S02's on the rear...????
Discussion
Assuming you can get them in the correct size for the Griff the Vredestein Ultrac Sessantas have been getting very good reviews - I ordered a pair this morning from www.tyremen.co.uk for £115 each.
FWIW I’ve done a bit of research on whether the Bridgestone S02 N3 is a suitable replacement for the S-O2 Potenza Pole Position, mainly to reassure myself that the recent 245/45/ZR16s that I put on the rears of the Griffith are up to the job; here’s what I’ve found:
The Bridgestone S02 JZ N3 BSW is a Seat, Subaru (JZ) Original Equipment and Porsche approved tyre, where N3 indicates the level of enhancement from the original requirement specification (N0) for this tyre model.
What does N3 mean? "Porsche build high performance vehicles which require tyres suitable to meet expected performance levels. To this end, Porsche includes tyre selection in the development process of each vehicle. Tyres that have been selected, which have undergone the required tests and obtained validation by Porsche, are then accredited with an "N" specification." As far as I can tell N3 is not specifically restricted to the 911 and the tyre is also OE for Seat and Subaru.
The 245/45/ZR16 has the following specification:
Max load: 670 Kg at 51 psi max pressure
Treadwear: 140 Traction: A Temperature: A
Plies: Tread: 2 steel, 2 Rayon, 1 Nylon; Sidewall: 2 Rayon
For the Bridgestone Potenza S-02 Pole Position (which I have fitted on a spare set of 16/15 inch wheels), the id codes do not show any OE designation for or approval by TVR, but do for Ford/Mazda/Mercedes and VW approval (PZ). However, these tyres were sourced and fitted by a ‘high street’ tyre supplier and not through the then Approved TVR dealer that serviced the car, so that could explain the missing code. The tyre specification for the 205/55ZR15 is:
Max load: 545 Kg at 44 psi max pressure
Treadwear: 180 Traction: AA Temperature: A
Plies: Tread: 2 steel, 1 Rayon, 2 Nylon; Sidewall: 2 Rayon
So speed rating is OK but there are differences in the specification, where the Pole Position variant appears to be the better tyre in terms of wear and traction and with a different construction in the tread plies but similar construction in the sidewalls. Whether this gives a more compliant ride and progressiveness I don’t know yet.
Taking the above into consideration and the fact that the car is for ‘normal’ road use, I think I’ll ‘crack on’ and run this current set up until the tyres are ready for a four-tyre replacement and then appraise the alternatives, which at the moment is likely to be Toyo T1-R. Does anyone have the spec for these that they can post up just for comparison.
What also concerns me is the diminishing availability of tyres in sizes suitable for the original 16/15 inch wheels, which I want to keep.
Sorry for the long post.
The Bridgestone S02 JZ N3 BSW is a Seat, Subaru (JZ) Original Equipment and Porsche approved tyre, where N3 indicates the level of enhancement from the original requirement specification (N0) for this tyre model.
What does N3 mean? "Porsche build high performance vehicles which require tyres suitable to meet expected performance levels. To this end, Porsche includes tyre selection in the development process of each vehicle. Tyres that have been selected, which have undergone the required tests and obtained validation by Porsche, are then accredited with an "N" specification." As far as I can tell N3 is not specifically restricted to the 911 and the tyre is also OE for Seat and Subaru.
The 245/45/ZR16 has the following specification:
Max load: 670 Kg at 51 psi max pressure
Treadwear: 140 Traction: A Temperature: A
Plies: Tread: 2 steel, 2 Rayon, 1 Nylon; Sidewall: 2 Rayon
For the Bridgestone Potenza S-02 Pole Position (which I have fitted on a spare set of 16/15 inch wheels), the id codes do not show any OE designation for or approval by TVR, but do for Ford/Mazda/Mercedes and VW approval (PZ). However, these tyres were sourced and fitted by a ‘high street’ tyre supplier and not through the then Approved TVR dealer that serviced the car, so that could explain the missing code. The tyre specification for the 205/55ZR15 is:
Max load: 545 Kg at 44 psi max pressure
Treadwear: 180 Traction: AA Temperature: A
Plies: Tread: 2 steel, 1 Rayon, 2 Nylon; Sidewall: 2 Rayon
So speed rating is OK but there are differences in the specification, where the Pole Position variant appears to be the better tyre in terms of wear and traction and with a different construction in the tread plies but similar construction in the sidewalls. Whether this gives a more compliant ride and progressiveness I don’t know yet.
Taking the above into consideration and the fact that the car is for ‘normal’ road use, I think I’ll ‘crack on’ and run this current set up until the tyres are ready for a four-tyre replacement and then appraise the alternatives, which at the moment is likely to be Toyo T1-R. Does anyone have the spec for these that they can post up just for comparison.
What also concerns me is the diminishing availability of tyres in sizes suitable for the original 16/15 inch wheels, which I want to keep.
Sorry for the long post.
