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Discussion of Boxsters and other Porsches

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Message: Something isnt adding up

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Changed By: grant
Change Date: December 04, 2013 12:23AM

I have no idea, however..Something isnt adding up

I dont have my handy-dandy XLS file here in f-ing cold alberta (-24F anyone, anyone?).

But i dont eyeball a 1" difference. I see a 0.5" radius difference in teh wheel, offset by a decrease in the aspect ratio. The two should partially cancel. actually, with farmer's math, .05 x (roughly) 250mm = 12.5mm = 1/2" = an exact cancel. What size are the actual tires you are putting side by side? I'll wager one is not as specified.

Now, as to TPMS operation.

Even if they ARE 1" off, as long as all 4 tires are the same (different) size, the computer will have no clue. All it sees is rpm's.

As to sizing and theory, plug those numbers into the spreadsheet I sent you and see..... it does all the work.

Grant

Original Message

Author: grant
Date: December 04, 2013 12:10AM

I have no idea, however..

as long as all 4 tires are the same (different) size, the computer will have no clue. All it sees is rpms.

As to sizing and theory, plug those numbers into the spreadsheet I sent you and see..... it does all the work.

Grant