off topic: you missed a great DE in Savannah. We had four new GT3RSs at the track. Absolutely sick!!!!! My car did great and was turning consistent laps and the R888s did very well at 36/38 hot. It even looked like I could dial in a bit more negative camber in the rear (maybe bring it to -2.0 from -1.8) based on the wear patterns.

 

Dumb Question...... Besides the camber issue, would purchasing "Heat Cycling" when I got the tires help prevented this, or is that something different.

 

Usually heat cycling is for a DOT specific tire so you can go right out and "tear the track up!" You can get more life out of a track tire that way or you can heat cycle them your self and save a few bucks.

If you plan on doing more DEs then I would get a spare set of wheels and put on track rubber and save your street tires the abuse!

 

Ahh glad you had a blast! The R888's work perfectly for a DE tire and on our heavier cars. I just took off my RA1's and am going back to new manufacture date R888's.

What camber and toe are you running front and rear?

Also when I ran R888's I found that no more than 37 hot in the rear worked for me and the center of the tire did not wear as fast. 38-39 wore out the center on the R888. I could run 38 hot no problem with my RA1's but the RA1 has a softer sidewall too than the R888. For Sebring I ran R888's at 35/36 hot mostly. For Daytona I ran higher on right side than left side...but that's the way Daytona is due to the banking. Different tracks require different set ups.

 

+1 on buying a set of rims for the track, like OZ Allegerita (sp?) for ~$1500, then fit them with something like the R888s mentioned above. If you buy the right tire, you can even drive them to/from track if that's what you need to do.

One more thing about your tire wear, though. From the sounds of it, and the looks of it, in addition to probably having an issue with rear camber, you may also have an issue with your sway bar settings. To me, the sway bars are mainly for adjusting the cars bias to understeer/ oversteer. Your tires (and your posts) indicate to me that your car is biased to oversteer, putting excessive wear on the rear tires. To adjust that, you should either stiffen the front or soften the rear, or some combo of both. Adjusting tire pressures f/r can also help, ie relatively more up front and less in the rear, but you don't want to get outside of the ideal range for the tire, and pressures will only do so much. Sways are more helpful for that.

Hope that helps

 

Jack....I appreciate your (and others') input. What you describe sounds consistent with what I am doing, which speaks volumes about your knowledge considering my description. You clearly know much about camber, alignments, and sway bars, etc. If you please, where does one gain knowledge about such elements. I explored youtube but got many on not-too-helpful videos. Once on-track, I basically started moving my front sway bars one bolt-spacing every session to see what would happen!

I really want to know specifics, it's just hard when I go to my dealer (or wherever) for alignments and they say.... "we set you up aggressive"..... Whatever they translate that to mean...

 

Glad it's appreciated. Thanks for that - it makes all that thinking and typing worthwhile.
Most of my knowledge comes from:
- 10 years of reading these boards, mostly Rennlist
- 10 years of chatting with mechanics, other drivers, vendors, etc, while enjoying the track hobby
- experience driving on the track (10 years, DE and club racing)
- a bit of reading books

I'd recommend the following:
- Skip Barber: Going Faster (Basics of Track Driving, great for beginners)
- Carrol Smith: Tune to Win (This one should have more of the tuning. I can't find my copy to confirm, but I did find my copies of Drive to Win and Think to Win. His style gets a bit old, but I think Tune to Win would be worth it for you)
- Mark Donohue: The Unfair Advantage (Awesome book, more of a biography, but has some great info on driving, car setup, etc. From a technical perspective, the section on Friction Circle is worth the price of the book, but it is so much more than that.)
- Ross Bentley: Speed Secrets/Inner Speed Secrets (Interesting alternate way to think about track driving)
- Also, the on-line stuff on Rennlist Racing & DE can be very, very good, but you need to be able to parse through some crap. Try the search function. One guy who I usually like over there is SundayDriver. You can do an advanced search and find his posts in that sub-forum, then search on interesting titles and you'll usually find some good dialogue. (Sorry to admin here if it's not cool to talk so much about another forum, but I'm not familiar with much here yet)

One other thing that I didn't get to post about your car set-up: you might not need more adjustments on the sways until you sort out the alignment. If the alignment gets you the proper contact patch in the rear, you might not have that oversteer bias anymore. However, once you're at the track, the sways are easier to adjust on your own, compared to the alignment stuff.

 

I doubt it is a sway bar setting. Especially since the sways on his car are not adjustable. I did a year of DE's on street tires and had zero issues other than wearing out the outside corners as I got faster due to lack of camber. I see some street tires at my track days just really chewed up and it is usually do to the balance of the car not correct in the corners due to over driving and not a smooth driver.

