tire math ?
Thread Starter
Racer
Joined: Jul 2006
Posts: 354
Likes: 0
From: San bernardino ca
tire math ?
Sidewall Radius Diameter Circumference
3.7in 13.2in 26.4in 83.0in
4.0in 13.0in 26.0in 81.8in
my question is diameter total highet of wheel
and circumfrence is the same as if i took a piece of string and brought it around the outside that would be my circumference
and diameter is width of tire (footprint)
is this all correct
3.7in 13.2in 26.4in 83.0in
4.0in 13.0in 26.0in 81.8in
my question is diameter total highet of wheel
and circumfrence is the same as if i took a piece of string and brought it around the outside that would be my circumference
and diameter is width of tire (footprint)
is this all correct
Race Director
Joined: Mar 2005
Posts: 11,549
Likes: 27
From: Southampton NJ
Sidewall Radius Diameter Circumference
3.7in 13.2in 26.4in 83.0in
4.0in 13.0in 26.0in 81.8in
my question is diameter total highet of wheel
and circumfrence is the same as if i took a piece of string and brought it around the outside that would be my circumference
and diameter is width of tire (footprint)
is this all correct
3.7in 13.2in 26.4in 83.0in
4.0in 13.0in 26.0in 81.8in
my question is diameter total highet of wheel
and circumfrence is the same as if i took a piece of string and brought it around the outside that would be my circumference
and diameter is width of tire (footprint)
is this all correct
Last edited by dennis50nj; Feb 14, 2007 at 03:07 PM.
Drifting
Joined: Nov 2005
Posts: 1,745
Likes: 35
From: Turlock CA
Sidewall Radius Diameter Circumference
3.7in 13.2in 26.4in 83.0in
4.0in 13.0in 26.0in 81.8in
my question is diameter total highet of wheel
and circumfrence is the same as if i took a piece of string and brought it around the outside that would be my circumference
and diameter is width of tire (footprint)
is this all correct
3.7in 13.2in 26.4in 83.0in
4.0in 13.0in 26.0in 81.8in
my question is diameter total highet of wheel
and circumfrence is the same as if i took a piece of string and brought it around the outside that would be my circumference
and diameter is width of tire (footprint)
is this all correct
2) and circumfrence is the same as if i took a piece of string and brought it around the outside that would be my circumference -- yes, circumference or how far your tire travels in one rotation.
3) and diameter is width of tire (footprint) -- no, see #1.
Say you have a 245/35/18 tire --
245 is the width in millimeters (mm).
35 is the aspect ratio -- meaning what percent of the width is the sidewall height -- in this case 35%.
18 is the tire (and wheel) diameter.
To find the width of the tire in inches divide 245 by 25.4 (the number of mm to an inch) -- 245 / 25.4 = 9.65 inch.
The sidewall height is 9.65 inch times .35 (35%) -- 9.65 * 0.35 = 3.38 inch.
The diameter of the tire (and total height of your wheel) is 3.38 inch times 2 (you have to count top and bottom sides of the tire) plus the rim diameter -- 3.38 * 2 + 18 = 24.75 in.
Circumference is diameter times pi or in this case -- 24.75 * 3.1416 = 77.75 inches.
--Dan
Race Director
Joined: Mar 2005
Posts: 10,399
Likes: 25
From: Austin Texas
1) my question is diameter total highet of wheel -- total height - yes, in this case.
2) and circumfrence is the same as if i took a piece of string and brought it around the outside that would be my circumference -- yes, circumference or how far your tire travels in one rotation.
3) and diameter is width of tire (footprint) -- no, see #1.
Say you have a 245/35/18 tire --
245 is the width in millimeters (mm).
35 is the aspect ratio -- meaning what percent of the width is the sidewall height -- in this case 35%.
18 is the tire (and wheel) diameter.
To find the width of the tire in inches divide 245 by 25.4 (the number of mm to an inch) -- 245 / 25.4 = 9.65 inch.
The sidewall height is 9.65 inch times .35 (35%) -- 9.65 * 0.35 = 3.38 inch.
The diameter of the tire (and total height of your wheel) is 3.38 inch times 2 (you have to count top and bottom sides of the tire) plus the rim diameter -- 3.38 * 2 + 18 = 24.75 in.
Circumference is diameter times pi or in this case -- 24.75 * 3.1416 = 77.75 inches.
--Dan
2) and circumfrence is the same as if i took a piece of string and brought it around the outside that would be my circumference -- yes, circumference or how far your tire travels in one rotation.
3) and diameter is width of tire (footprint) -- no, see #1.
Say you have a 245/35/18 tire --
245 is the width in millimeters (mm).
35 is the aspect ratio -- meaning what percent of the width is the sidewall height -- in this case 35%.
18 is the tire (and wheel) diameter.
To find the width of the tire in inches divide 245 by 25.4 (the number of mm to an inch) -- 245 / 25.4 = 9.65 inch.
The sidewall height is 9.65 inch times .35 (35%) -- 9.65 * 0.35 = 3.38 inch.
The diameter of the tire (and total height of your wheel) is 3.38 inch times 2 (you have to count top and bottom sides of the tire) plus the rim diameter -- 3.38 * 2 + 18 = 24.75 in.
Circumference is diameter times pi or in this case -- 24.75 * 3.1416 = 77.75 inches.
--Dan
Thread Starter
Racer
Joined: Jul 2006
Posts: 354
Likes: 0
From: San bernardino ca
thank you to all the repys. in my situation i went with a 295 35 19 on a zo6 19x12 rim it does not work it looks like a$$. so if you read this and have a z06 or are doing a widebody wait and ill post pictures the rear tire crowns way to much. pulling proably at least 1/2 of total hiegth or more
Melting Slicks
Joined: Jun 2004
Posts: 3,439
Likes: 6
From: Newark, DE
St. Jude Donor '06
I think that's what dennis50nj (the first person to answer) was trying to tell you. The 1010 Tires calculator shows 11.5" as the widest wheel for a 295mm tire (and even that is a bit wide for a 295 IMO).
The calculator isn't perfect. For example, it shows the stock C6 Z06 size as "unknown." If it shows that a wheel is too wide or narrow for a given size, you can trust it though.
GL!
The calculator isn't perfect. For example, it shows the stock C6 Z06 size as "unknown." If it shows that a wheel is too wide or narrow for a given size, you can trust it though.
GL!
Drifting
Joined: Feb 2006
Posts: 1,250
Likes: 3
From: Honolulu HI
you could put a piece of tape on the ground mark it and the tire...
make one revolution put the second tape down and mark it.... (at the first mark from tire)
measure the distance of the two tape marks and divide that by 3.14 and it will give you a "loaded" diameter (what the car actually sees)....
the numbers will be different if say the tire was close to flat... (smaller diameter) or over-filled (larger diameter)...
as far as "footprint" goes - (part that touches the ground)... a tire will have a larger foot print if it flat...
and of course the opposite is true if over inflated.... (same size tire)
sorry.... very general - quick explanation.....
make one revolution put the second tape down and mark it.... (at the first mark from tire)
measure the distance of the two tape marks and divide that by 3.14 and it will give you a "loaded" diameter (what the car actually sees)....
the numbers will be different if say the tire was close to flat... (smaller diameter) or over-filled (larger diameter)...
as far as "footprint" goes - (part that touches the ground)... a tire will have a larger foot print if it flat...
and of course the opposite is true if over inflated.... (same size tire)
sorry.... very general - quick explanation.....
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