Beware if using the R888R!
09-20-2017, 12:51 PM
#61
I just wanted to add some infos about some above mentioned tires in combination with our cars (996TT)in 18".
Toyo R888, Yokohama A052:
Can only be driven up to 300km/h with approval of the manufacture. So since our cars got a top speed of 305 km/h or more (S/WLS 307), its not allowed to use these tires at all.
Even the new Michelin Cup2 in stock turbo sizes got a no approval of the manufacture over 305km/h.
The only semi slick with an approval of the manufacture up to 315km/h is the new pirelli trofeo R.
So be very cautious when going really fast with these tires.
Toyo R888, Yokohama A052:
Can only be driven up to 300km/h with approval of the manufacture. So since our cars got a top speed of 305 km/h or more (S/WLS 307), its not allowed to use these tires at all.
Even the new Michelin Cup2 in stock turbo sizes got a no approval of the manufacture over 305km/h.
The only semi slick with an approval of the manufacture up to 315km/h is the new pirelli trofeo R.
So be very cautious when going really fast with these tires.
12-10-2017, 09:03 PM
#62
Burning Brakes
Just my 50 cents (a beginner about track days)
I started using Toyo R888r 2 years ago on my 993 carrera at first on 17” cup II: hot Tyre pressure was 2,0 bar front and 2,2 bar rear.
The grip was really good, but probably the tyre shoulder was too soft and they showed to be treaded on the side of the shoulder.I though an higher pressure would have been a better option, even if the handling and response was good.
this year I put 18” version ont OZ alleggerita and as long as I was using the tyres at 2,0/2,2 bars it was like driving on the soap both front and rear at breaking, cornering and accelerating, and this in any condition, both from start up and after couple of laps.
At lunch time, with legs under the table, a Porsche driver asked me what pressure I was using, and he told me I should use the same pressure as stated for street use.
So I tried 2,45 hot pressure front and 2,9 rear, and the tyres finally started to work as expected.
My car doesn’t have extreme camber, in the front almost nothing, what I can tell about the Toyo is that in both 17” and 18” size on the road they are simply amazing, probably the best choice on the market, because they are really good also on the wet (not heavy rain, only wet road), and I fact on the road the Tyre pressure was set as recommended by Porsche.
They fact is that they simply warm up quickly on the road and they never overcome their ideal working temperature.
But what represents a plus on the road, turns into a weakness on the track, because even with a spring air temperature of 25 degrees and clouds the window of available track laps is very short, if you don’t want to overcome the temperature and loose grip, 3 laps including the warm up lap and the game is over, if you want to make a better lap time.
So if on street use the GG compound is great, on track use could be good for time attack only or in very lower temperatures, like between 10 and 20 Celsius.
Then, I was surprised it was necessary to set the Tyre pressure so high, reasonably loosing the grip advantage related to a lower tyre pressure I cannot set, because with a lower pressure it was like driving a SUV: once I knew that, obviously I choose the precision and the response instead of a potential better grip.
The treadwear and grip are simply excellent, and for track days as well if you live in a region where also during warm season while driving towards the circuit there could be some wet: but then, once tracking, no endurance, but time attack only, unless temperatures aren’t like in Italy in late spring, summer and beginning of autumn.
this is a Tyre designed for a surgeon, I mean, someone who really knows the track he is lapping and how to drive, because there is just very few laps before exceeding their best working temperature: probably with lower air and ground temperatures one or two more laps would be available.
Related to this post, I think the failure was determined by multiple reasons: the camber, the low pressure (which makes the shoulders weaker), the compound which in my opinion is not for endurance.
Ignorance and not the tyres creates the problem: the most common way of setting the Tyre pressure when tracking a car is to reduce it, because you want more grip, but these Toyos need exactly the same pressure suggested by the car producer. Then if one drives them for several laps, out of their working temperature range and with high camber...maybe the probability of a failure becomes very high.
however, fortunately if used the right way, ie in the right conditions of air and ground temperature, inflation pressure and number of laps, the feeling of grip they offer and the feeling on the steering are really good, even when they have almost become slick, and also the lap time.
