Pics & Review of My Bilstein PSS10 Lowered Red Turbo
#496
09-02-2013, 10:59 AM
Join Date: Dec 2006
Location: Palos Verdes
Posts: 3,116
Rep Power: 254 
Very interesting quote from famous driver (like to guess who it is?), when approached about the idea of using racing tire on a standard 997.2 Turbo:
"Ok, that will be faster but my experience is that if you put a slick tire (note: meaning tire with great sticky rubber, but very stiff wall) on a standard car, then the suspension is too soft is too soft. You get too much rolling, because you have too much side force. Then you have to also change the suspension. That's our experience even on the GT3. As soon as you put slick tires on, you must also increase the spring rate."
My main take from this (anyone feels free to chime in) is tire is a crucial part of the suspension system, and the components of the "system" should be "appropriate" for each other. A sticky, stiff-walled tire is best matched with a stiffened suspension.
Mix matching is of course ok, since we are all amateurs here, not professionals trying to squeeze out another millisecond, but theoretically it's not ideal. In other words, if you are going to use R comp on your Turbo, best to stiffen up the spring with a stiffer coilover, or stiffer lowering springs, etc.
"Ok, that will be faster but my experience is that if you put a slick tire (note: meaning tire with great sticky rubber, but very stiff wall) on a standard car, then the suspension is too soft is too soft. You get too much rolling, because you have too much side force. Then you have to also change the suspension. That's our experience even on the GT3. As soon as you put slick tires on, you must also increase the spring rate."
My main take from this (anyone feels free to chime in) is tire is a crucial part of the suspension system, and the components of the "system" should be "appropriate" for each other. A sticky, stiff-walled tire is best matched with a stiffened suspension.
Mix matching is of course ok, since we are all amateurs here, not professionals trying to squeeze out another millisecond, but theoretically it's not ideal. In other words, if you are going to use R comp on your Turbo, best to stiffen up the spring with a stiffer coilover, or stiffer lowering springs, etc.
#497
09-02-2013, 12:09 PM
Very interesting quote from famous driver (like to guess who it is?), when approached about the idea of using racing tire on a standard 997.2 Turbo:
"Ok, that will be faster but my experience is that if you put a slick tire (note: meaning tire with great sticky rubber, but very stiff wall) on a standard car, then the suspension is too soft is too soft. You get too much rolling, because you have too much side force. Then you have to also change the suspension. That's our experience even on the GT3. As soon as you put slick tires on, you must also increase the spring rate."
My main take from this (anyone feels free to chime in) is tire is a crucial part of the suspension system, and the components of the "system" should be "appropriate" for each other. A sticky, stiff-walled tire is best matched with a stiffened suspension.
Mix matching is of course ok, since we are all amateurs here, not professionals trying to squeeze out another millisecond, but theoretically it's not ideal. In other words, if you are going to use R comp on your Turbo, best to stiffen up the spring with a stiffer coilover, or stiffer lowering springs, etc.
"Ok, that will be faster but my experience is that if you put a slick tire (note: meaning tire with great sticky rubber, but very stiff wall) on a standard car, then the suspension is too soft is too soft. You get too much rolling, because you have too much side force. Then you have to also change the suspension. That's our experience even on the GT3. As soon as you put slick tires on, you must also increase the spring rate."
My main take from this (anyone feels free to chime in) is tire is a crucial part of the suspension system, and the components of the "system" should be "appropriate" for each other. A sticky, stiff-walled tire is best matched with a stiffened suspension.
Mix matching is of course ok, since we are all amateurs here, not professionals trying to squeeze out another millisecond, but theoretically it's not ideal. In other words, if you are going to use R comp on your Turbo, best to stiffen up the spring with a stiffer coilover, or stiffer lowering springs, etc.
#498
09-04-2013, 02:49 PM
Join Date: Dec 2006
Location: Palos Verdes
Posts: 3,116
Rep Power: 254
>>>>>>>
Originally posted by pwdrhound
....Every input is very sharp and the car became much more stable under hard braking since the rear was no longer toeing out as a result of the rubber compressing under hard braking....
>>>>>>>
Thnx for the interesting comment.
