Oversteer in my EK1 - thoughts?

[Alvis]

Hi guys,

With a bit of spirited driving on the weekend, I put my EK1 into a fairly decent bend and wanted to get your thoughts on the oversteer I experienced.

SITUATION:
Coming from 60km/h, braking before the corner with a blip change from 3rd to 2nd on entry (4,500+rpm), I accelerated hard through the left-hand corner. As I was probably half way through the corner I felt the rear end come loose quickly moving to the right and starting to try to overtake the front wheels.

While the front tyres weren't squealing for grip (there was a little bit of 'slip'), the car started to point left (ie the right rear was coming around), I kept the power down and with some opposite turn to the right, it straightened out.

CONDITIONS:
Dry and sunny, 19 degrees or so

CHASSIS SETUP:
Michelin Pilot Preceda II tyres (60% tread, F/R 36/32 psi). Normally have fronts at 40psi.
195/50/15 (EM1 rims)
Spoon Sports progressive lowering springs
Stock EK1 shocks (63,500kms)
Stock EK1 front sway bar
Mugen front tower bar
Stock D16Y4 with exhaust/ air intake


MY QUESTIONS:
Do you guys have any thoughts on the oversteer and how I can get the car to handle more true through the corners?

Did I do the right corrections to straighten it out?

Other thoughts:
(i) The car had been on a 2 hour rest from my previous drive that morning and the tyres had only driven 2kms since then when I put it through this corner. Were the tyres still too cold?

(ii) Did I just go into the corner too hard?

[mugen_ctr]

Rear sway bar asap! Will make the most improvement for ur car

Ive been in similar situations like what u been when i first got my car, but rather than put the pedal to the metal, i braked, instincts kicked in lol.....

few things to bear in mind..... Your suspension setup setup needs rear swaybar to keep the handling more predictable, having just springs an shockers dont cut it on the real world

Slowly learn the limits of ur car, if ur gonna do spirited driving every now and than, best to take it easy and slow, once u feel confident and feel how the car handles, u will know when the limits are, and learn how to take corners properly lol, on the track an off (PS: NOT ENCOURAGING ILLEGAL ROAD ACTIVITY)

and than find out what needs to be done to improve the driving, thats how ive done it the last 2 years, went from no rear sway bar, to 14mm, than onto a 20mm....., and now im at the point where, i see i need coil overs to improve on the handling as the springs are far to soft...... although i still have much to learn, im self learning on the way

Road tires differ greatly to track tires, they dont need to be warmed up as much, but the road conditions have the greatest impact on how well it performs

[Alvis]

Thanks mate, you always have good advice!

I thought my car might benefit from an rsb - I think I might try and locate an EK4/EM1 rsb - might be good to start with.

Would like to upgrade the shocks first, but they're probably still good to 90,000 so if I see an EK4 rsb on the market I might pick one up.

Are they 14mm or 16mm? And is there anything I should look out for when picking up a second hand one - endlinks etc?

[Lerlo]

Rear sway bar will probably give you more oversteer.
Im suffering from mid corner oversteer on my ek as well, got worse after I put on whiteline 23mm rear sway bar.
Try pushing it in the wet and see if its worse, be careful though.
I would suggest going for an alignment and checking your rear toe angle, if all else fails, tyre pressure makes hell of a difference.

[sebtoombs]

I have stock ek4 rear sway bar if you want it. Can have it for free, you would just have to cover postage from tassie. Let me know if you want it. Dunno if its any better than what you've got.

[Alvis]

Rear sway bar will probably give you more oversteer.
Im suffering from mid corner oversteer on my ek as well, got worse after I put on whiteline 23mm rear sway bar.
Try pushing it in the wet and see if its worse, be careful though.
I would suggest going for an alignment and checking your rear toe angle, if all else fails, tyre pressure makes hell of a difference.

Thanks for your feedback and yep, that's why I don't want to go too thick at this stage - pretty much whatever you increase the thickness of your rsb by, you times it to the power of 4 over your previous size to see exactly how much effect it has - so basically little increases in rsb thickness make a big difference in the way the car handles.

I would interested to try the EK4 rsb, but it might also mean I need to upgrade the fsb as well.

Do I need a subframe brace with a stock EK4 rsb on an EK1? It is better to be safe than sorry?

