993 wheel alignment - how often?

[nel]

After fitting a PSS9 suspension kit to my 993tt, I had the wheel alignment and corner weights done. The car was great to drive afterwards, tracking straight and true even over bumps and dodgy road surfaces.

Now a couple of months and 2000 kms later it feels like it already needs aligning again - when the back wheels are on different surfaces, e.g. one wheel on tarmac the other on a drain cover she squirms sideways a bit.

Maybe a Vmax day didn't help, but are you chaps experiencing the same requirement for frequent realignment or is it just me? Is it worse for 4WD versions than 2WD? Shouldn't be as it feels like it's the back wheel alignment that's screwed up again on my car, but maybe the turbo power to put down doesn't help.

[MOD500]

I think once a year is ok for road only driving?

I had mine realigned after two Brunters days, and the back was said to have been slightly out. Though I believe only slight errors can cause big differences when driving.

Hopefully someone with more knowledge will chip in!

[silver993tt]

Had mine done about 5000 miles ago (8000kms), still ok.

[aceparts_com]

I had my car setup when I first got it and have done quite a few hard track days since it's still pretty much perfect and very well balanced.
Get it on the track for a check up or try a day with Don; it might be the nut behind the wheel that's lose!

I do find that tyre pressures affect the overall feel of the car and now swear by factory pressures.

I have adjusted the tracking about 10 times in the last month thought in an attempt to get the steering wheel & car straight. Ive now given up as slight camber imperfections in the road seem to send it off from my planned path although I put this down to a combination of crap roads and wide tyres (i've given up!)

How do you find the Pss9 kit? I've been contemplating it for a while now but have trouble staying in the seat as it is. I think RS seats first.

[nel]

aceparts_com said:

How do you find the Pss9 kit? I've been contemplating it for a while now but have trouble staying in the seat as it is. I think RS seats first.

When I decided to go for the PSS9 kit I was planning on doing a few track days a year. Since then I'm reconsidering whether it's worth taking a luxury, fully-loaded road porker weighing in at over a tonne and a half onto the track, and prefer the idea of buying a stripped out, cage-equipped 964 to go and play with, shared with a like-minded, Porsche owning friend (who is currently building a palace with a fortuitously large garage!).

So I don't know whether I've wasted my time going for the PSS9 kit as I'll maybe never bother using the adjustable dampers other than on their softest (maybe least hard would be more precise!) road setting. Also, even with the springs set up on the highest ride height possible with the PSS9 kit, the ride height is very low (i.e. RS height of around 125 mm front, 110 mm rear at Porsche reference points). This doesn't bother me as previously I had the low-riding MOO3 setup (without chain steering wheel ), but if ground clearance is an issue coz of a steep drive or speed bumps then be warned!

However, the benefits are very clear. The car sticks like glue and no longer wallows over humps and bumps. There were a couple of places where braking at the end of the straight was hairy as the car wallowed and porpoised about when I was trying to scrub off criminal amounts of speed before the twisties - these are now handled with aplomb and the whole set-up feels much more secure. But the reduced wallowing would almost certainly have resulted from just changing the shockers - changing the springs was maybe over the top! The ride is firm, but not uncomfortably so - you soon make a mental hole map on the roads you use regularly to avoid the worst of them.

After all that, I'd go for the PSS9 kit if you are going to do trackdays, want to lower the car, or need no compromise handling. Other than that, the cheaper option of the H&M kit or just changing the shockers will probably do the trick.

Nose back to the grindstone....

Niels

[Buster44]

nel said:

After fitting a PSS9 suspension kit to my 993tt, I had the wheel alignment and corner weights done. The car was great to drive afterwards, tracking straight and true even over bumps and dodgy road surfaces. Now a couple of months and 2000 kms later it feels like it already needs aligning again - when the back wheels are on different surfaces, e.g. one wheel on tarmac the other on a drain cover she squirms sideways a bit.

Could it just be the differing levels of grip between the two surfaces causing the sideways squirm??

[nel]

Buster44 said:

nel said: After fitting a PSS9 suspension kit to my 993tt, I had the wheel alignment and corner weights done. The car was great to drive afterwards, tracking straight and true even over bumps and dodgy road surfaces. Now a couple of months and 2000 kms later it feels like it already needs aligning again - when the back wheels are on different surfaces, e.g. one wheel on tarmac the other on a drain cover she squirms sideways a bit. Could it just be the differing levels of grip between the two surfaces causing the sideways squirm??

No doubt there's an element of that Buster, but she definitely tracked truer even over differing surfaces just after the alignment. Suppose I'll get it looked at when the car is next in the garage and ask them to check whether anything's moved and correct if necessary.