divil

My 951 is the only 944 I have ever driven, and I am trying to find out if this behavior is normal: the steering tends to follow the camber of the road much more than any other car I've ever driven. So where the surface of the road slopes one way or the other, I feel the steering wheel pulling to the side with a lot of force. On roads that have a good surface, it feels good, but on really uneven roads it can be pretty scary.

Technically it makes sense to me because the power assist is much less than on most modern cars, so it stands to reason that the road influences the steering wheel more. But it really doesn't inspire confidence when driving at speed.

I know it's impossible to explain exactly what it's like here, but does it sound normal, or does it sound like something is wrong?

lee101315

Check the following for play:
Ball joints
Wheel bearings
Tie rod ends

Also, if someone maxed out the camber, it would tend to do that as well.

alex

One more thing to check... I had similar characteristics when my intermediate steering shaft was binding after a manual steering swap. Greased up the u-joints and it was much better.

Ben951S

It shouldn't be a scary experience. In NJ, when coming to stop at stop lights that have high wash-boarding (waves/ruts in the road), it can actually pull the wheel strongly in one direction or another... But driving along normally shouldn't be a fight (often). =)

divil

Yeah that's exactly what I mean...it is most pronounced at traffic lights where you have those waves in the road. But it's still there, to a lesser extent, at speed. I would have simply put it down to the fact that it was a poor road surface and probably shouldn't be driven on fast, but my friends were leaving me in the dust in their 993s When I asked them later they said their cars don't really do that much.

Any time I have the wheels in the air I try to check for loose movement etc. but I never find anything. Anyway I wouldn't have thought that looseness in the steering or ball joints could influence the steering wheel though could it?

Tedro951

I'm having deja vu..

Until a good alignment, I felt the same way. The only 951/44 I've driven, so I thought it was just "quick" handling....

brad@tirerack.com

Do you have directional tires on it? They could be the problem. Notice how most top-shelf tires nowadays are asymetric?

Yeah, there's a reason for that.

Lightningmcnulty

+1 on the alignment, thats the first thing I would have checked, I believe if the car has a lot of toe out on the front it will tend to tramline more, Maybe someone can confirm this?

flashx

My Turbo does the same thing. I try not to go under 90 thats seems to help

xsboost90

had my turbo do that when....

i had alot of camber
i had directional tires/runflats
and i had a big difference in width between front/rear

MAGK944

Explains a lot, I once bought a set of wheels with tires that we're both asymetric AND directional on a staggered set-up. Terrible tramlining!

Good alignment first and if that isn't the issue change your tires to asymetric or symmetric and not directional. Going square set-up also helps in our cars. Height, castor, camber will all have an effect but easily set with a good alignment.

divil

so I finally got around to checking and they are directional - at least, they have an arrow on the side indicating the direction of rotation...I presume that means they are directional tires? I had never heard of any of this before so I will have to read up on what directional, symetric and asymmetric tires are.

So why are directional tires bad?

dillon410021

camber did it for me

odurandina

tramlining is a common issue with the 944 and 968.

Jeremy Clarkson even mentioned it in his 1992 review of the 968

(undoubtably after being tipped off by Tiff Needell).


.

MAGK944

Symmetrical tires have the same pattern throughout the width of the tire or one side of the tire looks the same as the opposite side. Advantages: wheels can be rotated L-R and also F-R if using a square set-up. Disadvantages: no extra allowance for grip on cornering.

Asymmetrical have a different pattern on one side compared to the other. Advantages: pattern on outer edge is designed for cornering, pattern on center and inner edge designed for straight line wet grip. Disadvantages: not many, but they have to be mounted on the wheels with the "corner grip" side out.

Directional can either be symmetrical or asymmetrical but can only be mounted in one direction (arrow on sidewall). Advantages: thread design is optimized to move surface water quicker. Disadvantages: no tire rotation possible unless tires are remounted on wheels. Thread pattern (which is normally "V" shaped) tends to follow pavement grooves.

Directional tires are not actually bad, it's just our cars don't get along with them too well. Reasons:
1. Our cars use small wheels (15in/16in) and they tend to exaggerate the tendency of directional wheels to tramline.
2. If we fit bigger wheels (17in/18in) and wider tires, chances are we are running higher camber and castor and this alignment has an exaggerated effect on tramlining with directional tires.
3. Finally, some of our cars ran staggered wheels, Fuchs for example. This also produces an exagerated tramlining effect with directional tires.

Solution:
1. Run asymmetrical non-directional tires. You get good corner grip and stable wet or dry straight ahead stability.
a. Run a square asymmetrical set-up if you still want the ability to rotate your tires R-L F-R.
b.Run a staggered set-up with asymmetrical tires if you just want R-L rotation on each axle.

Hope that helps, GL