I have stock ek4 rear sway bar if you want it. Can have it for free, you would just have to cover postage from tassie. Let me know if you want it. Dunno if its any better than what you've got.

Thanks mate - wow, sounds good PM sent.

[trism]

Guys recommending adding a rear sway bar should reconsider posting without knowing what they're on about.

A stiff rsb is the leading cause of over steer. What I'd be doing is stiffening the front up. Alternatively, don't bother. It could've been a bad corner. If its the first time its happened, don't act straight away, see if it happens again.

Sent from my custard cannon like Peter North.

[trism]

Also, I reckon it's a simple answer. Option b, you just went in too hard. A fwd will almost never under steer while acceleration. The most common is lift off over steer

Sent from my custard cannon like Peter North.

[Alvis]

Guys recommending adding a rear sway bar should reconsider posting without knowing what they're on about.

A stiff rsb is the leading cause of over steer. What I'd be doing is stiffening the front up. Alternatively, don't bother. It could've been a bad corner. If its the first time its happened, don't act straight away, see if it happens again.

Also, I reckon it's a simple answer. Option b, you just went in too hard. A fwd will almost never under steer while acceleration. The most common is lift off over steer.

Yep, very true you have to be careful how thick you go because the changes can be quite dramatic, and if you really push it, even dangerous if you don't know what you're doing.

And yes, it is the first time it's really happened - I have pushed it before but more into a sweeping corner, rather than this one which was more tighter in the way it came around, so I agree I could have been a combination of too much speed going into the corner, tyres not quite up to temp, and the psi was down a little from the 40 I normally have them at.

What are your thoughts on stiffening up the front - do you mean a thicker fsb (I already have the front tower bar)?

As I posted before, I would really like to test it with Spoon/Koni shocks fitted before going to a rsb.

Note: I have also had my bushes checked by Pedders and they are all fine, little crack/wear on the rear trailing arms bushes, but still ok.

[mugen_ctr]

Thicker fsw? i hear? disagree here..... unless you have been through none rear sway bar to adding one, i will contest strongly about not having one! the ek4 swaybar will improve things heaps here. In theroy yes, it will add over steer, but they are wrong! coming from experience, i think u do need a rsb

The only alternative to thicker fsw is ek4/em1/ek9, which is a 26mm, than having no rsb, is just pure understeer, as the rears will be all over the place, in short, the fronts are planted while the rear end will feel loose as a goose. U need both to make the handling work a treat. I know for fact some guys in the state take off rsb for gymkhana, but that stuff is totally different to taking the car on the road.

Dont resort to springs/shocks to keep the tires on the ground, use swaybars as well, they are there for a reason

[Alvis]

Thicker fsw? i hear? disagree here..... unless you have been through none rear sway bar to adding one, i will contest strongly about not having one! the ek4 swaybar will improve things heaps here. In theroy yes, it will add over steer, but they are wrong! coming from experience, i think u do need a rsb

The only alternative to thicker fsw is ek4/em1/ek9, which is a 26mm, than having no rsb, is just pure understeer, as the rears will be all over the place, in short, the fronts are planted while the rear end will feel loose as a goose. U need both to make the handling work a treat. I know for fact some guys in the state take off rsb for gymkhana, but that stuff is totally different to taking the car on the road.

Dont resort to springs/shocks to keep the tires on the ground, use swaybars as well, they are there for a reason

I think the key point is you really need to be careful as to the thickness you go for. You need to think carefully about your current setup and what future plans you have for the car, as this will ultimately determine how your car will handle. I have no doubt the EM1/EK4 setup works for a reason, and given the power output difference to an EK1 it will be more than enough.

2 QUESTIONS:

1. If I added an EK4 rsb (still undecided) do I need an ASR subframe brace?

2. Would it then make sense to upgrade to an EK4 fsb to balance it out? (otherwise I could be making the oversteer worse with the EK1 22mm fsb)

[trism]

1. No. It worked without one on the ek4, its got the same chassis as the ek1.

2. Yes you should.

How ever i think what we need to consider is this: you pushed harder than normal, on a corner you've never driven, on cold tyres. It's not a matter of needing to upgrade suspension components, its simply that you pushed the car past the limits of the tyres.

Sent from my custard cannon like Peter North.