Speedometer accuracy (cross post on 993 forum)?
04-06-2010, 11:21 AM
#1
Nordschleife Master
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Speedometer accuracy (cross post on 993 forum)?
Is your speedometer reading accurate? Mine seem to be running 10% too high according to my 9500ix radar detector. Tires are PS2s 235/40 and 295/30 on 18" rims...I would have thought with these slightly larger diameter tires (compared to the factory 225/40 and 285/30) the speedo would read too low, not high. Or do PS2s run small? 
04-06-2010, 12:30 PM
#2
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The digi speedo on the 993 Turbo is dead-on compared to my Garmin GPS. The Turbo's analog shows about 2-3 mph faster than actual.
On my 987S both speedos are 2 mph faster than actual vs. the Garmin.
On my 987S both speedos are 2 mph faster than actual vs. the Garmin.
04-06-2010, 02:02 PM
#4
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Same tires as yours and my GPS, speedo and digital all match. No error rate on mine at all.
On my cab, all three read differant. They were way off.
On my cab, all three read differant. They were way off.
04-06-2010, 02:36 PM
#5
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