986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post

texomawaves · 09-21-2009, 05:41 AM

My GPS says I'm doing 70, but my Boxster says I'm doing 75 (5 mph difference). Is there a way to have it calibrated?

The tires are Pirelli Pzero 205/50 ZR-17 on the front, and 255/40 ZR-17 on the back. I feel pretty sure these rims are original stock 17 inch.

09-21-2009, 05:41 AM	#1
texomawaves Registered User Join Date: Sep 2009 Location: Tx Posts: 259	inaccurate speedometer My GPS says I'm doing 70, but my Boxster says I'm doing 75 (5 mph difference). Is there a way to have it calibrated? The tires are Pirelli Pzero 205/50 ZR-17 on the front, and 255/40 ZR-17 on the back. I feel pretty sure these rims are original stock 17 inch.