THE Tire Thread

[2112]

^^^^^How old?

 

[MAD IN NC]

Here is a link to Alex's "Store" on ebay:

<a href="http://stores.ebay.com/TA-Shocks?_trksid=p4340.l2563" target="_blank">http://stores.ebay.com/TA-Shocks?_trksid=p4340.l2563</a>

and you do need an alignment....... back to stock, light track or heavy track settings.

Here is the table from nota4re.

http://www.cooltechllc.com/GTForum/AlignmentPic.jpg

 

[MAD IN NC]

Check with Tire Buyer - they are a network of local shops where when I order I have to use their installers and locations as those site sell the tires. And you are obligated to have them mounted at their site, w state sales tax...

Problem was there is no conformation of date codes and worse yet no guarantee that they have a "road force" balancer..... I don't believe my local Shell can do a good job of mounting and balancing the rear's....


Tire Rack here I come.... pay for shipping, no tax and I get the balancing/ mounting where I know i trust the shop........

 

[tpraceman]

Hey call out to Shelby.
I went to tire rack and they listed several choices of the same tire make and model but different load ratings and prices.

I was hoping you could point me in the right direction.
I just want close to stock for street tires

Bridgestone RE050A Pole Position
265/40R18

Bridgestone RE050A Scuderia
345/35ZR19

Is this still the prefered choice for Stock BBS wheel street cars?
Chime in anyone as I don't want to change the wheels.

 

[KJRGT]

TPraceman, those are the specs I use and they are terrific.
I believe some fellas use a 255 instead of the 265 up front as well.

 

[fjpikul]

Raceman, you do not want the Pole Position. You want the Porsche N1 version in either 255 or 265 size.

 

[tpraceman]

Thanks Guys, I did the size search and in the same tire it came up with several of the exact part numbers but with different load ratings and prices.
Frank I am glad you said that & saved me a big mistake.
Tom

 

[otis]

Back to tires again... I am contemplating being a guinea pig for the new Michelin Pilot Super Sports. Have not seen anyone post about them so far. Was looking at the Pilot Sport Cup tires, but was concerned about how long they take to get up to temperature and how quickly they would wear in the back. My experience on the track is that they are a little loose and scary for the first lap, but once they get heated up are fantastic tires. They do wear fast and I could only get about 2 weekend track sessions on a set with my 911TT. My concern with the FGT is cold tires not warm tires. In Minnesota too many cold mornings the car and the road will be in the dangerous zone and I don't care to have one of those unexpected 2nd gear episodes. That is steering me away from R compounds or the Cup tires for daily use.

I have been a big fan of PS2s on my R8 and 911TT for daily driving, but both are AWD and have traction control. I also like the fact that everyone has posted very positive results of the PSSs over the PS2s except the weight is a touch higher. They are grippy when cold, wear well, predictable, and are quiet. I also like the fact that despite being 18% smaller the rears are 3" wider for better traction. Also the smaller tires effectively lower the drive ratio to improve acceleration.

My biggest concern is they are so small they don't fill out the wheel wells. I have T&A single adjustable coil-overs so I can drop the car to balance the front to rear and eliminate the wheels looking too small in the well. They will be going on the stock BBS wheels. Anyone have good close up shots of Michelins on the BBS wheels to see the size well?

My back up is still the Bridgestone RE050A tires, but I'm pulled by the Michelins and the extra 3" per side on the rears for traction. Anyone have any strong opinions on the PSSs or PS2s on these cars? I'm swaying back and forth looking for some advice to pull me in one direction over the other.

Thanks for the help.

Otis

 

[2112]

My back up is still the Bridgestone RE050A tires, but I'm pulled by the Michelins and the extra 3" per side on the rears for traction.
Otis

The Bridgestones are 345mm wide, I thought the Pilot SS were 335mm Wide.

Stock is 315mm and 1" is 25.4mm so I am lost on the additional 3".

As I am sure you know, not all manufacturers 335s are the same width, Are you saying the Pilot SS is 3" wider than the Bridgestones? :confused

Asking for clarification.

 

[Specracer]

Ralphie had the sport cups at the Utah Rally. I hope that there is a Supersport made for OEM wheels someday.

 

[Mullet]

Ralphie had the sport cups at the Utah Rally. I hope that there is a Supersport made for OEM wheels someday.

I've been running Supersports on the front for awhile.

 

[Specracer]

Correct, but they dont make a rear, and I dont want to mix tires front and back. I have been running R6 front and back.

 

[otis]

The Bridgestones are 345mm wide, I thought the Pilot SS were 335mm Wide.

Stock is 315mm and 1" is 25.4mm so I am lost on the additional 3".

