wammers said:

Yep silly me wrong way round. Incidentally and just for information. Any vehicle manufactured after i think 2001 MUST have a speedo that reads - 10% +0% at 30 mph. It is illegal if it doesn't. So if you have indicated 30 mph you can be doing 27,28,29 or 30 but not 31. On vehicles made before that date the allowance is i think, + or - 10% at 30 mph. So at an indicated 30 you could be doing between 27 and 33 mph.That is why speed cameras have an allowance of + 10% +2mph. So should not go off until you exceed 35 mph. Because speedo's before 2001 could indicate 30 but you could be doing 33. Think the regulation was brought in in a bill in 1999 but only ratified in 2001. To give manufacturers a chance to introduce it.
Think thats right but of course like many things passed on by rumour could also be a load of horse ****.

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p38on22s said:

mine came with 235/70/16s on and now running 285/35/22s and when i run any sat nav in there the speedo is the same as the speed on the navs

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jonny427 said:

I have 255/60/18's on my 98 p38, these were on the car when I bought her. They will cause the speedo to under read.

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