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Old 06-05-2008, 07:15 PM   #91 (permalink)
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CapriRacer -

Originally Posted by CapriRacer View Post
Progress Report:

I may have found something pertinent:

SAE 800087 - The Effect of Inflation Pressure on Bias, Bias-Belted, and Radial Tire Performance - Coolier / Warchol - Feb 1980.


The net effect is that the tires that go onto new cars are somewhat different than what you would buy on the open market (sometimes, a lot different.) Typically car manufacturers want tires with lower rolling resistance (in order to meet CAFE requirements) and RR is bought by sacrificing wear and / or traction - especially wet traction.
I have read this elsewhere. The upshot of this is that if you can, getting the same tires that the car came with will get you LRR without having to do much homework.

So anyone who tells you that the car manufacturers buy tires from the lowest bidder and that's why they don't perform well doesn't know what he is talking about.


There are many other types of lab tests - Step Up Speed, Plunger Energy, Bead Unseating, etc. - and each of these is designed to quanitify a particular aspect of tire performance.

There are also many on vehicle tests - but these are pretty expensive and controlling ambient conditions is impossible, so they become problematic.

But the point I want to make here is that the industry standard SUL test remains the backbone for tire durability - and more to the point, tire pressure is not one of the items that becomes a testing variable. The bursting pressure of a new tire is an artifact of the design based in these lab tests.
This is interesting. Once again, as Ecomodders we are using a component of the car (the tires) "outside the test domain".

Based on your description of the test, I am happy with my choice of "inflate to the max inflation rating". Because of this, however, I also think I have to invest in an accurate tire gauge.

What's the most accurate gauge out there? Can a gauge be "calibrated"? If I knew the % error, would that error be linear or ?!?!?!?!?



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