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      03-20-2012, 09:41 AM   #485
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Quote:
Originally Posted by CanAutM3 View Post
This is also what I understood.

I am still puzzled by the physics of this: How can putting a tire with more grip in the front increase understeer ?
Perhaps "stability" means slow to change direction, however, the rear tire design still has a high level of ultimate grip? With the variable tread compound design I wonder if they don't use the "softest" compound (or smaller width) on the outer tread blocks - this would slow down turn in (give the feeling of "stability") but then as you continue to load the tire it's still capable of generating a high level of lateral grip.
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      03-20-2012, 09:46 AM   #486
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Quote:
Originally Posted by CanAutM3 View Post
Agree on what you stated: Load the front to get more grip.

But how would installing a front tire with less grip help?
One theory - when you use wider tires, in effect your contact patch widens. Under same load conditions theoretically the contact patch actually stays the same between tire widths. So instead of a square contact patch you have an elongated contact patch which will affect the turning characteristics.

During my turn-ins at the track I generally stay on the brake a little longer (trail brake) and add some steering input before I fully release the brake initiating some rotation to get things going.

Driving on the track is much different than on he street as you approach the limits
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      03-20-2012, 09:46 AM   #487
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Quote:
Originally Posted by dbarnes View Post
Perhaps "stability" means slow to change direction, however, the rear tire design still has a high level of ultimate grip? With the variable tread compound design I wonder if they don't use the "softest" compound (or smaller width) on the outer tread blocks - this would slow down turn in (give the feeling of "stability") but then as you continue to load the tire it's still capable of generating a high level of lateral grip.
Gotcha, makes sense. So we are not talking about steady state understeer but more like less turn-in response.
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      03-20-2012, 09:48 AM   #488
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Quote:
Originally Posted by 4sevens.com View Post
Driving on the track is much different than on he street as you approach the limits
Agreed .
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      03-20-2012, 09:52 AM   #489
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Quote:
Originally Posted by CanAutM3 View Post
Gotcha, makes sense. So we are not talking about steady state understeer but more like less turn-in response.
That's what I get out of the email. It sounds like if you use a tire designed for the rear on the front you'll get understeer at initial turn-in but it has nothing to do with steady-state and/or mid-corner handling/grip.
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      03-20-2012, 10:00 AM   #490
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Quote:
Originally Posted by dbarnes View Post
That's what I get out of the email. It sounds like if you use a tire designed for the rear on the front you'll get understeer at initial turn-in but it has nothing to do with steady-state and/or mid-corner handling/grip.
So my conclusion, more front end grip with wider and stickier PSS tires up front is still better for quick lap times. However, this would decrease turn-in response. This could be compensated through adapting driving style (as mentioned by 4sevens) or by adjusting the suspension (camber and/or toe).

Am I correct?
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      03-20-2012, 10:04 AM   #491
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Quote:
Originally Posted by CanAutM3 View Post
So my conclusion, more front end grip with wider and stickier PSS tires up front is still better for quick lap times. However, this would decrease turn-in response. This could be compensated through adapting driving style (as mentioned by 4sevens) or by adjusting the suspension (camber and/or toe).

Am I correct?
I had GC camber plates installed and dialed in -3.0 -2.0 front/rear and the car is a completely different now. Initial turn-in is more crisp and the outer shoulder isn't tearing up anymore.
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      03-20-2012, 10:18 AM   #492
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can you use camber plates with stock suspension?
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      03-20-2012, 10:19 AM   #493
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Quote:
Originally Posted by chriszeh View Post
can you use camber plates with stock suspension?
You can with GC plates. Though I opted for their springs which was only a couple bucks. Linear vs progressive makes a difference with steering response but adds nvh
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      03-20-2012, 10:27 AM   #494
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Quote:
Originally Posted by CanAutM3 View Post
So my conclusion, more front end grip with wider and stickier PSS tires up front is still better for quick lap times. However, this would decrease turn-in response. This could be compensated through adapting driving style (as mentioned by 4sevens) or by adjusting the suspension (camber and/or toe).

Am I correct?
If you change "wider and sticker" with "rear-axle designed" then, yes, I agree. For example, if you use a wider and sticker front-axle designed tire on the front then I don't think you'll run into the same understeer issue the Michelin engineer was describing in the email.