1. By rear, you meant rear tire I assume? Rear tire toeing out under braking: is this normal expected behavior of our 911?
2. How could you tell that toe-out was lessened? Less oversteer? Less tire wear?
Originally posted by pwdrhound
....Every input is very sharp and the car became much more stable under hard braking since the rear was no longer toeing out as a result of the rubber compressing under hard braking....
>>>>>>>
Thnx for the interesting comment.
1. By rear, you meant rear tire I assume? Rear tire toeing out under braking: is this normal expected behavior of our 911?
2. How could you tell that toe-out was lessened? Less oversteer? Less tire wear?
#499
09-04-2013, 03:32 PM
>>>>>>>
Originally posted by pwdrhound
....Every input is very sharp and the car became much more stable under hard braking since the rear was no longer toeing out as a result of the rubber compressing under hard braking....
>>>>>>>
Thnx for the interesting comment.
1. By rear, you meant rear tire I assume? Rear tire toeing out under braking: is this normal expected behavior of our 911?
2. How could you tell that toe-out was lessened? Less oversteer? Less tire wear?
Originally posted by pwdrhound
....Every input is very sharp and the car became much more stable under hard braking since the rear was no longer toeing out as a result of the rubber compressing under hard braking....
>>>>>>>
Thnx for the interesting comment.
1. By rear, you meant rear tire I assume? Rear tire toeing out under braking: is this normal expected behavior of our 911?
2. How could you tell that toe-out was lessened? Less oversteer? Less tire wear?
2. I could tell toe out was lessened because the rear end of the car became much more solid under hard braking, it was much more stable and tracking straight if you will. Since all 911s are tail heavy, there is a natural pendulum effect for the rear end to come around especially if unsettled mid turn. If you have your rear tires toeing out under hard braking its a double whammy as the back end becomes light at the same time making it that more easier for the back of the car to step out. Add toe out to the mix and you can see how the back of the car will become unstable and is prone to oversteer as weight is transferred from one rear wheel to another. You will actually feel the back of the car dancing around a bit. Locking down the rear by eliminating the compressible rubber in the lower control arms via solid thrust arm bushing and monoball ends allows you to maintain the correct geometry in the rear. A good LSD with a moderate preload also helps in stabilizing the car under braking because it effectively ties the two rear wheel together which also adds straight line stability under hard braking. All of this really comes into play once you start driving the car at the limit on the track with some sticky tires. Hope that helps...
Last edited by pwdrhound; 09-04-2013 at 03:37 PM.
#501
09-08-2013, 12:24 PM
Join Date: Dec 2006
Location: Palos Verdes
Posts: 3,116
Rep Power: 254
Good news for folks in California; particularly Southern Cal. If you drive the 405 past Carson/South Bay area, I am sure you've noticed for the last few months work has begun on what promises to be a **HUGE** Porsche Experience Center and Track, built with all of western US in mind.
I believe the land deal went through during the 2006-2012 real estate bubble burst, when anyone with $$$ should have/could have/would have
scooped up properties for cheap. Rich Porsche did get richer with perfect timing here.
I believe the land deal went through during the 2006-2012 real estate bubble burst, when anyone with $$$ should have/could have/would have
scooped up properties for cheap. Rich Porsche did get richer with perfect timing here.
#503
09-11-2013, 01:02 PM
Join Date: Dec 2006
Location: Palos Verdes
Posts: 3,116
Rep Power: 254
Tire update:
Finally after 2 years and 20,000 miles (!!), my Michelin PSS are all worn out and will need to be changed. This is, by far, the longest life I have EVER had for tires on my 2 Porsches, and by a wide margin.
Even though I should/could just replace with PSS, I will try the fabled Bridgestone RE 11 next, just for fun. Bridgestone RE 11 costs the same as PSS but is expected to last maybe 12000 miles per my tire store's opinion, or half as much as the PSS, in effect costing nearly twice as much, I think.
PSS is truly a game changer, so sticky and yet such incredible tread wear life. The only thing I didn't like about it (personal preference) is that sidewall is relative soft so car is comfortable but body rolls more.
