Tyres again, but a bit different

[Guest]

My C2 is currently shod with Pirelli P Zero N2s - Direzionales at the front and Asimetricos at the rear. The rears are getting a bit thin and I'm looking to change, but P Zeros are no longer available.

The nice people at Michedever Tyres say that P Zero Rosso N3s on the rear can be combined with PZ N2 Direzionales at the front, but suggest that I check with Porsche GB to be sure.

Anyone here got a view?

 

[John Maddox]

Pretty sure an OPC will say all N numbers must be the same.

 

[Sundeep]

this highlights the tyre combo problems from Pirelli, due to their range....

but having the same set from the same manufacturer per axle should be fine for the real world but you will need to see how it feels, no reason why it shouldn't as long as they are all n rated.... obviously it is better to have all 4 corners of the exact same spec as this is the recommended position from Porsche...

ORIGINAL: MoC2S

Peter, it's not an approved combination. Doesn't mean it would not be OK, but I suspect the Rossos are designed to last a bit longer than the vanilla Asimmetricos, so oversteer might be the order of the day ...

oversteer! [] you make it sound like pete is going to be skating all over the road !

 

[willstatt]

I recently needed two new rears on my 993 C4. It had Pzero N3's all round. The front tyres have loads of life left in them. I had two new Pzero N4's because that was all that was available, and my fitter says that is perfectly acceptable. The car handles just as well as it did before. (£250 each plus vat by very good small supplier in Shepshed Leicestershire)

 

[Sundeep]

now now old chap...

I did say that a matched pair from the same manufacturer per axle is a min' requirement..

certainly would never say have 4 different tyres... as that would be every wrong [&o]

 

[Sundeep]

of course not, I always read and review everything that is said....

 

[willstatt]

Hi Maurice,

No, the ones on the front are PZ Asimmetrico N3 ZR's and the new ones on the rear are PZ Rosso N4 ZR's

My chap fits lots of tyres to performance cars and knows his stuff he assures me that the combination is fine. They handle perfectly.

I don't doubt Pirelli don't recommend it... after all they would rather I bought a set of FOUR new tyres wouldn't they. I think it's a bit like the question of repairable tyres... so many are condemned when in fact they are repairable, because the manufacturers A. want you to buy new, and B. want to avoid the tiniest chance of litigation, in the event of someone saying the supposed mismatch or repair,caused them to have an accident.

I wouldn't mix makes, and I wouldn't mix specs on one axle, but as far as I'm concerned the mix that I have is perfectly safe. and perfectly compatible.

By the way, the price in my earlier post should have read £150 each plus vat!

Will

 

[Guest]

ORIGINAL: MoC2S

<snip>

There is a blanket ruling on ZR rated tyres .... no repairs, period.

<snip>

cheers, Maurice []

Maurice, this is news to me. Could you point me to the relevant rules.

Thanks

Bob

 

[willstatt]

Hi Maurice,

When you say my tyre combination is "un-approved" what exactly do you mean? Do you mean that it is expressly advised against (for a particular reason?) or that it is simply not one of Pirelli's/Porsche's approved optimum setups, but that there is no reason why it can't be used.... if you get my drift?

As for handling... I've now used the car in all conditions over the last 6 weeks: Ice; gritty roads; heavy rain; and nice and dry (like today in Leicestershire) In all cases there is no discernable problem or variation in grip and the car feels perfectly stable.

I do think there is a lot of twaddle with this tyre subject, and a lot of it is 'engineered' to produce more tyre sales.

Will

 

[Sundeep]

ORIGINAL: willstatt
When you say my tyre combination is "un-approved" what exactly do you mean? Do you mean that it is expressly advised against (for a particular reason?) or that it is simply not one of Pirelli's/Porsche's approved optimum setups, but that there is no reason why it can't be used.... if you get my drift?

what Porsche actually say is some what open some intrepretation in the real world if you consider the complexities of N rated tyres... as one of the key terms used is that Porsche recommend that matching N rated tyres are used all the way around, but in the same way Porsche owners fit Pagid Brake Pads, whereas Porsche recommend fitting their OEM Pads....... I can understand and agree why 4 mixed tyres of any combo is wrong,

but the only exception to 4 matching n rated tyres that I see as permissable is if that all the tyres are at least of the same manufacturer and (obvious all n rated) by each axle has a different N rated spec e.g. you may have N4 Pirelli's on the rears and N3's Pirelli's on the front, etc etc and that is the only different front to rear, not side to side !

as when I bought my car, I had Contiential Sport N1's on the Front and Contiential Sport N2's on the back, and they were fine for the 10k miles thst they lasted, whch included a few track days as well... and I did not see the value in spend £400 to get fully matching tyres and if I had to change a tyre I would have kept to Conti's to ensure the right balance..

obvious if you can fit the same 4 N rated tyres all the way around this is the correct option, (which is what I have right now, Michelin Pilot Sport N2's so avoiding the multi-combo Pirelli options!) but I can understand if one tyre suffers a failure and you are faced with having to replace all 4 tyres as your current N spec is no longer available, afterall we are not all millionaires who drive their cars at the performance limit all the time !