As I am sure you know, not all manufacturers 335s are the same width, Are you saying the Pilot SS is 3" wider than the Bridgestones? :confused

Asking for clarification.

Goodyear F1 Supercar-----------315/40-19----------Tread width 10.2"---------Diameter 28.9"
Bridgestone RE050A Scuderia---345/35-19----------Tread width 11.5"---------Diameter 28.6"
Michelin Pilot Super Sports------345/30-19----------Tread width 13"-----------Diameter 27.2"


Above is per tirerack's website. This shows the lower profile PSS has 2.8" more tread width than the stock Goodyears and 1.5" more than the Bridgestones. This is what has my interest. The tread width is much wider on the Michelins which I would translate into more traction. The issue with the Michelins is they are 1.7" shorter than the stock tires. My concern is they are too small and make the wheel well look empty even with a considerable drop. Anyone else with experience with the PS2s or Cup tires in this size? Do they look small or reasonable?

Otis

 

[2112]

Wow, I would not have expected to see 1.5" (38.1mm) difference between two different 345s.

Thanks for citing the source.

 

[otis]

Wow, I would not have expected to see 1.5" (38.1mm) difference between two different 345s.

Thanks for citing the source.

I believe the difference can be explained by two reasons. First, the aspect ratio of the tire. Second, the roundness of the tire at the edge. Some tires have a round transition and some have a square edge. A very rounded edge profile has less flat tread on the ground and more sidewall. Some of the tread is actually up around the sidewall which places less on the ground. These tires tend to be very predictable at the limit (performance tires). Square edged tires have a very sharp transition, but put more tread in contact with the ground. These tires tend to be less predictable at the limit and let go quickly, but have massive traction right up to the limit (race tires).

Also 345 refers to measurement from the rim, down over the sidewall, across the tread, back up the sidewall to the rim on the other side. If the profile ratio (30 vs 35 in this case) is lower the sidewall is shorter and the tread width is wider for the same 345mm measurement. Since the PSS has the lower profile 30 ratio more tread and less sidewall make up the measurement. I think this explains why the PSS is wider than the RE050As. For me more on the ground = less chance of a spin.

Otis

 

[2112]

Also 345 refers to measurement from the rim, down over the sidewall, across the tread, back up the sidewall to the rim on the other side.

I always thought it was from sidewall to sidewall, a straight line thru the tire. :facepalm:

For me more on the ground = less chance of a spin.

Otis

Agreed, unless it is icy. :frown

 

[Superfly]

I always thought it was from sidewall to sidewall, a straight line thru the tire. :facepalm:

It is. But the 'width' can vary a bit depending on the size of rim you put it on. I've never seen the description otis has said. Maybe it's the new math...... :wink

 

[otis]

Sorry I seem to have had a stupid moment?????

Otis


Section Width

Following the letter(s) that identify the type of vehicle and/or type of service for which the tire was designed, the three-digit numeric portion identifies the tire's "Section Width" (cross section) in millimeters.

P225/50R16 91S

The 225 indicates this tire is 225 millimeters across from the widest point of its outer sidewall to the widest point of its inner sidewall when mounted and measured on a specified width wheel. This measurement is also referred to as the tire's section width. Because many people think of measurements in inches, the 225mm can be converted to inches by dividing the section width in millimeters by 25.4 (the number of millimeters per inch).

225mm / 25.4 = 8.86"

Sidewall Aspect Ratio

Typically following the three digits identifying the tire's Section Width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.

P225/50R16 91S

The 50 indicates that this tire size's sidewall height (from rim to tread) is 50% of its section width. The measurement is the tire's section height, and also referred to as the tire's series, profile or aspect ratio. The higher the number, the taller the sidewall; the lower the number, the lower the sidewall. We know that this tire size's section width is 225mm and that its section height is 50% of 225mm. By converting the 225mm to inches (225 / 25.4 = 8.86") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of 4.43". If this tire were a P225/70R16 size, our calculation would confirm that the size would result in a section height of 6.20", approximately a 1.8-inch taller sidewall.

 

[otis]

repost

 

[otis]

Some tires have a round transition and some have a square edge. A very rounded edge profile has less flat tread on the ground and more sidewall. Some of the tread is actually up around the sidewall which places less on the ground. These tires tend to be very predictable at the limit (performance tires). Square edged tires have a very sharp transition, but put more tread in contact with the ground. These tires tend to be less predictable at the limit and let go quickly, but have massive traction right up to the limit (race tires).

Otis

Does this explain why the Michelins have a wider tread than the Bridgestones then? I'm confused??? The Bridgestones are more rounded and thus wider in the middle of the sidewall and narrower in the tread width. The Michelins are more squared and the sidewall width and the tread width are closer together?

Otis