Cannga, do you know the Damptronic spring rate or difference for a 2011-2012 Carrera GTS than Turbo, Carrera etc?

I had my local shop install Damptronics on my 2012 Carrera GTS late last year. I like them...seem to be a good compromise for street/track and plus I could corner balance my car too.

I looked but could't find a GTS based Damptronic package but my shop said a Turbo or Carrera S or GT3 Damptronic package would not work and they had to find the Carrera GTS model.

 

Tire Update

I now have had 4 popular tires in my Turbo and following is an updated evaluation for anyone interested:
1. Michelin PS2 (rear lasted about 12k miles)
2. Pirelli Corsa (this is an R compound tire, not normal street tire, lasted about 1 year/10k miles both front and rear)
3. Michelin Pilot Super Sport (lasted about 2 years, from 8/2011 to 2013, 20k miles!)
4. Bridgestone RE 11


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.


Tire Comparison Bridgestone RE 11 vs. Michelin PS2 and PSS
RE11 is stiffer than PSS, about 1/2 way between PSS and cup tire with respect to stiffness. The stiffness reduces ride comfort but makes handling and steering so much more precise and fun. Body roll is reducing noticeably compared to PSS. The key is that the reduction in body roll makes the car corners as if it is on rails. This is the best my car has ever felt when it comes to steering and handling, short of the Pirelli Corsa cup tire (which I don't want to use because it is so dangerous on wet roads). Really the car corners beautifully with these babies.

Road noise is about same between RE 11 and PSS. Traction is close enough that without instrumented, professional-level testing, I doubt I could ever tell a difference. Wear: I don't expect RE11 to last nearly as long as PSS, which IMHO is a game changer with respect to performance tire: 20k miles in my Turbo - unprecedented.

Before you run out and order these tires, please note my bias: I place handling above all so I tend to sacrifice comfort a little more than normal people . I also live in a hilly/mountainous area so body roll has to be minimized for my taste. If you find yourself with same preference, I would recommend them without hesitation. I think of RE 11 as cup tire with less dry traction, but without the wet road danger ;-). Cheaper, sporty, SO MUCH fun!

 

I do not know the answer, but I think the following 2 sources would be of help:

1. Call Bilstein USA in California. This is how I find spring rates of my Bilstein.
ThyssenKrupp Bilstein of America
14102 Stowe Drive
Poway, CA. 92064
1-858-386-5900
2. AWE Tuning - these guys are true experts when it comes to anything Bilstein: 888-565-225.
http://www.awe-tuning.com/

Is something not to your liking?

 

Cannga, Glad to hear you are enjoying your new RE's! Did you go for the 245/35 & 325/30 combo or did you stick to OEM spec 235/35 & 305/30's?

 

Can are these Re11a's? I noticed on tire rack the treadwear rating changed to 200 from 180 however they're not listing them as -A's

 

Thanks..I just wanted to know....I'm liking the Bilstein Damptronocs on my car.
Speaking of RE11...I was looking at specs between various tires and RE11's are about if not the heaviest tire.

 

Can: Absolutely love your car! Sorry if perhaps a little off topic but would you mind sharing more pics? Would love to see the sand interior too, so far it seems we only got a peak (GIAC module).

Thanks!

 

You shopping for a P-car kaiv?? Still tracking your M3?

 

Thanks for the nice comment. You have an M3? Just this year I got one for the wife. I *ABSOLUTELY* love the V8 engine, and to my surprise, above all, the steering of the M3. Different from Porsche, and yet "better" in some way.

I deleted some pics from first page of this thread accidentally and just repost them. Interior is very boring really: nothing spectacular, just the typical monotonous Porsche sand beige. Exterior I humbly agree, the Turbo is a very very pretty car no matter how often you look at it.

For shutterbug fans: First shot is Canon 1D with Canon 85 1.2. Second shot is Nikon D80 and 60mm 2.8. Both shot in raw and developed with Capture One. I've always been a Canon shooter but recently tried out Nikon so I could test the tremendous Nikon for my travel pictures.

 

Yes very much so and thanks to the long running thread of yours that keeps nagging and nagging on me . I stayed with OEM spec.

The sidewall says "RE11" so I assume it is not the A; I am asking my tire dealer to confirm which one it is. Do you know how the 2 versions are different?

You are welcome. Yes it comes to weight: Bridge RE11 > Mich PS2 > Mich PSS > Cup tires (I listed the weights in the tire index on first page of this thread for anyone curious). But the reduction in body roll and improved cornering is so significant that I very likely will stay with RE11 from now on.
Weight gain is that last thing you want in a sports car, let alone unsprung weight, but to be honest it is difficult for me to tell the difference, perhaps because of the "sequential" nature of a typical tire switch. Would LOVE to do instant A/B comparison of 2 identical cars with slightly different tire weight!

 

It looks like the 11A ranges in size from 15-18 and the 11 (non-A) ranges in size from 16-19. "Sharing the tread design of the popular Potenza RE-11, the Potenza RE-11A adds an exclusive tread compound that combines silica with a new long-link carbon black to increase road contact and abrasion resistance while promoting tread rubber flexibility across a range of cool to hot temperatures". - from Tire Rack

 

lol not really, I just have a bad case of forum addiction. I lurk in a few places including here, rennlist and corvetteforums

Sold the E92, got an E36 in which I'm rebuilding and swapping an S54 right now. Should make for a fun track car!!



Can> thanks for the reply!
The S65 V8 in the M3 really is a gem! I kinda wish they had put it in a lighter and sportier platform. The car is fantastic but too much of a compromise it seems. On one hand it's not sporty/racy enough in stock form and on the other hand not GT enough either. The 997 turbo feels like twice the car really!

 

Sounds like a lot of work! Best of luck getting that done and hope to see it at the track soon!

 

Those are some nice shots! Very good looking car

 

Good info. Now I still have a question about treadwear. If i remember correctly the RE-11's used to be @ 180, now they're 200, when did this change? The new -A version is 200.