ST6/TT6 Tire Section Width Guide

[1jeffcat]

I figured I would start a section width guide for the ST6/TT6 as a tool for current and future participants to develop their builds with information in hand, as opposed to having to guess on purchases prior to later find out that their wheel/tire combination doesn't fit their desired section width rules.

 

It's important to keep in mind that there are a variety of tires and wheels, which can subtly alter your section width results, while attempting to meet the section width template of your choosing. This is why wheel type and size are listed as not EVERY 15x8 wheel is EXACTLY 8" wide, nor do they all have the same lip design which may or may not make or break you meeting a section width template.

 

List your setup in this format if possible for accuracy:

Tire Brand/Model:

Tire Size:

Wheel Model/Size:

 

General Rules:

https://scontent-lga3-1.xx.fbcdn.net/v/t1.0-9/fr/cp0/e15/q65/46301016_10112898622973085_796986621210656768_o.jpg?_nc_cat=109&efg=eyJpIjoidCJ9&_nc_ht=scontent-lga3-1.xx&oh=b3b453fac3336f1f7b38ba97af4b36f2&oe=5C89216F

Section Width Templates:

https://nasa-assets.s3.amazonaws.com/document/document/12756/NASA_Tire_Tool_Template_-_2017_REV1_.pdf

 

Link to Izzy's, who sells pre-made section width templates:

https://www.izzyscustomcages.com/product-page/nasa-tire-section-tool-super-touring

 

 

 

Edited November 16, 2018 by 1jeffcat

[1jeffcat]

Preliminary information. 23mm references the 226mm template. 30mm references the 257mm template.

 

 

[1jeffcat]

Tire Brand/Model: Continental Tires Series Slick

Tire Size: 225/45/18

Wheel Model/Size:BBS RC 303 18x8.5

Clears 257mm template easily. Does not clear 226mm template.

 

[1jeffcat]

Tire Brand/Model: BFGoodrich Rival

Tire Size: 225/45/15

Wheel Model/Size: Enkei RPF1 15x8

Easily clears 226mm template

 

[1jeffcat]

Tire Brand/Model: Bridgestone RE71R

Tire Size: 225/45/17

Wheel Model/Size: Ray's Engineering ZE40 17x7.5

Easily clears 226mm template

 

[1jeffcat]

Tire Brand/Model: Toyo RR

Tire Size: 255/40/17

Wheel Model/Size: Enkei unknown wheel 17x9

clears 257mm template with a little room left

[1jeffcat]

Tire Brand/Model: Hankook RS4

Tire Size: 225/45/17

Wheel Model/Size: Apex Arc-8 17x8.5

clears 226mm template easily

[1jeffcat]

Tire Brand/Model: Bridgestone RE71R

Tire Size: 255/40/17

Wheel Model/Size: Unknown Wheel and Size...I'm guessing 17x9

clears 257mm template easily

[1jeffcat]

Tire Brand/Model: Nexen Nfera Sur4

Tire Size: 255/40/17

Wheel Model/Size: Enkei RPF1 17x9.5

Fits 257mm template EXACTLY. This is so close that you REALLY have to account for mounting and manufacturing defects as you couldn't possibly have a more perfect fitment. The guage fits snugly, but does fall off easily. There is no space between gauge and tire.

[1jeffcat]

Tire Brand/Model: Bridgestone RE71R

Tire Size: 255/40/17

Wheel Model/Size: Enkei RPF1 17x9.5

clears 257mm template with some extra room

[1jeffcat]

Tire Brand/Model: BFGoodrich Rival S

Tire Size: 225/45/15

Wheel Model/Size: 949 6UL 15x9

clears 226mm with some extra room

Edited September 7, 2018 by Guest

[1jeffcat]

Tire Brand/Model: Maxxis RC1

Tire Size: 245/40/15

Wheel Model/Size: 949 6UL 15x10

clears 257mm with a little extra room

[1jeffcat]

Tire Brand/Model: Hoosier R7

Tire Size: 245/40/15

Wheel Model/Size: Unknown wheel model 15x8

clears 257mm with a little extra room

[dadasracecar]

225/45-15 Hoosier R7

Unknown SM wheel 15x7”

Fits 226 perfectly.

[efposs]

Im having a problem with Hoosier 205 - 50/15 r7 making 226 on 8 inch wheels, cranking tire pressure to 32-35 it gets there. Why couldnt we just have 228. Ill probably start at 2400 lbs at the beginning of the year and let everyone else get dqed.

