993 MPH speedo reading vs OBC computer reading
Discussion
stick a sat nav on the dash or as I do now use a speedometer app on my phone and then you will know your true actual speed. Typically your Porsche speedo will over read by 10%. Good for speed cameras. I do this with all my cars to get a solid baseline. My truck is almost bang on. The Cat under reads. 189 through a speed beacon against 184 on the speedo
Edited by SRT Hellcat on Thursday 14th September 23:36
SRT Hellcat said:
stick a sat nav on the dash or as I do now use a speedometer app on my phone and then you will know your true actual speed. Typically your speedo will over read by 10%. Good for speed cameras. I do this with all my cars to get a solid baseline.
I was thinking of that but was not sure if it would be more or less accurate. Do sat navs really give the most accurate readings? Probably obvious but I'm not a GPS expert!GPS measured speed is quite accurate when travelling in a straight line at a steady speed in an open area where the GPS aerial has a good "view" of the sky. They're typically not that accurate in urban areas where there's a limited view of the sky and signals are bouncing off buildings (called canyoning) or if your speed is changing.
Dammit said:
My 996 does this as well- needle speed is 5mph under digital speed. It's annoying, but I don't know how to fix it. Neither do I know which is correct!
Thing is, the needle on a 996 is fecking useless as it's calibrated in a stupid way. I don't use it for at-a-glance checks at all.Gassing Station | Porsche Classics | Top of Page | What's New | My Stuff