car handles like crap

[Speedy]

Hello guys,


i have a mysterious problem.When i drive over rough and bumpy streets or over ruts on the freeway.The car roams from left to right the car is really forced into this wandering, there are really hard forces in the steering wheel i hardly cant stop the car from roaming sideways and hard braking over bumps or uneveness is a horror when i drive in "straight" line i'm "always" steering I have PU bushes, lowered the car
and the toe is correct too.Ok i must say, on the right side the tierod has little play aswell as the upper suspension bearings.But can this cause so much roaming.

When i drive on a flat and good surface the car runs exactly straight and the steering is really precise but on uneven surface with moulds bumps etc it drives like it will follow the bumps.....I hope you understand my problem

No fun to drive anymore, it feels really dangerous especially at high speeds.

[Ivan141]

I think you're having trouble with bumpsteer. How much is the car lowered? The lowering affects the suspension geometry, causing this kind of crap to happen. RCA's might be a solution to your problem.

[20vWill]

Depending on how much lower you are, you may need to get an adjustable Panhard rod to re-centre the rear axle.

I assume you've had a wheel alignment check/adjustment recently? If not, replace the worn components and then go and get the alignment done at a decent place (computer optical/digital are best, laser alignments are OK, mirror guages can be OK depending on who's operating it...).

[Speedy]

Its lowered between 30-40mm.I forgot to mention i have 30mm spacers at the rear.At the front i took the 25mm spacers off cause with it, it was worse driving.Could the spacers at the rear cause this?Noone else had this roaming?Where can i get these RCA's, for cheap

[rikard]

Sounds to me like you have a combination of things: Bumpsteer, rear axle off center like Will said, and some toe/camber problems caused by the worn TCA.
Get the car on the alignment beam and let them check out the alignment. They should also be able to tell you if you have any bad suspension parts/ worn bushings/rack ends/ball joints.

[Speedy]

Can any one explain to me what technicaly means, rear axle is off center.
What does it mean and produce?

Thx in advance

[Ivan141]

Because of the construction of the rear axle linkage, one of the 5 bars holding the axle in place controls the lateral movement (left-right), that bar is called the lateral or panhard rod. It has a fixed length on the ae86, which means that when you lower the car, you decrease the angle of the bar, causing the end of the bar to move to the side a bit. Think of it as the hands on a clock, normal position would be 4 o clock, when lowered it would be 3 o clock, thus sitting more to the side.
You can buy adjustable panhard rods to correct for this effect.
I dont think it matters that much at 30-40mm lowering though.
I would start out with replacing worn components and an alignment, then
start looking for RCA's. Maybe we can start up a group buy thing for custom made RCA's like the ones Zax has. Not this month though..I'm out of cash. RCA's dont change the alignment of the car (as long as theyre not the negative camber type ones) so you wont be wasting money doing an alignment after you freshen up you suspension.

[20vWill]

Speedy Wrote:Its lowered between 30-40mm.I forgot to mention i have 30mm spacers at the rear.At the front i took the 25mm spacers off cause with it, it was worse driving.Could the spacers at the rear cause this?Noone else had this roaming?Where can i get these RCA's, for cheap

You can get away without an adjusted panhard rod up to about 35mm from stock. Any lower and the axle will be significantly off centre, enough to cause wandering off line when throttle is applied and released.

As for the spacer issue.... Errr what is going on with these? Are you running adaptors to use FWD offset wheels on your car or something? If you are running 30mm spacers in the rear and none up front with the same wheel offset front and rear, you are going to have serious handling issues!! The overall offset of the front and rear wheels should place the centreline of the rears through the centreline of the fronts.

If you bin the spacers and put stock wheels back on, I think you may have found a major contributing factor to your dog-like handling.

Tell me the size and offset of your front and rear wheels and I can have a guess at how wrong/right they are.

[Speedy]

Quote:Tell me the size and offset of your front and rear wheels and I can have a guess at how wrong/right they are.

Errrm, I'm in school right now.But I think it was 25 offset they are Atiwe 15x7.But I'm not sure at the moment.

[NoHachi]

20VWill, I'm not totally understanding the spacer issues? I know of quite some cars running different offsets front to back. What are the specific issues this causes?

The other remarks made in this thread are spot on. You are noticing the effects of bumpsteer. Probably the whole allignment of the car has changed while lowering so that just makes the problem worse.