Tires Overheating? Help
Le Mans Master
Joined: Feb 2002
Posts: 6,937
Likes: 21
From: Waldorf MD
There is no "NO": from Tire Rack:
The European Tyre and Rim Technical Organization (ETRTO) establishes the standards for tires sold in Europe, and recognizes that the tire's deflection must be minimized and controlled in order to surpass high speed driving stresses. In order to accomplish this, the tire inflation pressure recommendations and the tire's rated load capacities are customized when speeds exceed 160 km/h (99 mph) for all tires up to and including a V-speed rating, and when speeds exceed 190 km/h (118 mph) for all tires that are Z-speed rated and above.
The Autobahn's unlimited speed opportunities explain why many German vehicles identify alternate tire inflation pressures to accommodate higher than North American highway speeds and heavier than typical two-passenger loads. In order to accommodate higher speeds, the tire size and inflation pressure recommendations are tuned beyond what is branded on the tire's sidewalls. These increases in recommended tire pressure are usually determined by agreement between the vehicle and tire manufacturers. In the absence of such an agreement, apply the following:
Beginning with the vehicle manufacturer's recommended tire pressure for normal highway conditions, tire inflation pressures are initially increased and then the tire's rated load capacities (branded on the sidewalls) are reduced as speeds climb.
In our example shown below, the vehicle manufacturer's recommended 35 psi for a 225/45R17 91W Standard Load tire installed on a vehicle initially rises in 1.5 psi increments for every 10 km/h (6.2 mph) increase in speed until the inflation pressures max out with an increase of 7.5 psi when the vehicle's top speed has increased 50 km/h (31mph). Then as the vehicle's top speed continues to climb, the rated load capacity of the tire is reduced in 5% increments for every additional 10 km/h until the vehicle's top speed has increased an additional 30 km/h (18.6 mph). In this case the 225/45R17 91W Standard Load size's rated load capacity of 1,477 lbs. is reduced to 1,255 lbs. when applied to a vehicle with a 270 km/h (168 mph) top speed.
For W-Speed Rated Tires
Vehicle
Top Speed Required Tire
Pressure Increase Tire Load Capacity
% of Branded Maximum W-Speed Rated Tire
35 psi O.E. Example
mph km/h psi bar % of value branded on sidewall psi lbs.
118 190 0 0 100% 35.0 1000
124 200 1.5 0.1 100% 36.5 1000
130 210 3.0 0.2 100% 38.0 1000
136 220 4.5 0.3 100% 39.5 1000
143 230 6.0 0.4 100% 41.0 1000
149 240 7.5 0.5 100% 42.5 1000
155 250 7.5 0.5 95% 42.5 950
161 260 7.5 0.5 90% 42.5 900
168 270 7.5 0.5 85% 42.5 850
NOTES: Never exceed the maximum cold inflation pressure branded on the tire's sidewall.
If a vehicle's horsepower and top speed are increased significantly, confirm that the required adjustments are made to the tire pressure and/or load conditions beyond the vehicle manufacturer's recommendations using the following charts.
R-Speed Rated Tires U-Speed Rated Tires V-Speed Rated Tires
S-Speed Rated Tires H-Speed Rated Tires W-Speed Rated Tires
T-Speed Rated Tires Z-Speed Rated Tires Y-Speed Rated Tires
More Tire Tech Information
Related Links:
Air Pressure - Correct, Underinflated and Overinflated
Air Pressure vs. Dry Performance
Air Pressure vs. Wet Performance
Air Pressure, Temperature Fluctuations
Air Pressure, Time Fluctuations
Air Pressure: When and How to Set
The European Tyre and Rim Technical Organization (ETRTO) establishes the standards for tires sold in Europe, and recognizes that the tire's deflection must be minimized and controlled in order to surpass high speed driving stresses. In order to accomplish this, the tire inflation pressure recommendations and the tire's rated load capacities are customized when speeds exceed 160 km/h (99 mph) for all tires up to and including a V-speed rating, and when speeds exceed 190 km/h (118 mph) for all tires that are Z-speed rated and above.
