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Old 06-05-2008, 08:14 PM   #93 (permalink)
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Originally Posted by AXMonster View Post
Thanks Capri. I never worked on the rubber end of car design, just the performance & emissions end

So, I can't just say that my car has a corner weight of 228kg and the tyre's max loading is 387kg..... so the sidewall maximum of 51psi can't be scaled up to 72psi due to the loading being only 60%???
Shame its not that easy!
Plugging 36psi into the equation instead of 51 gives a maximum of ......... 51psi based on scaled pressure due to less than maximum loading!! Wierd!!

Edit - Have I got this back to front?? The tyre's maximum loading increases with increasing pressure.... but does its maximum pressure decrease with decreasing load???
You've worded the question a little funny. I think it would be better to state it this way: If you are using something less than the maximum load carrying capacity, then the pressure in the table is a MINIMUM pressure for the indicated load.

And it is common engineering practice to underutilize a product - and this is probably more true for tires as the load tables are predicated on some pretty ideal conditions - smooth roads, ambient temperatures below 100F, etc. - and this is substantiated by a lot of statistic gathering that says that most of the tire failures occur in hot climates.

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