2008 Porsche Boxster
tire size detail
(Winter Tires)
Front Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
205 millimeters
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.
The 205 indicates that this tire is 205 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 205mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
205mm / 25.4 = 8.07"
Aspect Ratio
55%
The ratio of the height of the tire's cross-section to it's width. 55 means that the height is equal to 55% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 55 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 205mm and that its section height is 50% of 205mm. By converting the 205mm to inches (205 / 25.4 = 8.07") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of4.04".
Construction Method
R ... Radial
The R in the 205/55R17 91V size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (205/55R17 91V), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
17" wheel
The 17 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (205/55R17 91V, as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Speed Rating
... mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (205/55R17 91V) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
Rear Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
235 millimeters
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.
The 235 indicates that this tire is 235 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 235mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
235mm / 25.4 = 9.25"
Aspect Ratio
50%
The ratio of the height of the tire's cross-section to it's width. 50 means that the height is equal to 50% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 50 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 235mm and that its section height is 50% of 235mm. By converting the 235mm to inches (235 / 25.4 = 9.25") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of4.63".
Construction Method
R ... Radial
The R in the 235/50R17 96VF: 205/55R17 91Y size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (235/50R17 96VF: 205/55R17 91Y), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
17" wheel
The 17 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (235/50R17 96VF: 205/55R17 91Y, as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Load Range/Ply Rating
55
This tire has a ply rating of which indicates how much load the tire is designed to carry at it's specified pressure.
Load Index/Service Description
R ... NaNlb load
The tire assigned numerical value used to compare relative load carrying capabilities.
The R represents the tire's service description. A service description identifies the tire's load index and speed rating. Service descriptions are required on all speed rated (except for Z-speed rated) tires manufactured since the early 1990s.
Speed Rating
17 ... mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (235/50R17 96VF: 205/55R17 91Y) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
Base
F: 205/55R17 91YR: 235/50R17 96Y
(click for a tire code explanation)
Front Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
205 millimeters
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.
The 205 indicates that this tire is 205 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 205mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
205mm / 25.4 = 8.07"
Aspect Ratio
55%
The ratio of the height of the tire's cross-section to it's width. 55 means that the height is equal to 55% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 55 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 205mm and that its section height is 50% of 205mm. By converting the 205mm to inches (205 / 25.4 = 8.07") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of4.04".
Construction Method
R ... Radial
The R in the 205/55R17 91Y size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (205/55R17 91Y), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
17" wheel
The 17 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (205/55R17 91Y, as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Speed Rating
... mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (205/55R17 91Y) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
Rear Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
235 millimeters
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.
The 235 indicates that this tire is 235 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 235mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
235mm / 25.4 = 9.25"
Aspect Ratio
50%
The ratio of the height of the tire's cross-section to it's width. 50 means that the height is equal to 50% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 50 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 235mm and that its section height is 50% of 235mm. By converting the 235mm to inches (235 / 25.4 = 9.25") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of4.63".
Construction Method
R ... Radial
The R in the 235/50R17 96Y size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (235/50R17 96Y), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
17" wheel
The 17 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (235/50R17 96Y, as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Speed Rating
... mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (235/50R17 96Y) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
S (Winter Tires)
Front Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
235 millimeters
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.
The 235 indicates that this tire is 235 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 235mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
235mm / 25.4 = 9.25"
Aspect Ratio
40%
The ratio of the height of the tire's cross-section to it's width. 40 means that the height is equal to 40% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 40 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 235mm and that its section height is 50% of 235mm. By converting the 235mm to inches (235 / 25.4 = 9.25") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of4.63".
Construction Method
R ... Radial
The R in the 235/40R18 91V size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (235/40R18 91V), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
18" wheel
The 18 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (235/40R18 91V, as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Speed Rating
... mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (235/40R18 91V) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
Rear Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
255 millimeters
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.
The 255 indicates that this tire is 255 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 255mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
255mm / 25.4 = 10.04"
Aspect Ratio
40%
The ratio of the height of the tire's cross-section to it's width. 40 means that the height is equal to 40% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 40 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 255mm and that its section height is 50% of 255mm. By converting the 255mm to inches (255 / 25.4 = 10.04") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of5.02".