Now on my old e46 M3 I did notice if I used a staggered PSC setup the front end would turn in a bit quicker than when I used a square PSC setup. However, overall lap times were lower with the square setup.
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      03-20-2012, 10:27 AM   #495
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Quote:
Originally Posted by chriszeh View Post
can you use camber plates with stock suspension?
I am running GC camber plate with stock EDC suspension. Greatly improved the handling and tire wear .
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      03-29-2012, 04:05 PM   #496
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what sized tire do you guys recommend for 18 inch volk te37 with +22 offset all around? i was thinking about 265/35 front and 285/25 rear...
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      03-29-2012, 06:22 PM   #497
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http://www.tirerack.com/tires/TireSe...=54350&tab=All

I need to replace the OEM PS2 tires that came on my car finally (been running winters during the cold months). But, as you can see in that link, tirerack won't have my size until mid-May at best. Anywhere else I can get OEM 18 inch sized PSS? Or should I just call up some local places?
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      03-29-2012, 08:05 PM   #498
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Quote:
Originally Posted by 4sevens.com View Post
I had GC camber plates installed and dialed in -3.0 -2.0 front/rear and the car is a completely different now. Initial turn-in is more crisp and the outer shoulder isn't tearing up anymore.
+1
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      03-29-2012, 08:18 PM   #499
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^ I just inspected the tread on all 4 and it's very evenly worn after about 3k miles and a few track days. Keep in mind this will vary with your driving style and the size and type of rubber you run as well as the pressure you have in them.
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      03-29-2012, 09:35 PM   #500
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Quote:
Originally Posted by 4sevens.com View Post
^ I just inspected the tread on all 4 and it's very evenly worn after about 3k miles and a few track days. Keep in mind this will vary with your driving style and the size and type of rubber you run as well as the pressure you have in them.
I run a dedicated set of track wheels and tires so I do see slightly more wear on the inside of my PSS street tires with the increased camber. It is barely worth mentioning though and definitely worth the handling and tire wear advantages on the track.
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      03-29-2012, 09:39 PM   #501
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Quote:
Originally Posted by CanAutM3 View Post
I run a dedicated set of track wheels and tires so I do see slightly more wear on the inside of my PSS street tires with the increased camber. It is barely worth mentioning though and definitely worth the handling and tire wear advantages on the track.
Are you on 18's or 19's?

I ran 18's and the wear was terrible everywhere... outside chunked, inside worn, the middle tread was worn to an angle.

For some reason the 19's are wearing so much better. completely even.

I'm using PSS's for both street and track. Sometimes I throw on a set of slicks on my 18's
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      03-30-2012, 01:59 AM   #502
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Quote:
Originally Posted by OC3 View Post
+1
Agreed.
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      03-30-2012, 07:01 AM   #503
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Quote:
Originally Posted by 4sevens.com View Post
Are you on 18's or 19's?

I ran 18's and the wear was terrible everywhere... outside chunked, inside worn, the middle tread was worn to an angle.

For some reason the 19's are wearing so much better. completely even.

I'm using PSS's for both street and track. Sometimes I throw on a set of slicks on my 18's
I run the 19" 220M wheels on the street with 255/35 and 275/35 PSS. For the track I use square 275/35 Nitto NT01s on 18"x10" rims. The wear on my track tires is pretty good. Since I am only using my PSS on the street, I do see a very slight increased wear on the inside of tires due to the increased camber. I guess if I were to run them on the track, the uneven wear would be offset by the greater cornering at the track. But like I said previously, the uneven wear is very light, in the range of 1 to 2/32" inside to outside, a little worse at the rear. Nothing to fuss about .

Last edited by CanAutM3; 03-30-2012 at 07:30 AM..
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      04-28-2012, 12:53 PM   #504
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TEASER!
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      04-29-2012, 02:13 AM   #505
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Quote:
Originally Posted by naterater View Post
TEASER!
I don't see what this could be a teaser for unless you got a PSS 285/30/19 on your wheel! Lol
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      04-29-2012, 12:51 PM   #506
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Quote:
Originally Posted by Jrollsp View Post
I don't see what this could be a teaser for unless you got a PSS 285/30/19 on your wheel! Lol
Well you don't know what they are going on... Plus, unless you know that only 1 version of the Alufelgen wheels come stamped, you don't know what version it is.

So here is a little bit more, working on getting some better ones.

Last edited by naterater; 04-29-2012 at 12:56 PM..
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