Next year I still don’t know which tyres to choose after having finished the 18” set of Toyo R888R: I was thinking Pirelli P zero trofeo R, but they have an softer compound, even if very probably their stiffer shoulder could allow to set a lower Tyre pressure.
Probably, in order to learn the circuit, one should first track the car with an harder and more stable compound, maybe Nankang, and only after having achieved a good confidence use the sticky tyres, trofeo R?
I started using Toyo R888r 2 years ago on my 993 carrera at first on 17” cup II: hot Tyre pressure was 2,0 bar front and 2,2 bar rear.
The grip was really good, but probably the tyre shoulder was too soft and they showed to be treaded on the side of the shoulder.I though an higher pressure would have been a better option, even if the handling and response was good.
this year I put 18” version ont OZ alleggerita and as long as I was using the tyres at 2,0/2,2 bars it was like driving on the soap both front and rear at breaking, cornering and accelerating, and this in any condition, both from start up and after couple of laps.
At lunch time, with legs under the table, a Porsche driver asked me what pressure I was using, and he told me I should use the same pressure as stated for street use.
So I tried 2,45 hot pressure front and 2,9 rear, and the tyres finally started to work as expected.
My car doesn’t have extreme camber, in the front almost nothing, what I can tell about the Toyo is that in both 17” and 18” size on the road they are simply amazing, probably the best choice on the market, because they are really good also on the wet (not heavy rain, only wet road), and I fact on the road the Tyre pressure was set as recommended by Porsche.
They fact is that they simply warm up quickly on the road and they never overcome their ideal working temperature.
But what represents a plus on the road, turns into a weakness on the track, because even with a spring air temperature of 25 degrees and clouds the window of available track laps is very short, if you don’t want to overcome the temperature and loose grip, 3 laps including the warm up lap and the game is over, if you want to make a better lap time.
So if on street use the GG compound is great, on track use could be good for time attack only or in very lower temperatures, like between 10 and 20 Celsius.
Then, I was surprised it was necessary to set the Tyre pressure so high, reasonably loosing the grip advantage related to a lower tyre pressure I cannot set, because with a lower pressure it was like driving a SUV: once I knew that, obviously I choose the precision and the response instead of a potential better grip.
The treadwear and grip are simply excellent, and for track days as well if you live in a region where also during warm season while driving towards the circuit there could be some wet: but then, once tracking, no endurance, but time attack only, unless temperatures aren’t like in Italy in late spring, summer and beginning of autumn.
this is a Tyre designed for a surgeon, I mean, someone who really knows the track he is lapping and how to drive, because there is just very few laps before exceeding their best working temperature: probably with lower air and ground temperatures one or two more laps would be available.
Related to this post, I think the failure was determined by multiple reasons: the camber, the low pressure (which makes the shoulders weaker), the compound which in my opinion is not for endurance.
Ignorance and not the tyres creates the problem: the most common way of setting the Tyre pressure when tracking a car is to reduce it, because you want more grip, but these Toyos need exactly the same pressure suggested by the car producer. Then if one drives them for several laps, out of their working temperature range and with high camber...maybe the probability of a failure becomes very high.
however, fortunately if used the right way, ie in the right conditions of air and ground temperature, inflation pressure and number of laps, the feeling of grip they offer and the feeling on the steering are really good, even when they have almost become slick, and also the lap time.
Next year I still don’t know which tyres to choose after having finished the 18” set of Toyo R888R: I was thinking Pirelli P zero trofeo R, but they have an softer compound, even if very probably their stiffer shoulder could allow to set a lower Tyre pressure.
Probably, in order to learn the circuit, one should first track the car with an harder and more stable compound, maybe Nankang, and only after having achieved a good confidence use the sticky tyres, trofeo R?
Anyway, this post made me think that maybe, the tyres producers, instead of thinking only to make a profit investing in advertisement, should provide detailed instructions how to set their tyres, both to optimize the performance and to reduce the failures, because many users are tracking their cars, and most of them aren’t informed at all...and they don’t have a circuit engineer as a supervisor/mentor...but the potential consequences and related responsibilities are very high.
