Thread: Check your speedos.

Yep, most car Speedo’s read 5 and some even 10% high. I think I read somewhere that it came about through litigation avoidance in countries where the manufacturer could be sued for speed related fines, so they built in a margin.

I put a VDO programmable speedo in my old Landy and replaced the mechanical cable with a Hall effect sensor off a later model. On the VDO, I set the pulses per km to 10% higher than actual to slowly claw back my RUC costs... At 100k’s indicated, it was bang on 110.