Square or Staggered? Track wheels & tires
#21
Mach 1 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: August 1, 2011
Location: Iowa
Posts: 802
Likes: 0
Received 0 Likes
on
0 Posts
History lesson
SCCA AutoX'rs lobbied Hoosier for that size so Hoosier took the 275 mold and shortened it a smidge and Hooray we now had a 255 that was as wide as a 275.
Who said anything about truth in advertising.
That is probably the biggest loop hole tire wise in NASA classing.
Peter
![Wink](https://themustangsource.com/forums/images/smilies/wink.gif)
![Worship](https://themustangsource.com/forums/images/smilies/worship.gif)
![Smile](https://themustangsource.com/forums/images/smilies/smile.gif)
Peter
Wow. Truth in advertising, what's that?
![Firedevil](https://themustangsource.com/forums/images/smilies/firedevil.gif)
#22
Cobra Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: August 5, 2008
Location: Arvada, CO
Posts: 1,369
Likes: 0
Received 0 Likes
on
0 Posts
This is the first I've heard of the 255/275 carcass sizing info -- would be very useful, and I might ultimately go that route.
According to the TireRack data, the 255/40-18 isn't the same width as the 255/35-18, so I'm assuming the 35 and 40 series tires are two entirely different molds? The two inch height reduction of the 35 series tires is pretty significant compared to the less than one inch change for the 40 series.
http://www.tirerack.com/tires/tires....r&tireModel=R6
According to the TireRack data, the 255/40-18 isn't the same width as the 255/35-18, so I'm assuming the 35 and 40 series tires are two entirely different molds? The two inch height reduction of the 35 series tires is pretty significant compared to the less than one inch change for the 40 series.
http://www.tirerack.com/tires/tires....r&tireModel=R6
#23
Member
Thread Starter
Join Date: August 20, 2011
Location: SF Bay Area, CA
Posts: 25
Likes: 0
Received 0 Likes
on
0 Posts
This is the first I've heard of the 255/275 carcass sizing info -- would be very useful, and I might ultimately go that route.
According to the TireRack data, the 255/40-18 isn't the same width as the 255/35-18, so I'm assuming the 35 and 40 series tires are two entirely different molds? The two inch height reduction of the 35 series tires is pretty significant compared to the less than one inch change for the 40 series.
http://www.tirerack.com/tires/tires....r&tireModel=R6
According to the TireRack data, the 255/40-18 isn't the same width as the 255/35-18, so I'm assuming the 35 and 40 series tires are two entirely different molds? The two inch height reduction of the 35 series tires is pretty significant compared to the less than one inch change for the 40 series.
http://www.tirerack.com/tires/tires....r&tireModel=R6
From Hoosier's site and the tire rack's site, there's another anomaly:
The 285/30-18 has a tread width of 10.9", while the 295/30 is 10.8" and the 295/40 is 10.5" (which is only .2" wider than the 10.3" 255/35-18)
I'm now considering going with R6's 255/35-18 for the front and 285/30-18 for the rear - this gets the tire diameters very close (24.8" front 24.9" rear).
#24
Shelby GT350 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: November 20, 2010
Location: Sioux Falls, SD
Posts: 2,384
Likes: 0
Received 1 Like
on
1 Post
Just going by specs - yes these tires are quite different.
From Hoosier's site and the tire rack's site, there's another anomaly:
The 285/30-18 has a tread width of 10.9", while the 295/30 is 10.8" and the 295/40 is 10.5" (which is only .2" wider than the 10.3" 255/35-18)
I'm now considering going with R6's 255/35-18 for the front and 285/30-18 for the rear - this gets the tire diameters very close (24.8" front 24.9" rear).
From Hoosier's site and the tire rack's site, there's another anomaly:
The 285/30-18 has a tread width of 10.9", while the 295/30 is 10.8" and the 295/40 is 10.5" (which is only .2" wider than the 10.3" 255/35-18)
I'm now considering going with R6's 255/35-18 for the front and 285/30-18 for the rear - this gets the tire diameters very close (24.8" front 24.9" rear).
#25
GT Member
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: August 26, 2011
Location: Hot Spot
Posts: 127
Likes: 0
Received 0 Likes
on
0 Posts
Peter
#27
Shelby GT350 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: November 20, 2010
Location: Sioux Falls, SD
Posts: 2,384
Likes: 0
Received 1 Like
on
1 Post
Who knows what all needs to be upgraded to achieve an acceptable failure rate for a production vehicle at speeds over 165. For example, a Super Snake was trying to hit 200 at the Texas Mile and despite numerous upgrades, a part that failed at 194 mph was the A/C compressor. They did a pulley delete and then the trans failed.
![Dunno](https://themustangsource.com/forums/images/smilies/dunno.gif)
#28
GT Member
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: August 26, 2011
Location: Hot Spot
Posts: 127
Likes: 0
Received 0 Likes
on
0 Posts
I'm going to say it doesn't remove it. I think the speed limiter is set to the lowest common denominator for parts engineered to a certain speed. I was told specifically that is the driveshaft, but haven't been able to confirm that directly from Ford. There are numerous parts that have to be engineered to withstand the rigors of high speed driving and the limiter is set accordingly.
