Winter tyres f**king up handling - Page 2 - 911/Carrera GT - PistonHeads UK

Got Pirelli Soto I's on the front (tyres are one year old and fitted them for the second year running) and had New Pirelli Soto III's fitted to the rear as the Original Soto 1 rears didn't fit (changed from 991S to 991 50th and the rear wheels are a different size) Handling has gone to s t (talking at 30mph plus) - car feels like its on wet mud, no feel, cambers in the road pulling it all over the place etc. Going back to the tyre fitters tomorrow but any ideas out there ?( Checked they've been fitted right in terms of rotation direction and they're all correct, Ican't believe there's a compatibility issue between I's and III's on paper but can't think what else it could be, the Soto I's front and rear on the previous car felt fine)

How many miles have you done on the new rears? Winters always feel dreadful when new.

As Jackwood says, they can take some time to give their best. My Vredestein winters were lethal until I'd got about 4-500 miles on them.

What's the ambient temp? Today its been 12c and mine feel like I'm driving across a field of mud! When its 5c they are much better.

done about 150 miles so far I'd guess, cant remember them feeling this bad on the previous 991 though

I've only driven my BMW on winters (last 4 years) but can echo the posts above about how they feel when new or outside their ideal temp range.

its a few degrees above their ideal baseline which I believe is 7 but no way am driving on them aggressively, car and hedge would seem a likely outcome the way they are at the moment. I guess see how they behave after a week or two.

Stupid question - are they the same profile/size?

They are exactly the same size and profile as the summer Pirelli PZeros so nothing to do with speedo/wheel rotational speed computer issues

Purely a guess Have you fitted 305/30/20 sotto 3. Not N rated? Should have fitted 295/30/20 sotto 2. N0. Just because summers are bigger, doesn't mean winters will be the same size.....

I'll check sizes in the morning, surely the winter tyre should be the same size as the summer tyre though?

Almost all Porsche winter tyres are a size down on the 911 range. Your running a wide body chassis as per the 4s. A 4s has a size down, so a 50th Ann car probably will as well. I'm guessing your tyres from last year are 295/30/20. If so, put them on. I am a great believer in N rated tyres, and stick to Porsche rules...... Others on here don't, that's fine by me, I don't preach. Are your tyres N rated?

oddball1973 said: I'll check sizes in the morning, surely the winter tyre should be the same size as the summer tyre though? This suggests winter and summer 'tire' size are the same for 19 and 20" wheels: http://www.porscheownersmanuals.com/2012-911-carre... SS7

shoestring7 said: oddball1973 said: I'll check sizes in the morning, surely the winter tyre should be the same size as the summer tyre though? This suggests winter and summer 'tire' size are the same for 19 and 20" wheels: http://www.porscheownersmanuals.com/2012-911-carre... SS7 Yes Narrow body chassis do generally use same tyre sizes. 50th is a wide body, and therefore generally run a sizedown If there is an i manual for the 50th it will tell all.....

When I stick the winter wheels/tyres on my wife's BMW 1 series there is a noticeable different in lateral grip in the dry until it is 'cold' - no apparent issues in the wet. I've always put this down to the narrower profile of the winter tyres and that winter tyres are supposedly designed for temperatures under 7C.

Mad March Taffy said: When I stick the winter wheels/tyres on my wife's BMW 1 series there is a noticeable different in lateral grip in the dry until it is 'cold' - no apparent issues in the wet. I've always put this down to the narrower profile of the winter tyres and that winter tyres are supposedly designed for temperatures under 7C. Winter tyres have deeper tread so you'll also feel feel the tread blocks moving around. Similar to having proper off-road tyres on a bike. SS7

Thinking its the directional Sotto3's on the back not working with the Assymetrical Sotto1's on the front, my tyre guy is speaking to Pirelli Technical at the moment Edited by oddball1973 on Monday 22 December 15:36

problem sorted, rear directional tyres and front asymmetric f k your cars handling right up. Asymetrics front and rear and now drives fine

Pleased you got to the bottom of the problem. Mental note made not to make the same error.