Finally after 2 years and 20,000 miles (!!), my Michelin PSS are all worn out and will need to be changed. This is, by far, the longest life I have EVER had for tires on my 2 Porsches, and by a wide margin.
Even though I should/could just replace with PSS, I will try the fabled Bridgestone RE 11 next, just for fun. Bridgestone RE 11 costs the same as PSS but is expected to last maybe 12000 miles per my tire store's opinion, or half as much as the PSS, in effect costing nearly twice as much, I think.
PSS is truly a game changer, so sticky and yet such incredible tread wear life. The only thing I didn't like about it (personal preference) is that sidewall is relative soft so car is comfortable but body rolls more.
Tire Update
I now have had Michelin PSS for 18 months or so and following is an updated evaluation for anyone interested. For reference, I've had 3 different tires in my car:
1. Michelin PS2
2. Pirelli Corsa (this is an R compound tire, not normal street tire)
3. Michelin Pilot Super Sport
4. (Next) Bridgestone RE 11
The PSS has been on my car since around 8/2011 - that's about 16,000 miles and it still has a lot of tread wear left. For comparison the PS2 rear was replaced at 12000 miles.
What to consider in a tire, for the enthusiasts?
1. Traction Self explanatory. More traction is better, but in general usually means shorter life.
2. Sidewall Stiffness (not talking about the rubber compound, but the *sidewall* construction)
Everyone knows about traction, the stickier the better of course; not frequently discussed is the importance of tire sidewall stiffness. The sidewall of a tire is a critical factor in suspension tuning; yes the tire is part of the suspension system and will affect body roll and weight transfer as much as stiffer springs! The tire therefore involves a trade-off, just like the rest of the suspension, and this trade-off again is about ride vs. handling. Stiffer tire is good for handling, but bad for comfort, and vice versa.
*Street tire tends to has soft sidewall, and therefore is more comfortable, but will also cause the car to lean more in corners.
*R comp tire (Michelin Cup, Pirelli Corsa, Toyo Roxes R888 - made for track, but legal on normal road) has stiff sidewall and will noticeably decreases body lean. The difference is significant and easily noticeable, a night and day change. These tires of course should not be used on wet road and are not as comfortable.
Tire Comparion Michelin PS2 vs. PSS
Comparison is difficult because there was a gap in between my usage of the 2. But to best of my memory, all IMHO:
1. Equal road noise, equal comfort between PS2 and PSS.
2. PSS has better dry traction (objective data, faster time at same track) per Michelin's claim, also per user's opinions, although this is obviously anecdotal and subjective.
3. PSS does seem to last forever - very true to Michelin claim. Remarkable for such a high performance tire to have such long tread wear and I believe best in industry (tirerack has tread wear rating for comparison, where PSS is among highest for hi-perf tire IIRC). I believe tread wear is where PSS is a game changer: everyone makes high performance tire, but to make it last so long and cost so little is where this tire shines.
4. PSS is about 10% heavier than PS2. 2-3 lbs per wheel. Increased unsprung weight means worse steering, handling, braking, accel., etc. Particularly bad at outer part of wheel, as in the tire. How important is 10%? Up to drivers.
5. In US, it's unheard of to have problems with warranty claim from using non N Michelin tire. I could be wrong but I would be shocked if there is such a confirmed case, based on non N tire alone.
6. PS2 is being phased out. If you have a non-fixable flat, finding replacement in future could be difficult.
7. PSS also has claim of special construction between inside and outside part of wheel for wet + dry handling. I believe wet performance is either very similar or might even be better per Michelin claim.
I think that all things considered, PSS is actually the better choice for reasons above. Basic tire construction doesn't change but the compound used in the construction of the tire has changed/improved and PSS has the newer technology (twaron, etc.). The only negative is the increased weight - about 2-3 lbs per weight, a touch disappointing since this is unsprung weight is at outer part of wheel, where it would cause the most harm to handling, steering, etc.
Tire Comparison R Comp (Pirelli Corsa) vs. Street Tires (Michelin PS2 and PSS)
General comments for those new to this: R comp tire is street legal, track oriented tire. They come standard in GT2 and GT3, as opposed to Turbo, which has street tire. R comp tire has 3 important characteristics:
1. The sidewall stiffness of R Comp's is significantly stiffer than street tires. Tirewall stiffness is critical because this is part of the overall suspension system. Tirewall stiffness is an integral part of suspension tuning and matching: stiffer tire means less leaning, less weight transfer.