Who knows what all needs to be upgraded to achieve an acceptable failure rate for a production vehicle at speeds over 165. For example, a Super Snake was trying to hit 200 at the Texas Mile and despite numerous upgrades, a part that failed at 194 mph was the A/C compressor. They did a pulley delete and then the trans failed.![Dunno](https://themustangsource.com/forums/images/smilies/dunno.gif)
Who knows what all needs to be upgraded to achieve an acceptable failure rate for a production vehicle at speeds over 165. For example, a Super Snake was trying to hit 200 at the Texas Mile and despite numerous upgrades, a part that failed at 194 mph was the A/C compressor. They did a pulley delete and then the trans failed.
![Dunno](https://themustangsource.com/forums/images/smilies/dunno.gif)
Peter
#29
Shelby GT350 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: November 20, 2010
Location: Sioux Falls, SD
Posts: 2,384
Likes: 0
Received 1 Like
on
1 Post
So did I, but myself and others have run it past there.....at least on the stock speedo (which reads high). True test is to get somewhere where I can do it with the GPS, but I haven't had an opportunity. I have hit 150 at BIR but run out of track. Airport or Texas Mile anyone???
Last edited by cloud9; 11/1/11 at 08:54 AM.
#30
Tasca Super Boss 429 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: December 18, 2010
Location: NorCal
Posts: 3,708
Likes: 0
Received 0 Likes
on
0 Posts
So did I, but myself and others have run it past there.....at least on the stock speedo (which reads high). True test is to get somewhere where I can do it with the GPS, but I haven't had an opportunity. I have hit 150 at BIR but run out of track. Airport or Texas Mile anyone???
![Wink](https://themustangsource.com/forums/images/smilies/wink.gif)
#31
Shelby GT350 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: November 20, 2010
Location: Sioux Falls, SD
Posts: 2,384
Likes: 0
Received 1 Like
on
1 Post
![Fear](https://themustangsource.com/forums/images/smilies/fear.gif)
#32
Square because you can rotate them--tires are my #1 expense for any track season.
I felt that an adjustable rear bar was needed for a square setup.
I felt that an adjustable rear bar was needed for a square setup.
#33
GT Member
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: August 26, 2011
Location: Hot Spot
Posts: 127
Likes: 0
Received 0 Likes
on
0 Posts
![Fear](https://themustangsource.com/forums/images/smilies/fear.gif)
![Wink](https://themustangsource.com/forums/images/smilies/wink.gif)
Peter
#35
Shelby GT350 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: November 20, 2010
Location: Sioux Falls, SD
Posts: 2,384
Likes: 0
Received 1 Like
on
1 Post
![Ohsnap](https://themustangsource.com/forums/images/smilies/ohsnap.gif)
#36
Shelby GT350 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: November 20, 2010
Location: Sioux Falls, SD
Posts: 2,384
Likes: 0
Received 1 Like
on
1 Post
Here's a good turn by turn description. I particularly like their description of Turn 9 under the bridge ![Rollinglaugh](https://themustangsource.com/forums/images/smilies/rollinglaugh.gif)
http://www.brainerdraceway.com/track...scription.html
![Rollinglaugh](https://themustangsource.com/forums/images/smilies/rollinglaugh.gif)
http://www.brainerdraceway.com/track...scription.html
#37
Shelby GT350 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: November 20, 2010
Location: Sioux Falls, SD
Posts: 2,384
Likes: 0
Received 1 Like
on
1 Post
![Doh](https://themustangsource.com/forums/images/smilies/doh.gif)
#38
GT Member
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: August 26, 2011
Location: Hot Spot
Posts: 127
Likes: 0
Received 0 Likes
on
0 Posts
It does. I'm just not smart enough to back off. I usually pick up quite a gap there between me and the car behind me. The trick is getting the car to "set" before turning in. There are a couple of slight bumps and when it "sets" on the second bump I turn in and go. I put my right tires just below the seam where they poured the new surface at the bottom of the turn. You should hit 150 before lifting, bleed off to around 120-130 and if you're flat footing it from the apex, hit 140 on exit. Turn 2 is the bigger pucker factor though since there's no banking and the surface is pretty rough. Brake a little harder than the other cars and turn in at about 110. You can be flat footed on the throttle at apex and exit at 130 which is faster than just trail braking in at 120. Oh and by the way, don't look at the trees because there isn't enough runoff to bleed off 130 mph in a 3600 lb car. ![Ohsnap](https://themustangsource.com/forums/images/smilies/ohsnap.gif)
![Ohsnap](https://themustangsource.com/forums/images/smilies/ohsnap.gif)
Peter
#39
#40
Shelby GT350 Member
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
![](https://themustangsource.com/forums/images/rank.gif)
Join Date: November 20, 2010
Location: Sioux Falls, SD
Posts: 2,384
Likes: 0
Received 1 Like
on
1 Post
Unless it was on GPS I would say it's suspect. My speedometer reads over 160 when my true speed is 150. Mfrs set the speedos high from the factory and it might be 2-3 mph at 70 but significantly further off at 150.