Handling/comfort/treadlife
Handling/comfort/treadlife
what would u'll say is the most important....looking for a good pair of tires for my Q.......nd just want to get some other opnions on what you guys like.....might be it is what i like too =-D
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Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Speed rating are essentially the speed at which a brand new [less than 1,000 miles] tire will not explode when loaded to a load appropriate for the inflation pressure when going straight against a simulated road [big metal drum] in a laboratory when the tread temperature does not exceed 100F. [When it is 90F outside and you drive at 70 mph - THE TIRE TREAD TEMPERATURE WILL BE OVER 150F after 15 minutes BECAUSE the lab test don't consider camber or toe as a parameter!
Not useful for the real world unless you are a manufacturer trying to test quality control.
The problem with speed rating is you have no way of downwardly adjusting the effects of tire age and stress, oxygen exposure, road temperature, or actual load vs inflation.
Buying a 108 mph is foolish because even though you don't drive 108 mph........the tire when aged may be in reality a 85-90 mph tire in Summer heat after 4 hours with less than 10,000 miles on it.
Why do speed rated tires fail at speeds lower than rating? The car load exceeds the test proceedure or they were made cheaply, good enough to pass the test brand new but not used/worn.
Even though the oem Michelins were V rated they were the best V rated money could buy..............probably exceed the V rating test by 20% because Infiniti felt safe enough to ferry reporters around the Arizona test track at 159 mph 3 to the car with professsional drivers at the wheel [back in 1989 during lauch press introduction].......That was 10 mph greater than the tires were rated for!
If you never exceed the speed limit [75 mph] the minimum speed rating would be should be H rated.........130 mph new maybe 100 mph whenever worn to the bars. That way IF the inflation is too low [even 20 psi if it is well made], the tire won't fail at 75-80 mph in summer heat after 4 hours.
not guaranteed but high probability.
The other factor is load rating [how much weight the tire can support at maximum inflation before exploding] in a similar straight ahead non rigours test..............with a tire less than oem rating all bets are off and WITH a lower than factory speed rating is a double whammy.
OEM tires are designed to wear fast because they know that the tires WON'T meet specs as they age unless they are over built to begin with and very few tires are over built due to competitive pricing pressures. Michelin is the only company that has chosen to over build and you pay for it.
I feel safe with a Michelin H rated as long as the load index is higher than oem. When I must buy a V rated I make sure the load rating is equal to oem.
All about safety margin and strength to survive hitting things on the road at speed in Summer time.
I have never had a flat tire in my Q [slow leaks yes] in 254,000 miles of driving [13 years], but things mean more to me than money and I never let a tire stay on the car more than 25,000 miles usually 20,000 miles..........even a V/W/Z rated.
Not useful for the real world unless you are a manufacturer trying to test quality control.
The problem with speed rating is you have no way of downwardly adjusting the effects of tire age and stress, oxygen exposure, road temperature, or actual load vs inflation.
Buying a 108 mph is foolish because even though you don't drive 108 mph........the tire when aged may be in reality a 85-90 mph tire in Summer heat after 4 hours with less than 10,000 miles on it.
Why do speed rated tires fail at speeds lower than rating? The car load exceeds the test proceedure or they were made cheaply, good enough to pass the test brand new but not used/worn.
Even though the oem Michelins were V rated they were the best V rated money could buy..............probably exceed the V rating test by 20% because Infiniti felt safe enough to ferry reporters around the Arizona test track at 159 mph 3 to the car with professsional drivers at the wheel [back in 1989 during lauch press introduction].......That was 10 mph greater than the tires were rated for!
If you never exceed the speed limit [75 mph] the minimum speed rating would be should be H rated.........130 mph new maybe 100 mph whenever worn to the bars. That way IF the inflation is too low [even 20 psi if it is well made], the tire won't fail at 75-80 mph in summer heat after 4 hours.
not guaranteed but high probability.
The other factor is load rating [how much weight the tire can support at maximum inflation before exploding] in a similar straight ahead non rigours test..............with a tire less than oem rating all bets are off and WITH a lower than factory speed rating is a double whammy.
OEM tires are designed to wear fast because they know that the tires WON'T meet specs as they age unless they are over built to begin with and very few tires are over built due to competitive pricing pressures. Michelin is the only company that has chosen to over build and you pay for it.
I feel safe with a Michelin H rated as long as the load index is higher than oem. When I must buy a V rated I make sure the load rating is equal to oem.
All about safety margin and strength to survive hitting things on the road at speed in Summer time.
I have never had a flat tire in my Q [slow leaks yes] in 254,000 miles of driving [13 years], but things mean more to me than money and I never let a tire stay on the car more than 25,000 miles usually 20,000 miles..........even a V/W/Z rated.