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#1 |
S2 - Picking it up
Join Date: Feb 2013
Location: London
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Did a very unscientific test at the weekend comparing speed as shown on speedo to GPS on phone. GPS showed 70mph when car indicated 75mph. How do I know which is right!?
Has anyone else compared theirs!? Cheers |
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#2 |
S5, Sport Off, DSC M-track
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It will run about 10% out mate,
My speed limiter comes in at 180mph on the speedo but showing 155mph on GPS
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1979 E24 635csi , 730d work horse , Porsche GT4 |
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#3 | |
CSL Register Uber-poster!
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On an AUTOBAHN my Cecil showed a GPS reading of 174 MPH while the needle was off the clock way past the 180 MPH mark.
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#4 |
S5, Sport Off, DSC M-track
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I think the M3 speedo is calibrated for the standard 18" wheel setup with 225/45/18 and 255/40/18. Mine was quite accurate when it had 18" winter tyres fitted, but is a long way under with the 19s on.
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#5 |
S4 - Getting the hang of it
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Trust the GPS not the speedo!
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#6 |
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#7 |
S2 - Picking it up
Join Date: Feb 2013
Location: London
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Maybe BMW looking out for my licence then... Got surprised by a mobile speed gun on the A13 recently and worried didn't slow down in time but probably not an issue!
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#8 |
S5, Sport Off, DSC M-track
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GPS always reliable
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#9 |
S6, Sport On, Traction Off
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That's a long way out - mine is on the speed limiter at an indicated 168mph and that equates to a GPS 161mph. Standard CSL 19" wheels and correct rolling radius tyres.
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