Tread width

[benzopyrene]

So trying to understand this a little bit better. I am looking to pick up some michelin Pilot SS for my nw forgestar CF10s. I had settled a couple months ago on going 275/35/r20 in the front and 315/35r20 in the back. However, looking at more specs it looks to me as though the 295/35r20's are actually just as wide (tread width as the 315's. Can somebody shed some light on this for me. I am curious because it is a little bit closer diameter wise to the 275's, so I am leaning towards the 275's. But there are actually a few different versions of each of these tires...and thats a littlle confusing as well. At any rate if anybody could shed some light on this for me I'd appreciate it. Which tire will actually put more rubber on the pavement?

 

[Jabooh1]

What width are your rims? If you have a wide tire on a narrow rim you will actually decrease the contact patch.

 

[dirtyd88]

There is section width, and there is tread width, which can be attributed to contact patch.

The 275, 295 and 315 you see on the tires is the section width, which is the measurement of the widest part of the tire, typically outside of the sidewall apex to outside of the other sidewall apex. the tread width essentially the width of the actual tread itself that should contact the road (contact patch), depending on how wide your wheel is. People always misunderstand that just because you put a big ass tire on a wheel and it fits, doesn't mean you are getting the largest contact patch as possible. So you have decreased traction relative to a smaller tire on the same wheel because the tread is starting to roll up the sidewall since the tire is "buldging".

This is my best explanation anyways.

TireRack links

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=10
http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=7

 

[benzopyrene]

sorry guys didnt mean to leave that out. 20x9 up front and 20x11 out back on the rim size

 

[benzopyrene]

its just interesting to me that with the 295/35r20 K1 xl MPss I can get 12in of tread width with a 28.1 in diam, but with the 315/35r20 xl K1 MPSS I only get 11.5in tread width with 28.8 in diameter. Also not really sure how I can get 12 in tread width on the 295 if the sectional diameter is on 11.9... anybody able to explain this? These specs all come from tirerack fyi. Thanks for all the useful info guys.

 

[Scott8583]

Has to be a typo...

 

[Jabooh1]

I have called TireRack before and the Techs are very useful. Might look up on the Mich. website as well.

 

['14 Shelby]

its just interesting to me that with the 295/35r20 K1 xl MPss I can get 12in of tread width with a 28.1 in diam, but with the 315/35r20 xl K1 MPSS I only get 11.5in tread width with 28.8 in diameter. Also not really sure how I can get 12 in tread width on the 295 if the sectional diameter is on 11.9... anybody able to explain this? These specs all come from tirerack fyi. Thanks for all the useful info guys.

If I understand what you wrote I think youre reading the sizing incorrectly regarding diameter. 295 is width in mm & 35 = 35% of 295mm. so the 315 would naturally be a larger diameter as it is also 35% but of a larger width.

OR

as the other reply said it must be a typo

295mm = 11.6 inch
315mm = 12.4 inch

 

[dirtyd88]

Pulled from Michelin's website

295/35/20 XL, 10.0" - 11.5", 11.9" on 10.5", 28.1", 740, 9/32", 2039@50, 30.9#, PN 09045
315/35/20 XL, 10.5" - 12.5", 12.6" on 11.0", 28.6", 726, 10/32" , 2336@50, 33.3#, PN 79340

 

[Zandura99]

1 935YR0PSS 295/35R20~ MI PILT SUPER SPRT 390.00
(101Y) K1 (Ferrari) 9/32nds 11.9 section width on 10.5 wheel. Tread: 11.6

1 935YR0PSSXL 295/35R20~ MI PILT SUPER SPRT 423.00
(105Y) K1 (Ferrari) 9/32nds 11.9 section width on 10.5 wheel. Tread: 12.0

1 135YR0PSSXL 315/35R20~ MI PILT SUPER SPRT 393.00
(110Y) K1 (Ferrari) 7/32nds 12.6 section width on 11.0 wheel. Tread: 11.5

1 135YR0PSSXLV2 315/35R20~ MI PILT SUPER SPRT* 434.00
(110Y) K2 (Ferrari) 10/32nds 12.6 section width 11.0 wheel. Tread: 13.0

This is the info on our site (Tire Rack). I work here AND love mustangs so I am on the site often.
I have asked my support team to clarify the tread width.

stay tuned.

 

[Zandura99]

here are final measured tread widths:

1 935YR0PSS 295/35R20~ MI PILT SUPER SPRT 390.00
(101Y) K1 (Ferrari) 9/32nds 11.9 section width on 10.5 wheel. Tread: 11.6

1 935YR0PSSXL 295/35R20~ MI PILT SUPER SPRT 423.00
(105Y) K1 (Ferrari) 9/32nds 11.9 section width on 10.5 wheel. Tread: 11.3 (was 12.0)

1 135YR0PSSXL 315/35R20~ MI PILT SUPER SPRT 393.00
(110Y) K1 (Ferrari) 7/32nds 12.6 section width on 11.0 wheel. Tread: 11.5

1 135YR0PSSXLV2 315/35R20~ MI PILT SUPER SPRT* 434.00
(110Y) K2 (Ferrari) 10/32nds 12.6 section width 11.0 wheel. Tread: 12.0 (was 13.0)

Because they have varying OE applications, they are slightly different. Also, every 1/2 inch of wheel width different from the measured wheel width (above after section width) will change the section width by .2 inch accordingly. So, the 423 dollar MI PSS on an 11 inch wheel will have an 12.1 section width. I would assume less impact of the tread that the section width due to rim though.

 

[benzopyrene]

awesome! Very very helpful! Thank you so much!