Construction Method
R ... Radial
The R in the 255/40R18 95VF: 235/40ZR18 (91Y) size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (255/40R18 95VF: 235/40ZR18 (91Y)), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
18" wheel
The 18 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (255/40R18 95VF: 235/40ZR18 (91Y), as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Load Range/Ply Rating
40
This tire has a ply rating of which indicates how much load the tire is designed to carry at it's specified pressure.
Load Index/Service Description
ZR ... NaNlb load
The tire assigned numerical value used to compare relative load carrying capabilities.
The ZR represents the tire's service description. A service description identifies the tire's load index and speed rating. Service descriptions are required on all speed rated (except for Z-speed rated) tires manufactured since the early 1990s.
Speed Rating
18 ... mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (255/40R18 95VF: 235/40ZR18 (91Y)) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
(18 Inch Option), Limited Edition, S
F: 235/40ZR18 (91Y)R: 265/40ZR18/RF (101Y)
(click for a tire code explanation)
Front Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
235 millimeters
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.
The 235 indicates that this tire is 235 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 235mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
235mm / 25.4 = 9.25"
Aspect Ratio
40%
The ratio of the height of the tire's cross-section to it's width. 40 means that the height is equal to 40% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 40 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 235mm and that its section height is 50% of 235mm. By converting the 235mm to inches (235 / 25.4 = 9.25") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of4.63".
Construction Method
R ... Radial
The R in the 235/40ZR18 (91Y) size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (235/40ZR18 (91Y)), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
18" wheel
The 18 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (235/40ZR18 (91Y), as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Speed Rating
Z ... over 240mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (235/40ZR18 (91Y)) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
Rear Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
265 millimeters
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.
The 265 indicates that this tire is 265 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 265mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
265mm / 25.4 = 10.43"
Aspect Ratio
40%
The ratio of the height of the tire's cross-section to it's width. 40 means that the height is equal to 40% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 40 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 265mm and that its section height is 50% of 265mm. By converting the 265mm to inches (265 / 25.4 = 10.43") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of5.21".
Construction Method
R ... Radial
The R in the 265/40ZR18/RF (101Y) size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (265/40ZR18/RF (101Y)), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
18" wheel
The 18 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (265/40ZR18/RF (101Y), as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Load Range/Ply Rating
RF
This tire has a ply rating of which indicates how much load the tire is designed to carry at it's specified pressure.
Load Index/Service Description
( ... NaNlb load
The tire assigned numerical value used to compare relative load carrying capabilities.
The ( represents the tire's service description. A service description identifies the tire's load index and speed rating. Service descriptions are required on all speed rated (except for Z-speed rated) tires manufactured since the early 1990s.
Speed Rating
101 ... mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (265/40ZR18/RF (101Y)) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
S (19 Inch Option)
F: 235/35R19 (87Y)R: 265/35ZR19 (94Y)F: 235/35ZR19 (87Y)R: 265/35ZR19 (94Y)
(click for a tire code explanation)
Front Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
235 millimeters
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.
The 235 indicates that this tire is 235 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 235mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
235mm / 25.4 = 9.25"
Aspect Ratio
35%
The ratio of the height of the tire's cross-section to it's width. 35 means that the height is equal to 35% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 35 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 235mm and that its section height is 50% of 235mm. By converting the 235mm to inches (235 / 25.4 = 9.25") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of4.63".
Construction Method
R ... Radial
The R in the 235/35R19 (87Y) size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (235/35R19 (87Y)), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
19" wheel
The 19 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (235/35R19 (87Y), as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Speed Rating
... mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (235/35R19 (87Y)) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
Rear Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
265 millimeters
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.
The 265 indicates that this tire is 265 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 265mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
265mm / 25.4 = 10.43"
Aspect Ratio
35%
The ratio of the height of the tire's cross-section to it's width. 35 means that the height is equal to 35% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 35 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 265mm and that its section height is 50% of 265mm. By converting the 265mm to inches (265 / 25.4 = 10.43") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of5.21".
Construction Method
R ... Radial
The R in the 265/35ZR19 (94Y)F: 235/35ZR19 (87Y) size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (265/35ZR19 (94Y)F: 235/35ZR19 (87Y)), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
19" wheel
The 19 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (265/35ZR19 (94Y)F: 235/35ZR19 (87Y), as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Load Range/Ply Rating
35
This tire has a ply rating of which indicates how much load the tire is designed to carry at it's specified pressure.
