How To Know If The Car Is Actually Oversteering?

[SS8_Gohan]

Hi all,

so it's been a few months since i've had SK's bilstein/whiteline shocks/springs in the car, along with camber kits (set to Sk's specs) and adjustable swaybars.

Swaybars came first, and the difference was quite noticable. Initially set full hard rear, and full soft front, sat a lot flatter, but always wondered if it was set a little too tail happy....

Springs/shocks came after and car sat flatter again, felt alot more solid and planted on the road, but i had the swaybars put back to the middle settings before a track day (both front/back bars) as i thought i'd try for a more neutral setting.

The question is, how can you tell if you have too much oversteer? I could get the TCS light to come on fairly easily out of a corner at Sandown, and i don't really have major power mods either.

So how do i know if it's just the tyres losing grip, just too much power being put down, or that i have too much oversteer?

I'm not really knowledgeable enough in terms of feeling what the car is doing as the 34 is my 2nd car, and my 1st performance car.

I also think that the car still has quite a bit too much body roll, even with the SK spring/shocks AND adjustable swaybars. Would it be silly to set both front/rear to the hardest setting?

Is there anything else that can be installed to reduce body roll?

cheers,

daniel

[djr81]

Technically you have oversteer if the slip angle of the rear tyres is greater than tht of the front. An explanation which I imagine is about as helpful as a poke in the eye.

Some questions for you which will make it easier for others:

Does the car have an aftermarket diff or a stocker LSD or otherwise?

How does the car behave when you aren't on the throttle?

Do you have some photos of the car cornering?

Traditionally on corner exit you feed as much throttle into the car as you can without making it oversteer too much. The more gentle you are the better it works. Low powered cars tend to be set up so they oversteer more easilly than higher powered cars. It is quicker that way.

Tyres only have so much grip. Look for friction circle on the internet. Whatever grip is being used for turning cannot be used for accelerating. So you need to trade turning performance (ie cornering or generating more oversteer) with traction (ie accelerating down the straight). Broadly that is. Weight transfer tends to make a bit of a mockery of the assumptions....

[blind_elk]

Isn't the simple answer :

You have oversteer BECAUSE you have lost traction (in the rear)?

[djr81]

Err, no. You can have oversteer without breaking traction. Just as you get understeer without breaking traction.

Ofcourse you get it when you lose traction aswell - either locking rear brakes or with wheelspin.

[Medium Dave]

I would suggest working on your corner entry, concerntrate on balancing the car and making it as smooth as possible, e.i, get your gear changes done before the corner, ease off the brakes onto the throttle, and turning the car in nice and smooth, then dont apply power till you know you dont have to take it off.

Leave your suspension on the middle settings, a lot of body roll & traction problems can be rectified with the device behind the steering wheel - Sorry, I dont mean to sound harsh, but the best thing I have ever done was to have someone who was an awesome driver teach me how I went from thinking I was a good driver, to realising I dont know anywhere near enough!

Edited May 13, 2008 by Medium Dave

[Sydneykid]

Hi all,

so it's been a few months since i've had SK's bilstein/whiteline shocks/springs in the car, along with camber kits (set to Sk's specs) and adjustable swaybars.

Swaybars came first, and the difference was quite noticable. Initially set full hard rear, and full soft front, sat a lot flatter, but always wondered if it was set a little too tail happy....

Springs/shocks came after and car sat flatter again, felt alot more solid and planted on the road, but i had the swaybars put back to the middle settings before a track day (both front/back bars) as i thought i'd try for a more neutral setting.

The question is, how can you tell if you have too much oversteer? I could get the TCS light to come on fairly easily out of a corner at Sandown, and i don't really have major power mods either.

So how do i know if it's just the tyres losing grip, just too much power being put down, or that i have too much oversteer?

I'm not really knowledgeable enough in terms of feeling what the car is doing as the 34 is my 2nd car, and my 1st performance car.

I also think that the car still has quite a bit too much body roll, even with the SK spring/shocks AND adjustable swaybars. Would it be silly to set both front/rear to the hardest setting?

Is there anything else that can be installed to reduce body roll?

cheers,

daniel

Advanced driving school time Daniel.

In the interim my often published swaybar set up list

I usually start of with the front bar on full soft and the rear on the middle setting.

If it oversteers too much, then I move the front bar to the middle setting

If it still oversteers too much, then I back the rear bar off to the softest setting

If it still oversteers too much, then I move the front bar to the highest setting

If it still oversteers too much, then you might need some more rear camber and/or the HICAS is still working (get rid of it) and/or the rear subframe alignment kit needs to be set to maximum traction (squat)

I usually start of with the front bar on full soft and the rear on the middle setting.

If it understeers too much, then I move the rear bar to the highest setting

If it still understeers too much then you don't have enough caster/camber on the front

Cheers

gary

[SS8_Gohan]

hey Gary

i've done 2 advanced driver training days, and 1 day at track day at sandown with instructors on a few laps

when i had the swaybars installed, i was trying to remember that exact post off the top of my head when i was at the workshop, i went with full hard rear, full soft front to start with, which was obviously wrong for a setting to start out on.

But it's the "if it still oversteers..." that i don't know if it is or isn't... that's what i'm getting at, the feeling, or knowing that is what's happening. As a driver, i guess i just don't really get it. I mean, i know what it is, i know what it looks like, but being behind the wheel and feeling it seems to be a different matter for me.