[cabowabo]

On 9/12/2018 at 6:24 PM, dadasracecar said:

225/45-15 Hoosier R7

Unknown SM wheel 15x7”

Fits 226 perfectly.

...but is it any faster than 205 on 8? Because what's effectively a 245 on 7" wide wheel sounds atrocious, but if it's faster it's faster. 

[frozen honda]

Has anyone measured a 205 50 15 RE71R on a 15x7.5" wheel? TRMotorsports C1 wheel ideally. Thanks.

[frozen honda]

I contacted Tire Rack to see if they are interested in mocking up tire and wheel combinations for measurement as a service to their customers in the racing community. I would rather pay a small fee to find out legality of a particular tire / wheel combination before I buy a season's worth of tires. Maybe if a few others make this same suggestion TR would consider it. Their brand identity is partly based on being supportive of motorsports and this would fit right in.

[H4CRXSi]

On 9/6/2018 at 8:59 PM, 1jeffcat said:

Tire Brand/Model: Hoosier R7

Tire Size: 245/40/15

Wheel Model/Size: Unknown wheel model 15x8

clears 257mm with a little extra room

Given that a 245/40/15 Hoosier R7 on a 15x8 rim clears the 257mm template, is it safe to think that a 225/45/15 Hoosier R7 on a 15x9 rim will clear the same 257mm template?

[Mike W.]

On 2/27/2019 at 3:12 PM, H4CRXSi said:

Given that a 245/40/15 Hoosier R7 on a 15x8 rim clears the 257mm template, is it safe to think that a 225/45/15 Hoosier R7 on a 15x9 rim will clear the same 257mm template?

Pretty sure they do.  I think that is what Neuman was planning to run at Nationals last year.

[frozen honda]

The 205/50R15 Bridgestone Potenza RE71R on 15x7.5 wheel easily clears the NASA 226 @ 23mm gauge. Someone was kind enough to measure this for me.

[1jeffcat]

On 3/5/2019 at 7:24 PM, frozen honda said:

The 205/50R15 Bridgestone Potenza RE71R on 15x7.5 wheel easily clears the NASA 226 @ 23mm gauge. Someone was kind enough to measure this for me.

Yes, that easily clears.  Most 225 200tw tires on 9" wheels clear the 226.

[1jeffcat]

On 2/27/2019 at 4:12 PM, H4CRXSi said:

Given that a 245/40/15 Hoosier R7 on a 15x8 rim clears the 257mm template, is it safe to think that a 225/45/15 Hoosier R7 on a 15x9 rim will clear the same 257mm template?

Yes, should easily clear.  225 hoosiers don't have the huge size difference that 205 hoosiers have.  205 hoosiers almost fit the 226 on 15x9s, but don't.  It is so close, that I think a 15x8.5 and hoosier 205 MIGHT clear the 226, but I can't validate it as I don't have a 15x8.5.  With that said 225 Hoosiers easily clear the 257 on 9s.  As a point of reference, 245 Maxxis have a larger section width than 225 hoosiers....9.8" vs 9.3", and 245 Maxxis on 15x10s clear the 257.

[AZELISE]

Hoosier A7

205/50-15

SSR Comp 15x7.5

Clears the 226 mm with about 6 mm to spare. Yes I am aware the A7 is not allowed in ST/TT 5 and 6.

Toyo RR

225/45-15

SSR Comp 15x7

Clears the 226 mm with about 12 mm to spare. 

Edited March 27, 2019 by AZELISE

[AZELISE]

On 3/17/2019 at 3:18 PM, 1jeffcat said:

Yes, should easily clear.  225 hoosiers don't have the huge size difference that 205 hoosiers have.  205 hoosiers almost fit the 226 on 15x9s, but don't.  It is so close, that I think a 15x8.5 and hoosier 205 MIGHT clear the 226, but I can't validate it as I don't have a 15x8.5.  With that said 225 Hoosiers easily clear the 257 on 9s.  As a point of reference, 245 Maxxis have a larger section width than 225 hoosiers....9.8" vs 9.3", and 245 Maxxis on 15x10s clear the 257.

efposs posted on Nov 27, 2018 that they were having a problem with a Hoosier 205/50-15 working with an 8” wheel.