vash

Hi i have a 98 UK IMPREZA Tubro 2000
I have put on some quite smart 17" Rims and had it lowered 25mm On some highquality springs ( well the ones that Regal AutoSport In Southampton Recommended )
Anyway recently im getting huge understeer and general loss of traction, i have checked the tires and they have plenty of tread on them and the camber looks ok !
Any Ideas what is causing it and how i can fix it??

nigelward

Was the suspension geometry on the car adjusted after the springs had been fitted.

If it was done properly, using laser alignment, you should get a data sheet showing what geometry settings the car has been setup with.

If it has not be done then get it done as soon as possible otherwise the car won't handle properly and you may end up with uneven tyre wear (among other things).

Nigel

dowser

Unsuitable match of springs and dampers seems likely....

Richard

ex-webby

good replies so far... I would say it is one of the following...

- Damper / Spring match (as suggested)

- Geometry (as suggested)

- potentialy more body roll caused by lowering

- potentially higher load transfer during transitions due to increased roll rates (higher roll resistance due to springs and tyres)

- you could be feeling the difference between the sensitivity needed for lower profile tyres (which are less forgiving than high profile)

All the best

Simon

Claudius

The standard suspension is a comfortable compromise for road use. If you change the springs to shorter ones, you need to know exactly what rate and progressivity (if at all) you need. Just using shorter or softer springs will make the car lower but not better and roll will increase.

Another possibility of you having understeer is the geometry, particularly camber and toe. If the shop were you bought the parts set up your geometry according to standard Subaru specifications, you will get understeer. Dont toe in the front, and dont toe in the rear too much (or toe it out )

Also, did you get the wheels and the springs on the same day? What make model and size wheels did you buy? (perhaps you increased unsprung weight).

Hope you get it sorted soon

ex-webby

Hi Claudius

Why do you say not to toe in the front or rears? or to toe out the rears?

All the best

Simon

kerm

What tyres have you got fitted, some tyres are made for 4x4 and some are not.......
It could be a loss of traction with the road????????

Claudius

If you toe in the front, you will get more understeer. That's why I recommend a neutral setting, or a more neutral setting. Depends on driver preference, some like it 0, some like a slight toe out (-1 or -2). I like a slight toe out.

If you toe out the rear, you get serious oversteer which compensates for the understeer tendency. As the original poster had an understeer problem, if you induce oversteer in the back, you will reduce the understeer tendency.

I wouldnt recommend a toe out in the back for anybody who doesnt really know how to drive ie weight transfer, braking (without ABS) and drifting because it may make you end up off the road with a damaged car...

But if the rear is toed in, you can still slightly reduce the toe in.

ex-webby

Hi Claudius...

unfortunately it's not as simple as that... Very few things in vehicle dynamics let alone chassis dynamics are definites.. for instance...

Front toe in does not necessarily mean more understeer, in-fact it can mean the opposite. Toe out (+ve toe) can be used to reduce stage 1 turn-in understeer, which is the tiny part of the entire dynamics that many people pick up on to say that toe-out reduces understeer, and therefore toe-in increases understeer.

In addition, there is a difference between static toe and dynamic toe on just about all cars. Firstly there is the fabled bump steer to consider (which is the reason why adding some front toe-in to scoobies can REDUCE turn-in understeer as under bump the front comes back closer to zero toe / slight +ve toe). In addition to this the suspension components flex creating dynamic toe out under braking and to a lesser degree dynamic toe in of the driven wheels under acceleration.

All the best

Simon

Claudius

I'm just saying what I've experienced when changing the toe settings.

I cant see what I should conclude from your post. What about the person who needs geometry setup advice? You confused me here.