I don't know it they have actually said the unword unapproved unless Maurice would care to enlighten us ?

to aid in this debate.... here is an exact from an artcile from a US Tyre (they spell it Tire!) site

It is recommended that only matching tires be used on Porsche vehicles. Since many Porsche vehicles are fitted with differently sized tires on their front and rear axles, this means matching the tire make, tire type and N-specification. If a vehicle was originally delivered with N-specification tires that have been discontinued and are no longer available, it is recommended to change all four tires to a higher numeric N-specification design appropriate for that vehicle. Mixed tire types are not permissible.

It is also important to know that while Porsche N-specification tires have been fine tuned to meet the specific performance needs of Porsche vehicles, the tire manufacturers may also build other tires featuring the same name, size and speed rating as the N-specification tires for non-Porsche applications. These tires may not be branded with the Porsche N-specification because they do not share the same internal construction and/or tread compound ingredients as the N-specification tires. Using tires that are not N-specific is not recommended and mixing them with other N-specification tires is not permissable.

Tires should be replaced no less than in pairs on one axle at a time. Only tires of the same tire make and type must be used. However, in case of tire damage such as cuts, punctures, cracks or sidewall bulges that cause a single tire to be replaced for safety reasons, the remaining matching tire on that axle must not exceed 30 percent wear. If the remaining tire has more than 30 percent wear from new, it should also be replaced. Handling inconsistencies may result if this is not done.

Initially, new tires do not offer their full traction. Drivers should therefore drive at moderate speeds during the first 60-100 miles (100-200 km). If new tires are installed on only one axle, a noticeable change in handling occurs due to the different tread depth of the other tires. This happens especially if only rear tires are replaced. However, this condition disappears as new tires are broken in. Drivers should adjust their driving style accordingly.

NOTE: The last two paragraphs are excerpts from recent Porsche vehicle owner's manuals.

 

[willstatt]

Maurice, I wouldn't for one moment denigrate Porsche's testing process, and I'm sure my tyre man wouldn't give a guarantee of the suitability of my combination.

However, as you say:

"Porsche have not tested / approved Asimmetricos in combination with anything except Direzionales as designed for the PZero System."

So they too don't know how that combination performs? That is surely why they don't recommend it... because they haven't tested it rather than because they have, and found it lacking.

I agree that the Porsche approval system is intended to guide people, and point them towards known, safe, setups. But that doesn't mean that another setup is not safe.

My own intention was to buy and fit PZero N3 tyres, but they were not available. My man said that the N4 Rosso's were fine. Logic led me to agree. The alternative would be to believe that Pirelli would produce one Porsche approved tyre (my front N3's for example) and then produce another Porsche approved tyre, (my new N4's) but the characteristics of the latter tyre were so different to the preceding model, that it made it unsafe for use in combination with the former.

I accept the Porsche testing system but am sure that if they tested 'my' combination, that they would surely find no problem with it.

If that is not the case, then it is very dodgy practice of Pirelli to keep changing the spec of their tyres so that one always effectively had to buy a new full set of the latest spec, because the older were unavailable?

This is all from my little brain and has no scientific basis.

Will

 

[Guest]

Fellas, thanks for the thoughts/input and the discussion generally. I think I'll be going for the PZ Rossos...

Maurice, am I right in thinking - from one of your posts - that the chat you had with Porsche GB was about PZ Direzionale N2 front and PZ Rosso N3 rear? Or was it more general???

 

[Sundeep]

ORIGINAL: MoC2S

ORIGINAL: Sundeep993

what Porsche actually say is some what open some intrepretation in the real world if you consider the complexities of N rated tyres... as one of the key terms used is that Porsche recommend that matching N rated tyres are used all the way around, but in the same way Porsche owners fit Pagid Brake Pads, whereas Porsche recommend fitting their OEM Pads....... I can understand and agree why 4 mixed tyres of any combo is wrong,

but the only exception to 4 matching n rated tyres that I see as permissable is if that all the tyres are at least of the same manufacturer and (obvious all n rated) by each axle has a different N rated spec e.g. you may have N4 Pirelli's on the rears and N3's Pirelli's on the front, etc etc and that is the only different front to rear, not side to side !

Strictly speaking that is not a Porsche Approved fitting. The actual wording used in official Porsche notices is reproduced elsewhere, but ....

>>> If new tires are to be mounted or the tires of one axle are to be replaced, tires of the same make, the same type and with the same specification code must always be used on each of the two axles. >>> Absolutely unequivocal, no wriggle room, no 'recommend'. Approval is quite black and white ... [8|]

more reasons to stay away from the not so simple Pirelli tyre catalogue and rather stick to the Pirelli Calendar, which is less confusing....

[]