Boxster Front Tyres.
Discussion
..The front Michelin Pilot SP2's need replacing on my Boxster. The standard size is 225/40x18. My
local tyre specialist has 235/40x18 that he has on the shelf and will do a 'deal' for me. Can anyone
confirm this tyre size will fit ok and will it cause any other issues?
Thanks for your input.
local tyre specialist has 235/40x18 that he has on the shelf and will do a 'deal' for me. Can anyone
confirm this tyre size will fit ok and will it cause any other issues?
Thanks for your input.
Matching collars and cuffs are have a certain appeal in my book, but you can deviate brands / N or non-N front to back, if you wish.
On the other side of the pond, the track day crowd sometimes put 235s on the front to reduce understeer but I believe that they drop the aspect ratio to keep the rolling circumference / or wheel arch clearance (not sure which) the same.
Not sure but it is also possible that you might end up confusing the PSM system...
In summary, if the sole reason for considering these 235s is to save some cash, I would be tempted to choose another brand but stick with the correct size.
However, fronts last so long on the Boxster I would be inclined to pay the going rate for N spec PS2 and be done with it.
(I ran Dunlops [S-02] for the past couple of years to save cash but they were so noisy, I regretted it).
On the other side of the pond, the track day crowd sometimes put 235s on the front to reduce understeer but I believe that they drop the aspect ratio to keep the rolling circumference / or wheel arch clearance (not sure which) the same.
Not sure but it is also possible that you might end up confusing the PSM system...
In summary, if the sole reason for considering these 235s is to save some cash, I would be tempted to choose another brand but stick with the correct size.
However, fronts last so long on the Boxster I would be inclined to pay the going rate for N spec PS2 and be done with it.
(I ran Dunlops [S-02] for the past couple of years to save cash but they were so noisy, I regretted it).
Edited by MogulBoy on Thursday 13th June 13:49
MogulBoy said:
Matching collars and cuffs are have a certain appeal in my book, but you can deviate brands / N or non-N front to back, if you wish.
???? There would be much less difference between N and non N of the same tyre than between brands. Edited by anonymous-user on Thursday 13th June 13:49
I dread to think how a car with eg. PS2s on the rear and P Zeros on the front would handle, whilst I doubt anyone could tell the difference beween N and non N of the same tyre.
REALIST123 said:
???? There would be much less difference between N and non N of the same tyre than between brands.
I dread to think how a car with eg. PS2s on the rear and P Zeros on the front would handle, whilst I doubt anyone could tell the difference beween N and non N of the same tyre.
There's a lot of opinions out there and many previous threads on this subject but fundamentally, what you need to keep in mind is the balance of available grip front to back and how that changes over time as tyres wear...I dread to think how a car with eg. PS2s on the rear and P Zeros on the front would handle, whilst I doubt anyone could tell the difference beween N and non N of the same tyre.
When you start of with a set of 4 matching tyres, you have a 'base line' level of grip and should have predictible handling.
When you get to the point that the rears are approaching 'fully worn', the grip from the rear will be considerably less than when the tyres were new. However, you will find that the fronts should still have plenty of life left in them. The result is that there will be more potential for oversteer while this imbalance persists. Great when you want to pretend that you have more power, not so good if you end up spinning on a greasy roundabout...
What happens next is that assuming that you have fitted new rears, the balance of grip is temporarily restored to within a 'normal' window but as the miles pile on, the fronts will approach the end of their lives and you may begin to experience some/more understeer (due to the excess of rear grip over front grip).
If you follow the above logic, you will appreciate that it does not matter if you don't have matching tyres front to back (side to side is a different kettle of fish) as long as you are always conscious of the relative grip front to back and how this changes over time as the tyres wear and drive around it.
i.e. So there's no reason why PS2 N on the back and PZero on the front wouldn't be a perfectly acceptable solution.
Regarding the N non-N debate... I don't beleive that the tyre companies, or Porsche, ever come clean about the exact differences. Some of these could be 'invisible' such as the use of different compounds (doubtful, but possible) and different sidewall constructions. It's possible that it's just a cosy marketing arrangement and there are no practical differences. However, at one point in time the non-N spec PS tyres had a totally different tread pattern on them (V shape verus the Ribbed pattern found on the N-spec tyres). Not sure if you can still buy the non-N spec PS tyres but you get my drift?
My preference is to match front to back but to be honest, that's largely for aesthetic reasons. Safety and performance is well covered simply by choosing 'good' tyres and remembering to change them way before the legal limit.
P.S. I had some N-spec Dunlop S-02 tyres on my 986 and to be honest they were so noisy they were unpleasant and it took an Porsche tech. to confirm to that it was the brand new tyres and not dodgy wheelbearings that I was hearing. The OPC in question offered to change them for free if I had bought them there (but I hadn't). Although N-spec, the tyres in question were 'certified' for the 993 and therefore, not automatically the best choice for the 986 (different suspension, weight distribution etc) albeit available in the correct sizes, they appear to be a bad choice for the 986 in 17".
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