2. The tire compound itself however is actually softer, wears much faster, and has significantly superior dry traction. The gain in dry traction is easily felt and utterly remarkable. It sticks like crazy glue and like magic. I was skeptical previously how much this gain is for amateur drivers - *NOT* anymore.
MHO: If you are nutty about motorsports, once in your life try R compound tire. This one should be on everyone's bucket list. :-)
3. Very poor wet traction and actually dangerous when it's wet. When it rains, all bets are off with these tires - you must slow down or better yet not driver at all IMHO.
4. When new, the Pirelli Corsa was reasonably quiet and not too stiff, but as the tire aged, it did become extreme noisy on freeway and was quite a bit stiffer.
I now have had Michelin PSS for 18 months or so and following is an updated evaluation for anyone interested. For reference, I've had 3 different tires in my car:
1. Michelin PS2
2. Pirelli Corsa (this is an R compound tire, not normal street tire)
3. Michelin Pilot Super Sport
4. (Next) Bridgestone RE 11
The PSS has been on my car since around 8/2011 - that's about 16,000 miles and it still has a lot of tread wear left. For comparison the PS2 rear was replaced at 12000 miles.
What to consider in a tire, for the enthusiasts?
1. Traction Self explanatory. More traction is better, but in general usually means shorter life.
2. Sidewall Stiffness (not talking about the rubber compound, but the *sidewall* construction)
Everyone knows about traction, the stickier the better of course; not frequently discussed is the importance of tire sidewall stiffness. The sidewall of a tire is a critical factor in suspension tuning; yes the tire is part of the suspension system and will affect body roll and weight transfer as much as stiffer springs! The tire therefore involves a trade-off, just like the rest of the suspension, and this trade-off again is about ride vs. handling. Stiffer tire is good for handling, but bad for comfort, and vice versa.
*Street tire tends to has soft sidewall, and therefore is more comfortable, but will also cause the car to lean more in corners.
*R comp tire (Michelin Cup, Pirelli Corsa, Toyo Roxes R888 - made for track, but legal on normal road) has stiff sidewall and will noticeably decreases body lean. The difference is significant and easily noticeable, a night and day change. These tires of course should not be used on wet road and are not as comfortable.
Tire Comparion Michelin PS2 vs. PSS
Comparison is difficult because there was a gap in between my usage of the 2. But to best of my memory, all IMHO:
1. Equal road noise, equal comfort between PS2 and PSS.
2. PSS has better dry traction (objective data, faster time at same track) per Michelin's claim, also per user's opinions, although this is obviously anecdotal and subjective.
3. PSS does seem to last forever - very true to Michelin claim. Remarkable for such a high performance tire to have such long tread wear and I believe best in industry (tirerack has tread wear rating for comparison, where PSS is among highest for hi-perf tire IIRC). I believe tread wear is where PSS is a game changer: everyone makes high performance tire, but to make it last so long and cost so little is where this tire shines.
4. PSS is about 10% heavier than PS2. 2-3 lbs per wheel. Increased unsprung weight means worse steering, handling, braking, accel., etc. Particularly bad at outer part of wheel, as in the tire. How important is 10%? Up to drivers.
5. In US, it's unheard of to have problems with warranty claim from using non N Michelin tire. I could be wrong but I would be shocked if there is such a confirmed case, based on non N tire alone.
6. PS2 is being phased out. If you have a non-fixable flat, finding replacement in future could be difficult.
7. PSS also has claim of special construction between inside and outside part of wheel for wet + dry handling. I believe wet performance is either very similar or might even be better per Michelin claim.
I think that all things considered, PSS is actually the better choice for reasons above. Basic tire construction doesn't change but the compound used in the construction of the tire has changed/improved and PSS has the newer technology (twaron, etc.). The only negative is the increased weight - about 2-3 lbs per weight, a touch disappointing since this is unsprung weight is at outer part of wheel, where it would cause the most harm to handling, steering, etc.