I guess it's a bit like yourself being able to revalve the bilstein shocks to your specs... not everyone would be astute enough to be to engineer something like that.

I don't have the 'feeling' know-how of it it's just my right foot that is causing the TC to kick in, or if it's perhaps my suspension that is contributing to it.....

djr81: no aftermarket lsd that i know of, no pics of my car cornering that i know of. Good question re: without throttle... do you mean completely without throttle? or just whilst it's not being actively pressed?

kicking myself for not asking the instructor who drove me car, what he thought of it. He was ultra experienced, can't remember the qualifications/history but had been in/around motorsport for a long time.

Maybe i'll go do another day with instructors, let a few different ones drive the car and see what they think. Is something that perhaps a suspension specialist workshop could do? ie.... "tune" or some sorts?

oh and yes, aware of the friction circle, see it a couple times at the Driver Dynamics days....

[Roy]

You cant go wrong going to the next WRX day at Sandown. I or anyone else can jump in teh car with you. Nothing beats seat time and persoanlly i wouldnt be changing anything more on the car until you get your head around driving how it is now.

Get mroe seat time. Get familiar with what the car is doing then go back and do another driver training day to make sure you are not falling into bad habits.

Personally what i see all the time is the first few times ppl go to the track they are using the wring gear. If you want to use 2nd then slot 3rd and you can use a lot more throttle and the car settles down a lot more makign it far more stable. Confidence increases, speed increases, fun increases and tyre and engine wear decreases from pinning 2nd gear to redline all the time with wheelspin

[djr81]

hey Gary

i've done 2 advanced driver training days, and 1 day at track day at sandown with instructors on a few laps

when i had the swaybars installed, i was trying to remember that exact post off the top of my head when i was at the workshop, i went with full hard rear, full soft front to start with, which was obviously wrong for a setting to start out on.

But it's the "if it still oversteers..." that i don't know if it is or isn't... that's what i'm getting at, the feeling, or knowing that is what's happening. As a driver, i guess i just don't really get it. I mean, i know what it is, i know what it looks like, but being behind the wheel and feeling it seems to be a different matter for me.

I guess it's a bit like yourself being able to revalve the bilstein shocks to your specs... not everyone would be astute enough to be to engineer something like that.

I don't have the 'feeling' know-how of it it's just my right foot that is causing the TC to kick in, or if it's perhaps my suspension that is contributing to it.....

djr81: no aftermarket lsd that i know of, no pics of my car cornering that i know of. Good question re: without throttle... do you mean completely without throttle? or just whilst it's not being actively pressed?

kicking myself for not asking the instructor who drove me car, what he thought of it. He was ultra experienced, can't remember the qualifications/history but had been in/around motorsport for a long time.

Maybe i'll go do another day with instructors, let a few different ones drive the car and see what they think. Is something that perhaps a suspension specialist workshop could do? ie.... "tune" or some sorts?

oh and yes, aware of the friction circle, see it a couple times at the Driver Dynamics days....

Sounds like you need to do two things to further your understanding.

1: Buy a book on car handling and or driving. There is a thread somewhere on that & if you go through the titles listed & then check what they look like on Amazon. You can get most of them through the ptistop bookshop in WA if you want to sort them locally.

2. Once you understand what is happenning in a theoretical sense get an instrutor to drive the thing with you as a passenger. Either that or find some gravel roads.

In the interim it may be better to explain a cornering sequence in four parts:

1. Braking.

2. Turn in.

3. Mid corner.

4. Corner exit.

Chances are if you are getting oversteer it is on corner exit and is due to either poor traction from the lack of LSD (Single spinner bullshit in other words) or less likely too much throttle. I would doubt the car is oversteering in the first three stages of the corner.

Hope that helps.

[BHDave]

Probably a very silly question, but do you have to counter steer when it happens? If not i'd say you are just too agressive with the throttle on corner exit and the tcs is effectively modulating the throttle for you. I'd suggest if you aren't countersteering when the lights flashing at you then the car is probably neutral enough or maybe even understeering. All it's doing is preventing a bit of power over.

[Beer Baron]

my piece of advise is whilst on the track turn the TCS OFF. then you will be able to better see what the car is doing. all sorts of things will trigger TCS which cuts your power and thus gives you no chance of figuring out what was happening.

[SS8_Gohan]

sorry late reply

thanks for all the help guys.... i have a feeling it maybe just a bit too much throttle on exit, or too much too early. R34 turbo's have factory LSD's as far as i know.

i might read into it a bit more, but yeah, as some of you have said, probably the best thing is some seat time.

oh, i am guilty of the late gear change too did notice that does a nice job of unsettling the car during heavy braking

slightly OT, but if you have full adjustable sway bars, strut braces front/rear, is there anything else that can be done to reduce body roll? just out of curiosity.... i guess that leaves only a roll cage?

[Sydneykid]

sorry late reply

thanks for all the help guys.... i have a feeling it maybe just a bit too much throttle on exit, or too much too early. R34 turbo's have factory LSD's as far as i know.

i might read into it a bit more, but yeah, as some of you have said, probably the best thing is some seat time.

oh, i am guilty of the late gear change too did notice that does a nice job of unsettling the car during heavy braking

slightly OT, but if you have full adjustable sway bars, strut braces front/rear, is there anything else that can be done to reduce body roll? just out of curiosity.... i guess that leaves only a roll cage?

Why do you think it has too much roll?

Cheers

Gaery