speedo accuracy
Posted:
Fri Mar 31, 2006 7:32 amby combatcqb
When all of us change wheel/tire diameter, we know that our speedometer won't be accurate anymore. The ECU assumes stock tire diameter to calculate speed, is this a simple change in the ECU? Or is this part of the whole rom decoding adventure? This also affects logging as well.
I know this might be trivial in the grand tuning scheme, but just something I thought was useful.
Posted:
Fri Mar 31, 2006 4:32 pmby gethin
when you go to different tire sizes you also change the profile, so the bigger the wheel/tire combo the smaller the profile. This keeps the rolling radius the same (probably a tiny variation).
If you stick on a wheel tire combo not designed for your car then you will get errors.
Posted:
Mon Apr 03, 2006 10:38 amby Jeramie
gethin wrote:when you go to different tire sizes you also change the profile, so the bigger the wheel/tire combo the smaller the profile. This keeps the rolling radius the same (probably a tiny variation).
If you stick on a wheel tire combo not designed for your car then you will get errors.
I think he was asking if you could correct the speedo through the ecu.