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This is sort of a rehash of some previous posts but I'm trying get more specific. I know GT-R sized tires in the PSS come out next Spring but...

I don't like how the lower profile 285/30-20 look nor the speedo difference.

However these seem more in line with OEM:

275/35ZR20 - 755 revs per mile - 27.6" height - Reinforced & 300 AAA
295/35ZR20 - 740 revs per mile - 28.1" height - Not Reinforced and come in two versions 220 AAA & 300 AAA

1.99%/2.02% difference is revs per mile. Not too much. I wish the 295s would fit on the fronts.

According to this:
http://www.tirerack....kwall&tab=Sizes
the 275s are reinforced but the 295s aren't, plus the 295s come in a 300AAA and 220AAA...

My first question...is the .6" height difference from front to back going to be an issue on the street or the track?
If having runflats up front vs non-rfts in back a problem?
Is having 300AAA up front and 220AAA in back a problem?
Some who have tested this tire used the Ferrari speced ones(even in 300AAA). Has anyone used the "generic" ones? Differences?

These are a MUCH cheaper tire vs any of the OEM options. I don't know of any other tires that can offer good track performance for a good price either. I tried R888s and they aren't that good really.
 

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Why you didn't like the r888? It's a real compound .

I that Michelin the one that the corvette did its record on ?
 

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R888 is noisy

Corvette is using another tire which is considered to be a semi slick

RF is reinforced not run flat

As I recall 0.5" is the limit

Dunno if it work, worse case scenario you take the 295 off and install 275s in the back
 

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R888 is noisy

Corvette is using another tire which is considered to be a semi slick

RF is reinforced not run flat

As I recall 0.5" is the limit

Dunno if it work, worse case scenario you take the 295 off and install 275s in the back
Ahhh RF = reinforced. Thanks!

Yeah R888s were noisy but comfy but the worst part is their longevity on the track. At first they are good but they go downhill after the first couple sessions. With a lot of tread left they are as slippery as snot...the OEM Dunlops aren't so much.

Ok well I read 0.6" was the limit, but I worry that since wear rates on the track are greater up front than in the rear this difference will increase over time.
 

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I really wish they would make them in a 265/40/20, that would be a perfect match for the 295/35/20's.
 

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Discussion Starter · #6 ·
I found this post from December 10th on a BMW M% site regarding the new sizes coming out:

Michelin will be expanding their Pilot Super Sport size lineup in the middle of the first quarter of 2012.

I will provide more details on availability and pricing as they become available.

here's the new sizes for 2012

205/45ZR17 (88Y) XL
245/45ZR17 (99Y) XL

205/40ZR18 (86Y) XL
215/40ZR18 (89Y) XL
235/50ZR18 (101Y) XL
245/35ZR18 (92Y) XL

255/30ZR19 (91Y) XL
255/40ZR19 (100Y) XL
255/45ZR19 (104Y) XL
275/40ZR19 (105Y) XL
285/40ZR19 (107Y) XL
325/30ZR19 (105Y) XL
345/30ZR19 (109Y) XL

245/45ZR20 (103Y) XL
255/40ZR20 (101Y) XL
255/45ZR20 (105Y) XL
265/30ZR20 (94Y) XL
285/35ZR20 (104Y) XL
335/30ZR20 (108Y) XL
 

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Above about 12mm front to rear, the AWD system might go into fail safe.

From the service manual.

DIS-TIRE MONI
Vehicle running with normal size tire installed 0 - 4 mm
Vehicle running with improper size tire installed (Front/rear tire size
difference, wear condition) 4 - 8 mm, 8 - mm

Fail-Safe (GT-R certified NISSAN dealer) AWD system

• If any malfunction occurs in AWD electrical system, and control unit detects the malfunction, AWD warning
lamp on combination meter turns ON to indicate system malfunction
• AWD system activates its protection function (shuts down AWD system temporarily) if AWD system detects
high load continuously or the front wheel tire size differs from the rear tire size. (AWD system is automatically
restored if AWD system no longer detects any overload or the tire size difference is eliminated.)
 

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Above about 12mm front to rear, the AWD system might go into fail safe.

From the service manual.

DIS-TIRE MONI
Vehicle running with normal size tire installed 0 - 4 mm
Vehicle running with improper size tire installed (Front/rear tire size
difference, wear condition) 4 - 8 mm, 8 - mm

Fail-Safe (GT-R certified NISSAN dealer) AWD system

• If any malfunction occurs in AWD electrical system, and control unit detects the malfunction, AWD warning
lamp on combination meter turns ON to indicate system malfunction
• AWD system activates its protection function (shuts down AWD system temporarily) if AWD system detects
high load continuously or the front wheel tire size differs from the rear tire size. (AWD system is automatically
restored if AWD system no longer detects any overload or the tire size difference is eliminated.)
Eeek, I recently got 275/35-20 front and 295/35-20 rear which is about 12.7mm difference assuming the diameters given by Michelin are exact, and that is on new tires... Since the fronts wear faster than the rears I may run into trouble...
 

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I guess time will tell. I'm also running 275/35 front and 295/35 rear. Give it six months, and we'll see that if the 0.5 inch will cause any problem.
 

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Discussion Starter · #10 ·
I guess time will tell. I'm also running 275/35 front and 295/35 rear. Give it six months, and we'll see that if the 0.5 inch will cause any problem.
Oh nice, have you tracked yours? That is my main concern...
 

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Sorry, can't answer your question because we don't even have a track here in HK.


But, I do think that the soft sidewalls may cause minor wobble in high-speed turn when you track your car.
 

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Discussion Starter · #12 ·
But, I do think that the soft sidewalls may cause minor wobble in high-speed turn when you track your car.
That shouldn't be a problem...
 

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On the older GT-R's having a height difference would/could cause the ATTESA system to turn off. I had an older car turn off the system with just bald rear tires, and nearly new front tires.

You might be able to play with pressures a bit to turn off but ultimately you really want to be as close to the same height as possible.

The difference in height can cause heat in the transfer case/fwd clutch. The differences in speed mean that there is slip, and slip becomes heat. As you are driving around and power is sent to the front, if you have a decent difference in sizes, you will have more slip, and more heat. On the older cars, I have destroyed a few transfer cases due to ignorance. On the R35, you don't even have the easy option of a transfer case, its the whole transmission.
 

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Discussion Starter · #14 ·
On the older GT-R's having a height difference would/could cause the ATTESA system to turn off. I had an older car turn off the system with just bald rear tires, and nearly new front tires.

You might be able to play with pressures a bit to turn off but ultimately you really want to be as close to the same height as possible.

The difference in height can cause heat in the transfer case/fwd clutch. The differences in speed mean that there is slip, and slip becomes heat. As you are driving around and power is sent to the front, if you have a decent difference in sizes, you will have more slip, and more heat. On the older cars, I have destroyed a few transfer cases due to ignorance. On the R35, you don't even have the easy option of a transfer case, its the whole transmission.
I guess I will find out since I am about to mount 275F and 295R very soon and track the car... I'm not sure I have much of a choice as I already bought and received them...
 
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