12-10-2017, 09:25 PM
#63
Rennlist Member
You don't need an engineer, you just need a pyrometer. And running R-compound tires on a race track with a street alignment and street pressures will not provide you knowledge of their potential.
https://www.joesracing.com/rt-4219-t...mperature.html
https://www.joesracing.com/rt-4219-t...mperature.html
12-11-2017, 05:46 AM
#64
Burning Brakes
I read carefullly all the joesracing page you linked.
Unfortunately I don’t have a team when I go for a track day, but the technical advices could be useful to adjust the setting returning back home.
despite the almost street setting of the car, it was noticeable the change as I inflated then tyres with a higher air pressure, in terms of grip, handling, precision, accuracy of steering while hard breaking.
Plus with low tyre pressure at a certain corner the front tyres where evidently understeering and making a whistling noise,with higher tyre pressure no more understeer and no more whistling.
I don’t think the r888 r are going to work well with around 2.0 bars hot pressure Probably because of the balance and the weight of a 911, but this is just my personal thought.
Anyway, the first track days of 2018 will track the car with the used r888r and will verify tyre temperature close to the cord, to have a clearer idea first how to change cold tyre pressure and then how to adjust the front and rear settings when back home.
The joesracing page makes sense: spending money to have better hardware and then waste all the potential benefits because of a lack of accuracy avoiding to use the feedbacks that the tyres give for free isn’t really that smart.
In my case the car setting must be a compromise, because I cannot change it accordingly to each circuit.
What I noticed so far is also a very big handling and precision difference between pss10 system position 4 and position 9 while driving inside the track: the car changes compleately and also the way the tyres are worn out...it is evident that with a stiffer setting the tyres are worn out quicker, but the lap times drop considerably and the driving pleasure increases significantly.
I have no idea if the Pirelli Trofeo R could offer a better tyre performance, but they are available also in the size 235/40 for the front, so what could I expect in terms of driving balance ((cornering and breaking) installing a 10mm wider front tyre? Probably a bit less steering feeling and precision but a bit less understeer and better braking?
Unfortunately I don’t have a team when I go for a track day, but the technical advices could be useful to adjust the setting returning back home.
despite the almost street setting of the car, it was noticeable the change as I inflated then tyres with a higher air pressure, in terms of grip, handling, precision, accuracy of steering while hard breaking.
Plus with low tyre pressure at a certain corner the front tyres where evidently understeering and making a whistling noise,with higher tyre pressure no more understeer and no more whistling.
I don’t think the r888 r are going to work well with around 2.0 bars hot pressure Probably because of the balance and the weight of a 911, but this is just my personal thought.
Anyway, the first track days of 2018 will track the car with the used r888r and will verify tyre temperature close to the cord, to have a clearer idea first how to change cold tyre pressure and then how to adjust the front and rear settings when back home.
The joesracing page makes sense: spending money to have better hardware and then waste all the potential benefits because of a lack of accuracy avoiding to use the feedbacks that the tyres give for free isn’t really that smart.
In my case the car setting must be a compromise, because I cannot change it accordingly to each circuit.
What I noticed so far is also a very big handling and precision difference between pss10 system position 4 and position 9 while driving inside the track: the car changes compleately and also the way the tyres are worn out...it is evident that with a stiffer setting the tyres are worn out quicker, but the lap times drop considerably and the driving pleasure increases significantly.
I have no idea if the Pirelli Trofeo R could offer a better tyre performance, but they are available also in the size 235/40 for the front, so what could I expect in terms of driving balance ((cornering and breaking) installing a 10mm wider front tyre? Probably a bit less steering feeling and precision but a bit less understeer and better braking?
12-11-2017, 11:00 AM
#65
Rennlist Member
Pitting, having the pyrometer handy, and jumping out to check yourself really isn't that bad. Just have it in a door pocket or velcro'd down somewhere. I've also used an abandoned parking lot as a skidpad to try and get the pressures right.
You might look into the Bridgestone Re-71R tires. I've always heard good things about them and finally got to spend some time on them in an E36 M3. For a street tire, they were my absolute favorites. Much better feel than an NT01 (but about the same lap times.) I haven't checked sizing for an AWD TT yet though.
