Wet weather handling

[tomwinton]

All

My 993 Targa has had new springs and shocks, new wishbones, and very recently a full geometry alignment at my local OPC. Currently on Pirelli P Zeros, all with good tread depth left.

In the dry it handles fine, but in the wet it's like its on margerine, not rubber. The steering goes all woolly, it twitches in and out of the lorry tramlines on the motorway inside lane, and it totally fails to inspire any sort of confidence... I find myself being overtaken by the flat cap Almera brigade out on their Sunday drive along the M4!

Is this normal?? Am I just being "chicken" - or is there something I can do to improve the way my car handles in the wet?

Ta

TOm

 

[mmylonas]

I had an identical problem when I bought mine a few years ago and it was fixed by a 4 wheel alignment at Tognola's in Datchet. If you've already had that done by an OPC not sure where to suggest although the symptoms sound suspiciously similar to the non-alignment ones. I think (from reading other posts in a similar vein) that a printout should be available of the settings after the OPC session. Might be worthwhile sending those to Tognola and asking if they seem right. Or as a first port of call asking the OPC to redo the alignment?

Michael

 

[Mark Elder]

Not sure about the Targa (but can't see how wet can make any difference), but with the coupe it feels exactly same in wet as the dry, except obviously it will break away a lot sooner. ie when it has good contact with the road the feel will be the same in wet and dry.

Mine will get out of control if you accelerate very hard on bends on winding A roads in the wet (but even then you just back off the power and it lines itself back up nicely). On a motoway, at UK speeds, I don't believe you should see a difference.

As above, I'd suggest it's the alignment (you took it to an OPC?, what would they know about a 993?[&:])

 

[metric_thumbs]

What happens when you drive it on a flat surface and take you hands of the wheel?
Also take a look at the car from all sides and see if it is dead level in all axis's

 

[fergusond]

Hi Tom, what type of P Zero do you have, I had horrendous experience with rear 18" asimmetrico in the wet, they were death traps so I dumped them. I use my car all year round and when it gets cold I have to reduce the pressures, mainly in the back, what pressures are you running.

David

 

[Stewart Rix]

18" rims? Quite a few members seem to talk about tramlining badly on motorways on the bigger wheels. Certainly don't have that issue (on the M4), but then I'm on 17"s. You could always stay out of the inside lane......

 

[tomwinton]

Don't recall what P Zeros I've got (will have a look tonight) - but being a Targa, they're only 17"s

 

[day1zero]

18's do seem to tramline....I do many a mile up and down the M4...the inside line is a mare at times...the wet does seem to make this worse....

I have coniti sp2...they brilliant in dry....and pretty good in the wet....I had the alignment done at Tognola (to RS settings). There was a definate change in handling (noticeable). Turn in was much sharper and just felt more confident.

If you need to see my settings I am happy to pass them on.

 

[angry]

Wouldnt touch 18" rims on a 993....awfull.
Had no probs with p-zeros in the wet,really good,but as soon as the tread gets to the wear bars, get them changed...they are bad then.
You really have to watch who does your geometry,very few people have a real clue and even fewer people have thier machines calibrated at the specified intervals.As ive said in the past i use a guy who uses a level floor and manual equipment(the same used to set up alignment machines!)and my car was transformed having been previously set up on a digital/laser sophisticated machine.
Dan

 

[clubsport]

ORIGINAL: angry

Wouldnt touch 18" rims on a 993....awfull.

Huh?...care to explain why?...keen to learn, some of us unfortunates had them fitted from the factory and had little choice in the matter...

 

[911addict]

I didn't get on with my Pzero Asimetricos in the wet. The newer Rossos are much better. I'm still on 17's.

 

[tomwinton]

Ok, David - Tyres are Pirelli P Zero Rossos on 17"s

 

[angry]

ORIGINAL: clubsport

ORIGINAL: angry

Wouldnt touch 18" rims on a 993....awfull.

Huh?...care to explain why?...keen to learn, some of us unfortunates had them fitted from the factory and had little choice in the matter...

The cars that i have driven,that were on 16s or 17s as standard,drive and handled a lot better than when we fitted 18s to them.Those that come with 18s as standard,should have a few geometry tweaks.(opcs should have done this)
Personally i fell you get much more feedback and predictability with 17s.
But if you are out for a Sunday afternoon pose all you will notice is the Tramlining,with the 18s.
Dan

 

[38F3E1]

In someways I agree with this. Having been a long term driver on 17" wheels they all seem to drive nicely and setup doesn't seem so critical. As soon as you go to 18" wheels, as I did, the setup of the car and the alignment seem to become critial. A badly setup one is really awful.

However it is possible to get a car on 18" wheels set up well and then they are very nice as well so don't all give up hope.

Ian.

 

[clubsport]

ORIGINAL: angry

ORIGINAL: clubsport

ORIGINAL: angry

Wouldnt touch 18" rims on a 993....awfull.

Huh?...care to explain why?...keen to learn, some of us unfortunates had them fitted from the factory and had little choice in the matter...

The cars that i have driven,that were on 16s or 17s as standard,drive and handled a lot better than when we fitted 18s to them.Those that come with 18s as standard,should have a few geometry tweaks.(opcs should have done this)
Personally i fell you get much more feedback and predictability with 17s.
But if you are out for a Sunday afternoon pose all you will notice is the Tramlining,with the 18s.
Dan

It sounds like you have created your own problem with fitting 18"s and not allowing for complementing them with suspension and geo......there is more mechanical grip available with the 18"s, Porsche didn't fit them on 993 RS & cup cars just to pose

 

[LeoSayer]

I've got a set of 18" wheels (with Contis) and another set of 16" wheels (with Bridgetstone S02) for my 993 and I can honestly say there is very little difference between them.

The steering is heavier on the 18s, probably because of wider front tyres and the ride over bumpy b-roads is more pleasant on the 16s but the difference isn't night and day like some people would have you believe.

As far as wet weather goes, on both sets of wheels there is no difference apart from a lower level of grip when cornering/braking/accelerating hard. If the tyres are in good condition then the alignment has to be the first thing to look at.

 

[pike]

I had similar issue with tramlining on motorways and generally scary handling when I first got my car. A 4-wheel alignment sorted out the handling. Some of the settings were completely wrong. I was using Pirelli P Zero Assimetricos at the time - so Iwoudn't have thought it is the tyres causing the trouble. I have subsequently moved to Michelin Pilot Sports as the Pirellis only lasted about 5k miles.

 

[tomwinton]

Dayzero - I'd be interested to see your settings.

I dug out my printout, and they appear to be the standard setup settings... anyway, car is back at the OPC tonight, so I'll see what they say in a day or so.

Ta

TOm

 

[delta]

My vote is for 17" as they give a more progressive feel when nearing the limit than 18" which in turn means more fun can be had. Lets be honest which gives you the biggest high ,going round a corner 0.001 sec faster or just sliding about abit[]