Read this post with interest as I put Pirelli writers on my 997 C4S a month or so back and was surprised how useless they were initially. Ditto all the comments above they clearly also need some miles to bed in and also the correct temperatures. Glad you found your solution. Happy motoring through this bitter winter! ;-)

Read this post with interest as I put Pirelli writers on my 997 C4S a month or so back and was surprised how useless they were initially. Ditto all the comments above they clearly also need some miles to bed in and also the correct temperatures. Glad you found your solution. Happy motoring through this bitter winter! ;-)

Using nokian n0's on a c4s - just for future reference, it feels great... and the rears are a size down on the summers (295 vs 305), as per the manual

The snow has landed in the Midlands. The first thing I'll be doing in the morning is getting out in the Boxster on its winter tyres, ideally with the roof down OP - try your winter tyres now and see what you think!

Coming down in spade fulls here in Rutland, might have a little venture out..... In the wife's Evoque

oddball1973 said: Coming down in spade fulls here in Rutland, might have a little venture out..... In the wife's Evoque Come on, get those winter tyres used for what they were meant!

Sottozeros on 997.2 did excellent job on Boxing Day 320 mile round trip from Yorkshire to Luton Airport. 3 deg temp plus heavy rain and some sleet. Car felt very composed at all times and inspired confidence even through patches of standing water on motorway ...... the floaty trouser clenching feeling was very much reduced vs summers. The tyres are spray monsters too and appear to clear water very effectively, not sure cars behind were so happy about that. The sottos are quiet and ride seems comparable to the Michelin PS summer shoes. Had a little play on way home on quiet roads where safe and the handling is still fun with significant cornering speeds possible and tyres once rolling were putting boost down with no complaints. Sure the tyres feel a little squidgy when you push on hard but overall I was amazed at how the car was transformed into effective winter machine (was gonna write winter road warrior but that sounds a bit ridiculous). To any winter tyres doubters - give the tyres a whirl in the bad weather and I think you will be very surprised how effective they are. I think we have to be resigned to fact that on warmer 7+ deg ish days that the winters do not feel great but is a small sacrifice to have the cold weather capability when needed to get you home safe? Edited by MOD500 on Sunday 28th December 08:43

Well went out this morning. Firstly these cars are useless at defrosting anything more than a slither of ice on the front windscreen, I had to use a ton of de-icer and a little plastic scraper. The rear quick clear though works brilliantly, just like a Ford windscreen The Sottozeros arent much better than a regular tyre on ice although that goes without saying, but by god you can blitz through the snow and slush without fear of going off the road in a moments notice. It was 0 degrees outside this morning and even on damp patchy roads I could use wide open throttle in 2nd all the way to the red line with no issues, fantastic!

oddball1973 said: Got Pirelli Soto I's on the front (tyres are one year old and fitted them for the second year running) and had New Pirelli Soto III's fitted to the rear as the Original Soto 1 rears didn't fit (changed from 991S to 991 50th and the rear wheels are a different size) Handling has gone to s t (talking at 30mph plus) - car feels like its on wet mud, no feel, cambers in the road pulling it all over the place etc. Going back to the tyre fitters tomorrow but any ideas out there ?( Checked they've been fitted right in terms of rotation direction and they're all correct, Ican't believe there's a compatibility issue between I's and III's on paper but can't think what else it could be, the Soto I's front and rear on the previous car felt fine) I'm a Pirelli UK motorsport tyre dealer, and also have experience of a variety of different winter tyres on a variety of cars. Presuming you've checked pressures, and adjusted for ambient temperature..? For information, recommended pressures are stated at 20C, and pressure typically varies by 2psi per 10C. So if its 10C ambient, set the pressures at 2psi lower than the recommended pressure. As others have stated, the compound in these tyres is designed to operate at an ambient temperature of below 7C, above this, the blocks begin to move around more than designed, and this can lead to a 'numb' feeling when pushing on, and you can feel the blocks moving around under medium to hard barking and cornering. Having different tyre patterns front and rear isn't ideal, have you checked if you can get the SottoZero III fitted to the front too..? Different patterns front and rear, despite them both being Pirellis, can lead to a front/rear imbalance. I have driven various Porsches with matching front and rear Sotto Zeros, and at around 0C, they feel great. There is a bit more movement compared to a summer tyre, but thats to be expected. Sorry if I've just reiterated what you've already been told. Hope you sort it.

Hi we got it sorted, it was the mix of directional rears and asymmetric fronts that was causing the car to feel like it was driving on wet mud (the traction light was coming on over 40mph) Soon as asymetrics all round were fitted everything was fine. I think its worth bearing in mind SOTO I's and III's don't mix (I think the same would happen in any other cat not just a Porsche to be honest