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Old 12-07-2009, 03:39 PM   #11 (permalink)
GTRFAN
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Quote:
Originally Posted by Majestik View Post
When I'm at 109kmph, I'm actually doing 100kmph.

I'm starting to think Nissan got the tyre specs wrong and the overall rolling diameter is whats causing the innacuracy.

The thing is, if the indicated speed is higher than the actual speed, then the rolling diameter (circumference) is slightly too small (and not rolling the car the distance the speedo thinks it's going).

To fix this we can either get taller side % profiles, but I'm not exactly going to do this as the side wall profile already looks too fat for an 18" rim compared to other cars.

Hopefully Nissan can adjust the speedo calibration at a service? I'll look into this when I get 19" and new tyres in the profile I want.

Just my 2c worth of daily rambling
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