You might look into the Bridgestone Re-71R tires. I've always heard good things about them and finally got to spend some time on them in an E36 M3. For a street tire, they were my absolute favorites. Much better feel than an NT01 (but about the same lap times.) I haven't checked sizing for an AWD TT yet though.
12-14-2017, 07:30 AM
#66
Burning Brakes
Toyo r888 R is a great tyre, especially when the temperature of air and track aren't hot or warm, from 5 to maximum 20°C, which in my case represent a temperature from beginning of november until end of march/middle of april.
In this case these tyres have the ability to warm up really well and stay longer at the optimal operating temperature: I'd say they are great to be used at Nurburgring, where with the exception of a couple of months the temperatures are exactly in that range. Regarding the tyre failure, I think it depends also on the power of the car, the way it develops torque and its weight: I don't think a mezger turbo engine is as much gentle with the road as a gt3 mezger engine is.
Infact the tyres of turbo engined 911 go quicker out of temperature range than a GT3. The torsion stress onto the tire structure with an higher torque is obviously higher, even with the same power.
Talking about tyres, thank you slakker for your advices, it is evident the type of car, its specs, its set up, the track, the track conditions, the operating conditions, the way it is set, and the ispiration and hability of the driver count.
Too many variables to be able to say that a tire in general is dangerous or defective: it will certainly be, under certain conditions, on certain cars and used in a certain way. But each tyre could be that way under certain conditions.
But it should always be defective, regardless of any factor, then it should exhibit a number of faults that could lead the manufacturer to withdraw it from the market.
In my experience, it is 100% a really great tyre on the road, and for the track it is a perfect time attack tyre in the middle seasons, still good in the summer but with very small operating time window.
And this said, looking at the price, it costs almost half the price of Pirelli Trofeo R (which lasts optimisticallly talking 70% less track laps than the r888R) and of Dunlop DZ03G,which are considered the two best outperforming track days tyres.
The biggest limit of toyo, in my opinion, and on for my car type, is the not as stiff tyre shoulder as Pirelli Trofeo R has, which enables to reduce the operating tyre pressure to gain more grip.
Maybe on a lighter car, like catheram, super 7 and similar it works much better with such a shoulder.
For the next year I am considering the Nankang AR-1 option: they cost approximately the same as Toyo, but probably they go out of operating temperature after more laps than the toyo.
In this case these tyres have the ability to warm up really well and stay longer at the optimal operating temperature: I'd say they are great to be used at Nurburgring, where with the exception of a couple of months the temperatures are exactly in that range. Regarding the tyre failure, I think it depends also on the power of the car, the way it develops torque and its weight: I don't think a mezger turbo engine is as much gentle with the road as a gt3 mezger engine is.
Infact the tyres of turbo engined 911 go quicker out of temperature range than a GT3. The torsion stress onto the tire structure with an higher torque is obviously higher, even with the same power.
Talking about tyres, thank you slakker for your advices, it is evident the type of car, its specs, its set up, the track, the track conditions, the operating conditions, the way it is set, and the ispiration and hability of the driver count.
Too many variables to be able to say that a tire in general is dangerous or defective: it will certainly be, under certain conditions, on certain cars and used in a certain way. But each tyre could be that way under certain conditions.
But it should always be defective, regardless of any factor, then it should exhibit a number of faults that could lead the manufacturer to withdraw it from the market.
In my experience, it is 100% a really great tyre on the road, and for the track it is a perfect time attack tyre in the middle seasons, still good in the summer but with very small operating time window.
And this said, looking at the price, it costs almost half the price of Pirelli Trofeo R (which lasts optimisticallly talking 70% less track laps than the r888R) and of Dunlop DZ03G,which are considered the two best outperforming track days tyres.
The biggest limit of toyo, in my opinion, and on for my car type, is the not as stiff tyre shoulder as Pirelli Trofeo R has, which enables to reduce the operating tyre pressure to gain more grip.
Maybe on a lighter car, like catheram, super 7 and similar it works much better with such a shoulder.
For the next year I am considering the Nankang AR-1 option: they cost approximately the same as Toyo, but probably they go out of operating temperature after more laps than the toyo.