[Turninconcepts.com]

I'll start, and I'm wondering how long until someone calls me an idiot on this.

2008 STi.
Rear camber.

Run 0 degrees or even just a little bit of positive camber depending upon stiffness of springs or rear bar.

Now, before you call me an idiot, think. Just think. Why oh why would I be saying this? It certainly isn't to start a flamefest.

[twigg107]

interesting..... Doesnt the wishbone suspension increase negative camber as more load is put on it?

[paikman]

I'm assuming you guys have been getting better traction when off-camber midway or exiting a turn like this?

[Turninconcepts.com]

Originally Posted by twigg107

interesting..... Doesnt the wishbone suspension increase negative camber as more load is put on it?

bingo. Yes it does. Tom@Kartboy, Tony and I have been discussing this at some length. Tom was able to take some measurements the other day when he had some free time.

Starting from full droop - for each 1/2" of compression negative camber increased by .2*.

In other words, as you load the tire more you roll more into negative camber. If you don't "bank" some camber to begin with you then lose quite a bit of contact patch width when you load the tire reducing lateral grip.

Now, for those of you who like a loose car or love to throttle steer, then this can be a very good thing, but you have to be good. Us mere mortals can become quickly overwhelmed with trying to keep up.

Now comes the tricky part - the rear bar.

Lets say we set camber at 0. Nice easy baseline to think from.

You go for a spin on the stock bar, get compression roll the tire over.

Then you go for a spin on a new rear bar. Get compression, BUT not as much, but the tire rolls over.

This theory would dictate that a rear bar increases rear grip, BUT we all know that a rear bar usually induces more oversteer. So now the question is - what really happens. We're going to do some more research, and find out, but we'd like some thoughts from others.

[polyol]

Just lose the rear sway and go with 600lb rear springs

[Turninconcepts.com]

Originally Posted by polyol

Just lose the rear sway and go with 600lb rear springs

Oh sure. Really jack up the SOFC (significant other factor of complaint). That'll go over well....

Oh, and 600lbs in the rear isn't going to have AS drastic an effect on the 08 as it did on the GD chassis. Motion ration in the rear is a bit different.

[Digitalfiend]

This could be an interesting thread. Let's keep the filler posts to a minimum please (I've removed some posts already).

[1day]

Ok, now how do we adjust it? You got something new in the works?

[twigg107]

Originally Posted by 1day

Ok, now how do we adjust it? You got something new in the works?

any tire place that does alignments can adjust it.

[1day]

Originally Posted by twigg107

any tire place that does alignments can adjust it.

The rear camber is "fixed" from the factory= Non-adjustable.

[MEXSTIMPREZA]

We can all blame Peter Solberg for this (he wanted less polar inertia in his next WRC car, and that´s exactly what he got with the hatch). But, IMO, we should be looking more to the front of the car if we want a more neutral handling car, again IMHO.

[4banger]

Originally Posted by Turninconcepts.com

Then you go for a spin on a new rear bar. Get compression, BUT not as much, but the tire rolls over.

This theory would dictate that a rear bar increases rear grip, BUT we all know that a rear bar usually induces more oversteer. So now the question is - what really happens. We're going to do some more research, and find out, but we'd like some thoughts from others.

This is my take - After you put the stiffer rear bar on, there is more weight transfer between the two rear wheels. One wheel is loosing grip faster than the other wheel that is gaining grip. Take a look at the graph of lateral grip vs verticle load in Stretch's spreadsheet and double check my thoughts.

[RallySportDirect]

Good thread

Just some background from I gathered from doing some track time our 2008 STi.

The rear suspension can benefit ALLOT on the new 2008 Sti with some camber adjustment.
Going hot into a corner, the front end will bite hard (with lots of camber), but the back almost does not want to follow the front. As the suspension compresses its noticeable that the back gets more and more grip as the camber is increased during compression of the rear suspension.
If you look closely, you will notice that the rear camber is still relatively close to 0.



Also Looking at the tires after the track event. It was noticeable that the rears suspension was not allowing the use for the full tire. As the outside of the tire had more wear then the inside.

[Turninconcepts.com]

Originally Posted by RallySportDirect

Good thread

Just some background from I gathered from doing some track time our 2008 STi.

The rear suspension can benefit ALLOT on the new 2008 Sti with some camber adjustment.
Going hot into a corner, the front end will bite hard (with lots of camber), but the back almost does not want to follow the front. As the suspension compresses its noticeable that the back gets more and more grip as the camber is increased during compression of the rear suspension.
If you look closely, you will notice that the rear camber is still relatively close to 0.



Also Looking at the tires after the track event. It was noticeable that the rears suspension was not allowing the use for the full tire. As the outside of the tire had more wear then the inside.

I've noticed that in street dirving and autox. Have the first track day scheduled next Monday to try it out. Interested to see the results. Definitely going to need some adjustability back there.

I am all for adjusting front camber in an attempt to neutralize the handling of the car, but there is only so much you can do with the front to accomplish this. Remember, as you add more camber in the front you really start to severely affect brake and straight line stability not to mention tire wear for daily driving.

Tony