The Autobahn's unlimited speed opportunities explain why many German vehicles identify alternate tire inflation pressures to accommodate higher than North American highway speeds and heavier than typical two-passenger loads. In order to accommodate higher speeds, the tire size and inflation pressure recommendations are tuned beyond what is branded on the tire's sidewalls. These increases in recommended tire pressure are usually determined by agreement between the vehicle and tire manufacturers. In the absence of such an agreement, apply the following:
Beginning with the vehicle manufacturer's recommended tire pressure for normal highway conditions, tire inflation pressures are initially increased and then the tire's rated load capacities (branded on the sidewalls) are reduced as speeds climb.
In our example shown below, the vehicle manufacturer's recommended 35 psi for a 225/45R17 91W Standard Load tire installed on a vehicle initially rises in 1.5 psi increments for every 10 km/h (6.2 mph) increase in speed until the inflation pressures max out with an increase of 7.5 psi when the vehicle's top speed has increased 50 km/h (31mph). Then as the vehicle's top speed continues to climb, the rated load capacity of the tire is reduced in 5% increments for every additional 10 km/h until the vehicle's top speed has increased an additional 30 km/h (18.6 mph). In this case the 225/45R17 91W Standard Load size's rated load capacity of 1,477 lbs. is reduced to 1,255 lbs. when applied to a vehicle with a 270 km/h (168 mph) top speed.
For W-Speed Rated Tires
Vehicle
Top Speed Required Tire
Pressure Increase Tire Load Capacity
% of Branded Maximum W-Speed Rated Tire
35 psi O.E. Example
mph km/h psi bar % of value branded on sidewall psi lbs.
118 190 0 0 100% 35.0 1000
124 200 1.5 0.1 100% 36.5 1000
130 210 3.0 0.2 100% 38.0 1000
136 220 4.5 0.3 100% 39.5 1000
143 230 6.0 0.4 100% 41.0 1000
149 240 7.5 0.5 100% 42.5 1000
155 250 7.5 0.5 95% 42.5 950
161 260 7.5 0.5 90% 42.5 900
168 270 7.5 0.5 85% 42.5 850
NOTES: Never exceed the maximum cold inflation pressure branded on the tire's sidewall.
If a vehicle's horsepower and top speed are increased significantly, confirm that the required adjustments are made to the tire pressure and/or load conditions beyond the vehicle manufacturer's recommendations using the following charts.
R-Speed Rated Tires U-Speed Rated Tires V-Speed Rated Tires
S-Speed Rated Tires H-Speed Rated Tires W-Speed Rated Tires
T-Speed Rated Tires Z-Speed Rated Tires Y-Speed Rated Tires
More Tire Tech Information
Related Links:
Air Pressure - Correct, Underinflated and Overinflated
Air Pressure vs. Dry Performance
Air Pressure vs. Wet Performance
Air Pressure, Temperature Fluctuations
Air Pressure, Time Fluctuations
Air Pressure: When and How to Set
Last edited by Oldvetter; May 9, 2010 at 08:44 AM.
Melting Slicks
Joined: Apr 2003
Posts: 2,150
Likes: 6
From: NS
Not to mention that high tire pressure significantly increases the tire's spring rate potentially causing handling issues (reduced grip). The vehicle's suspension is tuned with the tire spring rate in mind and vice-versa. Running a DOT passenger tire at 40 - 50 psi is just wrong.
Melting Slicks
Joined: Sep 2005
Posts: 2,568
Likes: 264
From: Near Charlotte NC
Yes. You have too much air in the tires. Set the tire pressure to 32 psi front and 30 psi rear COLD.
and YES performance tires will spit out rubber. That is normal for a soft, performance tire that has grip.
you should see race tires, how much rubber or track turds get spitt out, stuck on the car, under the car, in the wheel wells and on rims.
get use to it
and YES performance tires will spit out rubber. That is normal for a soft, performance tire that has grip.
you should see race tires, how much rubber or track turds get spitt out, stuck on the car, under the car, in the wheel wells and on rims.
get use to it
I like to run UTOG 200-260 on all my rod cars.Grip is obtained by the shearing off of rubber,so that sounds like what you are doing....but do check the align just-in-case it seems excessive.
As always,IMO.
\db2
Carolina
