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Speedometer correction factors

Indy555

Re: Speedometer correction factors

Post by Indy555 » Sat Feb 18, 2017 9:00 am

petroscf wrote:Indeed!!
And based on a couple of comparisons I've done with gps, it seems you're right!
However, isn't all this also depending on wheels diameter?
Yes. You're right. But most wheel dimensions that fit the e21 are comparable in scope.
So it's correct to have always an eye on the factory fitted wheels for Your e21...

175/60R13 : 1.63m
185/60R13 : 1.67m
185/50R14 : 1.63m
195/45R15 : 1.68m

Just a few....



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petroscf
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Re: Speedometer correction factors

Post by petroscf » Sun Feb 19, 2017 4:59 pm

My car initially, as a 316 used to wear 165/13 which means I guess a profile of 82? Or 80?
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Jeroen
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Re: Speedometer correction factors

Post by Jeroen » Tue Mar 07, 2017 8:12 am

Stock size is, I believe, 185/70-13, diameter 589mm, or 165R13 (80% sidewall), 594mm in diameter
Regards/groeten, Jeroen

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petroscf
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Re: Speedometer correction factors

Post by petroscf » Tue May 09, 2017 11:24 am

mcjjordan wrote:found a lovely calculator for working out variants

http://johnmaherracing.com/calculators/ ... alculator/
As this is really lovely, shouldn't we add this to the "all kinds of useful calculators" thread, perhaps?
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Re: Speedometer correction factors

Post by Jeroen » Tue May 09, 2017 8:23 pm

We had one in there but the link was now dead so I put this one in, thanks!
Regards/groeten, Jeroen

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Re: Speedometer correction factors

Post by petroscf » Wed May 10, 2017 2:05 pm

:thumbsup
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Re: Speedometer correction factors

Post by petroscf » Fri Jun 09, 2017 2:25 pm

Jeroen wrote:We had one in there but the link was now dead so I put this one in, thanks!
Today tried a couple of times to reach this link, it doesn't seem to work, hope it is only temporary
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Re: Speedometer correction factors

Post by petroscf » Fri Jun 09, 2017 3:12 pm

Found this one instead, seems ok:

http://www.cargister.com/calculator-gear-ratio
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Re: Speedometer correction factors

Post by Jeroen » Fri Jun 09, 2017 8:15 pm

Thanks I'll update the link once again haha
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Re: Speedometer correction factors

Post by petroscf » Fri Sep 08, 2017 10:46 am

The speed correction factor should be taken into account when calculating the distances shown on the odometer?
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