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Hello, these tires are Continental Extreme Contact Sports with 9 track days and the outer edges are taking a beating. The suspension is pretty much maxed out at -1 degrees of camber with just a touch of toe since it is mostly a street car. Start the day with the tires at the recommended 30 psi and bleed down to 35 hot. Planning on trying 37 next time but that may not be until Spring. What are others using in the blue group? 20191001_191012.jpg 20191001_191012.jpg
 

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Better tires. Continental tires have hideously soft sidewalls that you will roll onto all day.

If you want a good daily / track tire, Michelin PS4S. But if you're frequently tracking, I'd strongly recommend investing in another set of dedicate track wheels with UHP or racing tires.

That being said, you could definitely use more camber. -1° is nothing. My C30 has -2° from the factory.
I've found -2.5° front and -2.3° rear to be about the sweet spot on my 987. Slight toe-in on the rear and straight up front. Damping is fairly soft up front and the rears are dialed in a tad firmer.

30psi also seems pretty low for a cold tire. I usually start at 35psi and adjust as necessary after each session. But tire pressure is more based off of preference, track conditions, temperature, and driver habits. So you'll need to find something that works best for you.
 

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Adding pressure, esp if you're already starting at factory specs, is generally not the direction to go.

Tire wear is a combination of camber, tire pressure, track conditions, and temperature. Camber and track are probably the biggest factors in wear. Some tracks are harder on tires than other tracks. With factory LCAs, the pics of your tires are probably typical. Your next step would be GT3 LCAs. But regardless of what steps you take, tire wear is a fact of life when doing DEs. Looks like you have another 1-3 days left on those, which is typical of street tires (10-12 days).

I have an 08 Cayman S Sport. Factory specs on pressure are 32 frt, 37 rear. I have my camber set to -2.3 frt, -2.0 rear. I just went to -2.3 frt from -2.5 as I wanted less inside wear. I had Conti Extremes for several yrs but just bought a set of Yokos that I used for the 1st time at Indy in Aug. Here's what I've learned about street tire pressures that works for me:

I start in the morning setting my cold tires at 3 lbs under factor specs (29, 34). After the session, I set the hot pressures to 3 lbs over factory specs (35, 40). I keep them at the 3 over throughout the rest of the day. Pressures go up throughout the day as ambient and track temp goes up and I release pressure accordingly after each session. By the end of the day and the tires cooled off, they could be down by as much as 7 lbs. Your TPMS is not going to be your friend, esp if there's a long time between sessions. At Indy, it's 2 hrs between sessions. I started the last session with semi-cooled off tires with my TPMS telling me I had a flat tire because of the 7 lbs under spec.

How do you know what's the right pressure? Your tires tell you during a session. If your car starts off handling well, but somewhere along the line it starts to push and the tires are howling, you have too much air. Drop the pressure after the session. If your car is pushing half way thru the session, drop 2 lbs. If it's 3/4 of the way thru before handling goes away, drop 1 lb. Find the pressures that keep your car handling well thru the whole session and then use those #s as your baseline the rest of the day.

My 1st run of the day is generally a throw-away session. My tires are cold and the track is too. Probably not going to set any lap records. Good time to hone in on what your car is telling you. As I said earlier, I start the 1st session 3 lbs under. It usually goes half way thru the session before the handling turns to push. After the session, the pressures are usually 37 & 42. I drop 2 lbs and I'm ready to attack the 2nd session - I have my tires at the proper pressures and the track is at optimal temp. As the day and track warms up, I chase it with dropping pressures (usually 1 lb at a time) the rest of the day.

But rounding back to your original ques, tire pressure will have less to do with outside tire wear than camber. If you want to address the wear, GT3 LCAs are your next step. Tire pressure affects handling more than anything.
 

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^ Great points! Should also mention that you're talking about air in the tires and not nitrogen.
 

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FWIW, also have a 2008 CS (Midnight Blue). Door jam tire pressure table states 30 Front and 37 Rear. Running Mich PS4S. Was advised by experienced trackers to start at 30/30 with the goal of finishing sessions at 34/34, measured as soon as exit track. I find pressures exceeding 34 after every session, especially on hot days at the track, as they all are here in FLA! Over the course of a day the rear tires will have had the original 7 lbs bled off to start, then up to 8 additional lbs. Best recollection is we drove to the hotel afterwards and inflated the tires first AM the next day, all were at ~22 lbs.

Performance-wise, I ran my best times at 34 psi hot and have stuck with it since. No issues with unusual tire wear.

Sorry I cannot speak to exact camber settings, would need to speak to the indy shop. Rear tires do wear more on inside due to the camber being adjusted for autocross and DE.
 

