As I understand it, this will cost me camber front and rear. (correct?) So I'll do this first and see what camber I end up with and decide if bushes/slotting subframe mounts is needed front and rear to get me back to where it was, I may actually back the camber off up front
- Get caster arms, aim for 7.5-8, pending clearance which should help dynamic camber up front.
- Make a call on rear camber amount pending changes to camber after ride height change and balance that with ability to put power down.

Thoughts?

[Dose Pipe Sutututu]

what LCAs are you running? are they stock?

If you're keen on increasing track, run S14/S15 LCAs then slap some spacers on the rear.

If you want something value for money other than the RS-R, look at Nitto NT05... Like the RS-R, not a true track tyre. If money permits, NT01

[No Crust Racing]

Stock LCA's, but as above, it seems camber is not my issue. I'll get some adjustable caster arms to start with, but I'll do that after I finish this compression test.

[Dose Pipe Sutututu]

hardrace ones aren't too bad.. I'm using them now.. I have 8 degrees of castor dialled into my R33 boat, I wanted to go more but the guy doing my wheel alignment said I'll destroy my ball joints and upper control arm bushes at lightening speeds.

[No Crust Racing]

I was looking at the ISC ones, as he's always very helpful.

Might be worth me pressing in some new ball joints also.