+1 on alignment settings. Seems like his toe and camber is possibly way off too. For a stock suspension 997S the best he will be able to do in the front is -1 degrees of camber but the toe needs to be set at zero or no more than .02 degrees. The rear needs to be kept with in .5 of a degree of the front so if he can get -1 in front -1.5 or at most -1.7 in the rear with a toe setting of .12 to .14...no more... will greatly help not only turn in but street and track tire wear will greatly be improved.

 

yup - I even added some more comments about alignment in my last post, stating that sway bar settings might not need to be adjusted if he just gets the right camber and other alignment settings. I think he did say that he upgraded front and rear sways to adjustable ones, btw.

 

I'll chime in and confirm what others have said about alignment.

I'll add that I recommend you get a set of GT3 lower control arms (or the RSS units) and some solid rear toe links. There are bare minimum for someone who tracks a fair bit and don't affect ride quality at all.

 

Also, when I started tracking I ruined a brand new set of PS2s on my first day. Street tire just don't hold up to aggressive drivers. I know people are going to tell you that moving to an r comp is t good for starters but I believe that there are exceptions to the rules.

Just like brake pads, tires have an optimal temperature range. An agressive driver will heat up street tires and wreck them quickly. Hoosiers (which are WAY over kill at this point) have an optimal operating temperature of about 180-220 degrees! Imagine what would happen to any street tire if you got them that hot. I'm reasonably confidant that you over heated those street tires and that's why they split.

Now, on the flip side, I was over heating fronts my first day not because I was good but rather because I didn't understand the car. I was over driving it and ploughing through corners. I was fast, but limited. And I couldn't afford to eat tires like that!

My point is that even once the car is well setup, you need to continue to learn about the physics and dynamics of the car. I went back to stock for my last track day and my tire wear was almost perfect and even and the car handled pretty darn good. I could induce over or under steer with the throttle and that's pretty good with a stock setup.

Have fun!

 

Actually my sways are adjustable, front & rear. Have the TPC racing sways, installed after a DE earlier this year when I noticed my S rolling more than I'd prefer through chicane's.

I certainly could be overdriving as I definitely plow/ understeer in a reducing radius coming out of a carousel and another sharp turn onto the oval (where i've been tracking lately).

Like I said, I really don't know much about the sway adjustments and was simply experimenting in between sessions to see if it would modify the understeer. I can run pretty consistent laps and still could not tell much of a difference between the settings.

One thing I mentioned way earlier however was that I really chewed up the tires after the first session (20 min) on new tires with factory sways. After my last session on the most recent DE the tires developed this strange seam.

I planned on junking the tires after this (probably last) DE for the season and hoped they would hold and "drove the **** out of them". By the way, I was driving the quickest laps I have ever driven last weekend, so something must be working, maybe at the expense of my tires?

Hence, my original question; were my Pirelli P Zeros just not up to the task, am I driving hard on them that no tire would stand up to this, or is it what many of you are saying that my alignment/ camber/ sways are just not set up ideally. Probably a combination of all of the above?

I'll look up the books/ videos suggested.......Thx.

 

Re the original question, there are some things that are certain and some that are possibilities. The certain thing (or atleast a consensus of internet 'experts', always take that with a grain of salt ) is that your alignment is off. That addresses the wear on the rear more than the seam on the front. PZeros aren't going to hold up like track tires, as a few have mentioned above, so that answers most of your question, I believe.

Re the books/videos, I was referring only to books. Not sure if someone else referenced a video. I do know that Going Faster is available in a book and a video, but the video is not so good. Get the book.

 

Roebling Road is harder on the left side tires so i had - 2.5 on the left and - 2.2 on the right. Both rears were at about 1.8-1.9. I was watching the sidewall wear indicators and the scubbing and once I got the rears to 38 it was good. Any less then the wear was to far towards the sidewall. I may post pics. I'm thinking of going -2.5 both fronts and -2.0 rears and that should be good. I've deen DEing since 1995 and instructing since 1998 so i do drive the car hard so I want to milk the tires for all they are worth!!! The car is strictly a weekend driver when not on the track. I did one flip from side to side to even the wear over the 2 days which was easy and quick.

I do have the H&R springs sitting the the box in the garage and wanted to wait to install after I had a DE under my belt in a bone stock car. I think that will reduce the roll a little and settle the car faster between turns. Your input on the springs???

 

Hi Doc, you must have put on GT3 lower control arms to get anything more than -1 camber up front. Are you on 18 or 19" wheels?

I do not have much of any input on springs because I've never run them on a stock PASM set up. My 09 has the lowered Sport PASM and to me it is much better than the stock PASM...that is the only comparison I have. I've taught students in 997's with aftermarket springs that lowered the car and in that beginning student setting I did not feel anything bad on the track.