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Hmm, my spec cold pressures are 30 front 31 rear on my '11 2.9 Cayman with 18 s wheels...
Any case, for me I run 34-36psi hot all around. Generally will have to bleed down a couple of times as I don't like to go out on cold pressures less than 26psi, or 24psi for the tire that sees the most pressure rise (outside rear for me/my car).

Anyway, yeah, you need more front camber. I went the $$$ way and got GT3 control arms for -3 up front. That will give more front grip and make much better use of the front tires. Or camber plates could be another option, I don't think they give as much camber but they are less $$$
Short of that you could flip the tires on the wheels to share the punishment with the inside shoulders that have had an easy time this year...
 

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Short of that you could flip the tires on the wheels to share the punishment with the inside shoulders that have had an easy time this year...
Some of the new / modern tires don't allow you to swap them inside out. They may have a designation on the sidewall specifying one side MUST be on the outside. This is because tire companies have begun using different compounds across the tread, with harder compounds on the outside edge of the tire to help them resist wearing out. If the tire says OUTSIDE on one of the sidewalls, it can't be swapped to the inside. However, some modern tires do allow you to swap them from left to right, ie, they're not unidirectional. If you're at a track that is hard on left tires, you may be able to swap them with the rights to get more wear from the set.

BTW... I have 19" tires on my CSS. That's why I listed my tire pressure specs - because there are 18" wheels available and Porsche changed the pressures for the 987.2. If you want to use my system, just remember starting at 3 lbs under cold and then staying at 3 lbs over hot.
 

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Some of the new / modern tires don't allow you to swap them inside out. They may have a designation on the sidewall specifying one side MUST be on the outside. This is because tire companies have begun using different compounds across the tread, with harder compounds on the outside edge of the tire to help them resist wearing out. If the tire says OUTSIDE on one of the sidewalls, it can't be swapped to the inside. However, some modern tires do allow you to swap them from left to right, ie, they're not unidirectional. If you're at a track that is hard on left tires, you may be able to swap them with the rights to get more wear from the set.
Asymmetric tread patterns aren't new, which have the same "outside" markings for the intended tire orientation. The Continental ExtremeContact Sports OP has are like this. Dunno about the compound across the tread. However nothing catastrophic or even noticeably bad will happen if you flip these tires inside to outside at about halfway through their lives. Likewise even if the "outside" compound is softer/grippier vs. "inside", it's not going to be the end of the world to flip them to get a couple/few more events out of tires if you're camber-challenged.
Flipping asymmetric tires on the wheels requires dismounting and remounting, though, so the time/hassle/$$$ of that should be weighed against just getting new tires which you'll have to do soon anyway...

Similarly, unidirectional tires can be run "backwards". Tests of backwards-mounted unidirectional tires in wet conditions have been performed multiple times over the years and differences in grip and hydroplaning resistance have always been minimal to nonexistent. I've run unidirectional backwards a bunch of times at the track, including in the wet.

BTW... I have 19" tires on my CSS. That's why I listed my tire pressure specs - because there are 18" wheels available and Porsche changed the pressures for the 987.2. If you want to use my system, just remember starting at 3 lbs under cold and then staying at 3 lbs over hot.
Interesting, I have to say I'm surprised that the front/rear specs are 5psi apart! Given larger higher-load-capacity tires in back, I'm surprised they spec that much more rear pressure. It's worth considering whether or not 987.2 pressures should supersede 987.1 specs...
Fortunately most radial tires are somewhat tolerant and stable over a fairly broad range of pressures.
I'm beginning to run into people in an apparent "race to the bottom" to see how LOW they can go with pressures, which seems misguided and potentially dangerous to me... But 40psi hot may be on the high side...
But maybe spec +/-X psi isn't a bad approach...
 

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NYPcar- Find a really good suspension shop that can give you -2.7f and -2.1r. GT3 lower control arms for the front and the max oem camber in the rear. As others said, toe at 0 f and toe in 12 minutes r. You will find that the total tire wear is caused from track use, not daily driving, so think about your next set of tires that can be reversed so your shoulders will even out. Just do not core them before shoulder flipping .

I have sets of Hoosiers, RE71R's and Michelin MP4's. The daily drivers need to be quiet, which the Michelin's are. They seem to have a great balance of turn in response, braking in the wet, and wet traction. If track wheels and tires are needed then Titan 7 T-S5's monoblock Forged and RE71R's 255/35/18 f and 275/35/18 r's would do the trick due to their stiff sidewalls, which can withstand lower pressures when called for. About $3000.
 
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