Edited by davep on Thursday 19th August 18:07
As an aside the Toyo T1R is being replaced with the T1 Sport - of which I have the 225/55/16 version on the rear axle right now. Fronts are S03PPs which came with a spare pair of OZ split rims that I bought. The idea was to have a stiffer sidewall on the front for better turn-in response versus the SP9000s I also have, and the softer Toyos (that are pretty similar to the Bridgestones in other aspects to keep the rear end smooth, progrssive and feelsome - everything based on a gut feeling about what the car needs, but it seems to have worked out well so far.
26 here too.Well I've been running the "new" So2's on the back of mine for around 3 years. I've always managed to keep it on the black stuff saying that I need some new fronts so will be going for the SP2000's only purely because they are the correct speed rating. In all honestly how hard can you drive the car these days in the UK to tell a difference in tyres?
Contacted Bridgestone yesterday and they said due to their construction N spec tyres are not suitable for fitment to any other car but Porsche. I pointed out that some tyre suppliers are not making this fact absolutely clear in their online ordering process, and was told that's the tyre supplier's responsibility and Bridgestone have no control over how tyres are advertised. So buyer beware!
However, I found these threads interesting:
http://www.pistonheads.com/gassing/topic.asp?h=28&...
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Some think N approval is de rigueur, others are sceptical, as am I. Similar 'restrictive' approval schemes are run by Ferrari and Audi.
Also mixing brands front and rear is now considered a big no-no.
FWIW the 245/45/16 size was mostly used on the front engine- rear wheel drive 944 and 968 models.
However, I found these threads interesting:
http://www.pistonheads.com/gassing/topic.asp?h=28&...
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Some think N approval is de rigueur, others are sceptical, as am I. Similar 'restrictive' approval schemes are run by Ferrari and Audi.
Also mixing brands front and rear is now considered a big no-no.
FWIW the 245/45/16 size was mostly used on the front engine- rear wheel drive 944 and 968 models.
Edited by davep on Sunday 22 August 13:03
penno said:
Well I've been running the "new" So2's on the back of mine for around 3 years. I've always managed to keep it on the black stuff saying that I need some new fronts so will be going for the SP2000's only purely because they are the correct speed rating. In all honestly how hard can you drive the car these days in the UK to tell a difference in tyres?
Looks like they do a reasonable job then, that's good to know.JR said:
davep said:
Where's that parrot picture?
Do you really think that Porsche engineers have come to the conclusion that a rear mid/engined 911 needs exactly the same spec tyre as a lightweight rwd car?http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Maybe this Chimaera owner had his engine mounted in the boot!
You don’t work for Toyo now do you?
BTW please don't misqoute, nor use the 3rd person with
, it's not polite.
davep said:
JR said:
davep said:
Where's that parrot picture?
Do you really think that Porsche engineers have come to the conclusion that a rear mid/engined 911 needs exactly the same spec tyre as a lightweight rwd car?http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Maybe this Chimaera owner had his engine mounted in the boot!
No, I did not recommend Porsche tyres to a Chim owner. In the thread that you quote the TVR owner did not want one of the few normally recommended alternatives so I suggested the Pirelli, we never did get into the reasons why. I mentioned the Ferrari/Porsche OE fitment because I think that Pirelli get too rough a deal on the site. There are two things about that range of tyres (PZeroA) - firstly the sidewalls are known to be soft, too soft really for there nominal cars (hence the typical comments) which ironically makes them more suitable for TVRs and secondly there are quite a few types (just like the SO2) some of which are suitable for TVRs and some of which are suitable for Porsches (just like the SO2.)
I'm not sure where you're trying to head with this thread. SO1s were great albeit wearing out quickly, SO2PPs were ideally suited to TVRs, more by fluke than anything else IMHO, but you can't buy them now. If you want the best performing tyres for your TVR then Bridgestone are not likely to be the top of your list and even then not the SO range (do they make their UHP tyres in suitable sizes?) Your SO2 tyres are not a death trap, just depends how you drive the car.
No, I don't work or have an interest in Toyo: eg the groove at the edge of the T1-R means that the tread does not perform well or last well as the T1-S when pushed hard, esp. on the track.
JR said:
davep said:
JR said:
davep said:
Where's that parrot picture?
Do you really think that Porsche engineers have come to the conclusion that a rear mid/engined 911 needs exactly the same spec tyre as a lightweight rwd car?http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Maybe this Chimaera owner had his engine mounted in the boot!
No, I did not recommend Porsche tyres to a Chim owner. In the thread that you quote the TVR owner did not want one of the few normally recommended alternatives so I suggested the Pirelli, we never did get into the reasons why. I mentioned the Ferrari/Porsche OE fitment because I think that Pirelli get too rough a deal on the site. There are two things about that range of tyres (PZeroA) - firstly the sidewalls are known to be soft, too soft really for there nominal cars (hence the typical comments) which ironically makes them more suitable for TVRs and secondly there are quite a few types (just like the SO2) some of which are suitable for TVRs and some of which are suitable for Porsches (just like the SO2.)