Tire Comparison R Comp (Pirelli Corsa) vs. Street Tires (Michelin PS2 and PSS)
General comments for those new to this: R comp tire is street legal, track oriented tire. They come standard in GT2 and GT3, as opposed to Turbo, which has street tire. R comp tire has 3 important characteristics:
1. The sidewall stiffness of R Comp's is significantly stiffer than street tires. Tirewall stiffness is critical because this is part of the overall suspension system. Tirewall stiffness is an integral part of suspension tuning and matching: stiffer tire means less leaning, less weight transfer.
2. The tire compound itself however is actually softer, wears much faster, and has significantly superior dry traction. The gain in dry traction is easily felt and utterly remarkable. It sticks like crazy glue and like magic. I was skeptical previously how much this gain is for amateur drivers - *NOT* anymore.
MHO: If you are nutty about motorsports, once in your life try R compound tire. This one should be on everyone's bucket list. :-)
3. Very poor wet traction and actually dangerous when it's wet. When it rains, all bets are off with these tires - you must slow down or better yet not driver at all IMHO.
4. When new, the Pirelli Corsa was reasonably quiet and not too stiff, but as the tire aged, it did become extreme noisy on freeway and was quite a bit stiffer.
#504
09-11-2013, 01:22 PM
^ Wow 20k eh? I hope mine do not last that long as I want to go to a softer compuound, or maybe R comp.
As far the the P-facility, looks awesome, I hope they open up the track to the public.
As far the the P-facility, looks awesome, I hope they open up the track to the public.
#505
09-11-2013, 01:24 PM
Are you going for 245's and 325's, or sticking with the stock sizing (235/305)?
The last set I purchased. I went with 245's & 305's. I would have done the 325's but they were out of stock.
The last set I purchased. I went with 245's & 305's. I would have done the 325's but they were out of stock.
#506
09-11-2013, 01:26 PM
EuroTom....your's will last longer because you don't drive your car enough!!!! 
Cheers!
#507
09-11-2013, 01:36 PM
HA HA HA HA Vid, so are you in a coaching mood or what? I need one that works for Beer and Lunch.
Regarding 325 in RE11, does it even exist? I've never seen that size availabe anywhere even though Bridgestone list it on their website.
#508
09-12-2013, 10:48 AM
Join Date: Dec 2006
Location: Palos Verdes
Posts: 3,116
Rep Power: 254
Vid,
Will remain strictly stock. BTW, Techart demo car also does what you did, but for them specifically to decrease understeer: wider width in front, rear width the same as stock.
Your perfectly done pics showing the difference between tire sizes always give me a chuckle. Porsche guys are all so OCD-good and OCD-funny (a compliment).
Will remain strictly stock. BTW, Techart demo car also does what you did, but for them specifically to decrease understeer: wider width in front, rear width the same as stock.
Your perfectly done pics showing the difference between tire sizes always give me a chuckle. Porsche guys are all so OCD-good and OCD-funny (a compliment).
Last edited by cannga; 09-12-2013 at 10:52 AM.
#509
09-12-2013, 11:01 AM
Join Date: Dec 2006
Location: Palos Verdes
Posts: 3,116
Rep Power: 254 But, if you want to shorten the life of your PSS, I am sure a few days at the track at typical crazy track speed will take care of that "problem" :-).
I suspect the Southern Cal center will be managed similarly to the one in Atlanta. Atlanta Porsche Center is *not* open to public, non-DE events, is it?
#510
09-12-2013, 12:15 PM
Can,
I have a set of RE-11s and getting a set of R888s. I have a similiar alignment as you in terms of camber. I'm feeling I need more. I corded my H6s with such a minimal camber. I was going to try and get -2, I have techart springs. Should I be able to get close -2 without camber plates and adjustable arms and such?
I will leave the backs in -1.5 range
I have a set of RE-11s and getting a set of R888s. I have a similiar alignment as you in terms of camber. I'm feeling I need more. I corded my H6s with such a minimal camber. I was going to try and get -2, I have techart springs. Should I be able to get close -2 without camber plates and adjustable arms and such?
I will leave the backs in -1.5 range