My Type R speedo is slightly out, it thinks I am going faster than I am and so also the mileage is calculating more mileage than I am actually doing. I am running 18s but would not have thought that this would be an issue?

Have anyone else had this on a Type R?

 

Most are slightly out, as a rough estimate most are 10% out and will read higher than your genuine speed. When i used to import / SVA your true speed could be as low as 57mph whilst displaying 70mph and that'd still be a pass

 

Your kidding?! The only reason I noticed was my boyfriend was in front of me in his R33 Skyline and we were in a 50mph roadworks zone on the motorway and he pulled away from me although I was at dead on 50mph. I think mines about 5mph out at 50mph and is more out the faster I go. As his is an import also and converted to mph I assumed something may be wrong with mine. We did 160 miles and my Type R calculated 180 thats so annoying!!

Thanks for your reply

 

What size tyres do you have on?

If 18s they should be 205 35 for a correct reading. As it came with 16s on 205 45. So 17s should be 205 40. I hope that makes sense.

 

You'd be suprised how inaccurate some speedos are! I recently sold a 2011 VW T5 camper that was around 15% out on standard steel wheels so not modified at all.
You could try altering it by relocation of the speedo needle but you'll need to be careful not to ruin it. It may be worth getting a cheap gps unit in the car or just use one to know what higher speeds you can run at. eg if your car shows 77mph at a true 70mph then you know you can safely run at an indicated 77mph

 

as above your tyre / wheel size changes it

http://www.tyresizecalculator.com/ty...ror-calculator

so either you need to change tyre size or get a recalibration done mate

 

I drive loads of different makes and models. There all out. Comparing with a sat nav. Anything between 5 and 10mph. Its almost impossible to have them spot on because things like tyres wear out so the rolling radius changes

 

Speedos generally tend to be about ten percent optimistic. That's a designed feature to guard against speeding. The faster you go the more it's out.
Regarding the milometer, I don't think that correlation transfers accordingly.
Best way is to check the mileage against a measured distance. Even though the speedo is optimistic the mileage should be accurate.