I'm not sure where you're trying to head with this thread. SO1s were great albeit wearing out quickly, SO2PPs were ideally suited to TVRs, more by fluke than anything else IMHO, but you can't buy them now. If you want the best performing tyres for your TVR then Bridgestone are not likely to be the top of your list and even then not the SO range (do they make their UHP tyres in suitable sizes?) Your SO2 tyres are not a death trap, just depends how you drive the car.
No, I don't work or have an interest in Toyo: eg the groove at the edge of the T1-R means that the tread does not perform well or last well as the T1-S when pushed hard, esp. on the track.
I was following the thread on the advantages and disadvantages of larger wheel sizes and stumbled across the old Chimaera topic after a Google search. As much as I'd like to read through all your TVR related posts I just don't have the time. Interesting to read Mark Hales and PRW weren't too keen on the move towards big wheels.
To the point: What would you recommend size and brand wise for an early pre-cat Griffith, no rear ARB, 15/16 inch AMILs, Bilstein shocks, with spirited road miles and the odd track day?
Thanks.
Edited by davep on Monday 23 August 09:40
Sorry to bang on but this post maybe of interest to other TVR pre-cat Griffith owners where their car has no rear ARB and is fitted with the standard 16 inch rear and 15 inch front wheels. The post is IMO.
After extensive road testing over several months, I’ve concluded that high profile Toyos are too soft for my car, this is possibly down to the lack of rear ARB and my driving style. I found that once tyre pressures were high enough to compensate for their tendency to replicate a bouncy castle, the ride was overly hard sending the car into hedge-seeking mode. I couldn’t find a tyre pressure compromise that I was happy with.
I’ve scoured the tyre supplier web sites only to be ‘limited’ to a correctly sized and speed rated tyre, which, although approved by Porsche, does allow lower tyre pressures (24psi/22psi) which give me a more controllable ride. This tyre being the Bridgestone SO2 N3.
With regard to the N designation, I’ve contacted a selection of UHP tyre manufacturers and the consensus is as follows:
The N designation is a specific tyre composition for use on Porsche vehicles due to their usually high power outputs. As such, the tyres are slightly softer compared to the standard tyres in order to aid overall grip characteristics.
After extensive road testing over several months, I’ve concluded that high profile Toyos are too soft for my car, this is possibly down to the lack of rear ARB and my driving style. I found that once tyre pressures were high enough to compensate for their tendency to replicate a bouncy castle, the ride was overly hard sending the car into hedge-seeking mode. I couldn’t find a tyre pressure compromise that I was happy with.
I’ve scoured the tyre supplier web sites only to be ‘limited’ to a correctly sized and speed rated tyre, which, although approved by Porsche, does allow lower tyre pressures (24psi/22psi) which give me a more controllable ride. This tyre being the Bridgestone SO2 N3.
With regard to the N designation, I’ve contacted a selection of UHP tyre manufacturers and the consensus is as follows:
The N designation is a specific tyre composition for use on Porsche vehicles due to their usually high power outputs. As such, the tyres are slightly softer compared to the standard tyres in order to aid overall grip characteristics.
davep said:
Sorry to bang on but this post maybe of interest to other TVR pre-cat Griffith owners where their car has no rear ARB and is fitted with the standard 16 inch rear and 15 inch front wheels. The post is IMO.
After extensive road testing over several months, I’ve concluded that high profile Toyos are too soft for my car, this is possibly down to the lack of rear ARB and my driving style. I found that once tyre pressures were high enough to compensate for their tendency to replicate a bouncy castle, the ride was overly hard sending the car into hedge-seeking mode. I couldn’t find a tyre pressure compromise that I was happy with.
I’ve scoured the tyre supplier web sites only to be ‘limited’ to a correctly sized and speed rated tyre, which, although approved by Porsche, does allow lower tyre pressures (24psi/22psi) which give me a more controllable ride. This tyre being the Bridgestone SO2 N3.
With regard to the N designation, I’ve contacted a selection of UHP tyre manufacturers and the consensus is as follows:
The N designation is a specific tyre composition for use on Porsche vehicles due to their usually high power outputs. As such, the tyres are slightly softer compared to the standard tyres in order to aid overall grip characteristics.
Are your insurers happy with these?After extensive road testing over several months, I’ve concluded that high profile Toyos are too soft for my car, this is possibly down to the lack of rear ARB and my driving style. I found that once tyre pressures were high enough to compensate for their tendency to replicate a bouncy castle, the ride was overly hard sending the car into hedge-seeking mode. I couldn’t find a tyre pressure compromise that I was happy with.
I’ve scoured the tyre supplier web sites only to be ‘limited’ to a correctly sized and speed rated tyre, which, although approved by Porsche, does allow lower tyre pressures (24psi/22psi) which give me a more controllable ride. This tyre being the Bridgestone SO2 N3.
With regard to the N designation, I’ve contacted a selection of UHP tyre manufacturers and the consensus is as follows:
The N designation is a specific tyre composition for use on Porsche vehicles due to their usually high power outputs. As such, the tyres are slightly softer compared to the standard tyres in order to aid overall grip characteristics.
FFG
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