Load Index/Service Description
ZR ... NaNlb load
The tire assigned numerical value used to compare relative load carrying capabilities.
The ZR represents the tire's service description. A service description identifies the tire's load index and speed rating. Service descriptions are required on all speed rated (except for Z-speed rated) tires manufactured since the early 1990s.
Speed Rating
19 ... mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (265/35ZR19 (94Y)F: 235/35ZR19 (87Y)) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
(19 Inch Option), RS 60 Spyder, S Limited Edition
F: 235/35ZR19 (87Y)R: 265/35ZR19 (94Y)
(click for a tire code explanation)
Front Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
235 millimeters
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.
The 235 indicates that this tire is 235 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 235mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
235mm / 25.4 = 9.25"
Aspect Ratio
35%
The ratio of the height of the tire's cross-section to it's width. 35 means that the height is equal to 35% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 35 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 235mm and that its section height is 50% of 235mm. By converting the 235mm to inches (235 / 25.4 = 9.25") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of4.63".
Construction Method
R ... Radial
The R in the 235/35ZR19 (87Y) size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (235/35ZR19 (87Y)), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
19" wheel
The 19 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (235/35ZR19 (87Y), as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Speed Rating
Z ... over 240mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (235/35ZR19 (87Y)) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
Rear Tires
Intended Use Of Tire
P ... Passenger Vehicle
When a tire size begins with a P, it signifies the tire is a p-metric size that was designed to be fitted on vehicles that are primarily used as passenger vehicles. This includes cars, minivans, sport utility vehicles and light duty pickup trucks (typically 1/4- and 1/2-ton load capacity). The use of p-metric sizes began in the late 1970s and they are the most frequently used type of tire size today.
Tire Width
265 millimeters
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.
The 265 indicates that this tire is 265 millimeters across from the widest point when mounted and measured on a specified width wheel. Because many people think of measurements in inches, the 265mm can be converted to inches by dividing the width in millimeters by 25.4 (the number of millimeters per inch).
265mm / 25.4 = 10.43"
Aspect Ratio
35%
The ratio of the height of the tire's cross-section to it's width. 35 means that the height is equal to 35% of the tire's width.
Typically, following the three digits identifying the tire's width in millimeters is a two-digit number that identifies the tire's profile or aspect ratio.
The 35 indicates that this tire size's sidewall height (from rim to tread) is 50% of its 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 265mm and that its section height is 50% of 265mm. By converting the 265mm to inches (265 / 25.4 = 10.43") and multiplying it by 50% (.50) we confirm that this tire size results in a tire section height of5.21".
Construction Method
R ... Radial
The R in the 265/35ZR19 (94Y) size identifies that the tire has a radial construction in which the tire's plies "radiate" out from the center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (265/35ZR19 (94Y)), it would identify that the internal tire body plies crisscross on a diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
Rim Size
19" wheel
The 19 indicates the tire and wheel diameter designed to be matched together.
Tires that have a rim diameter expressed in inches (265/35ZR19 (94Y), as well as8, 10, 12, 13,14,15, 17, 18, 19,20, 22, 23, 24,26 and 28) are called "inch rim" sizes. These are the most common types of tire sizes and are used on most cars, minivans, vans, sport utility vehicles and light duty light trucks.
Tires and wheels with unique rim diameters should never be combined with traditional "inch rim" tires and wheels.
Speed Rating
Z ... over 240mph
The maximum speed that the tire can sustain for 10 minutes.
Today, the only tires that continue to include the speed rating "in" the tire size (265/35ZR19 (94Y)) are Z-speed rated tires. In this case, following the two digits used to identify the aspect ratio are the letters ZR to identify the tire's speed rating (Z) and its internal construction (R). Since 1991, all other speed ratings are identified in the tire's Service Description.
Dr. Ing. h.c. F. Porsche AG, usually shortened to Porsche, is a German automobile manufacturer specializing in high-performance sports cars, SUVs and sedans. Porsche AG is headquartered in Stuttgart, and is owned by Volkswagen AG, which is itself majority-owned by Porsche Automobil Holding SE. Porsche's current lineup includes the 718 Boxster/Cayman, 911, Panamera, Macan and Cayenne.