6 replies to this topic

[stardude]

hi, just wondering if i need to modify my speedo if i change to 10" wheels?

thanks

adam

[Tomf]

Yes.

[JetBLICK]

U see, i think this is a myth. We stood one of my 10's next to my m8s 13 the other day and the 10's where actually bigger! The 10's are on 165/70's and the 13's on 175/50. The only difference would come from the tyre flex in the 10's. Any error on the speedo would be very minimal, not worth paying £45 for anyways

[Matrix]

It's more to do with the diff ratio!

[stardude]

It's more to do with the diff ratio!

ehh?

[Ethel]

10's are indeed much the same size as 13's with 50 series tyres. 12's tend to be bigger.

You don't 'have to' modify your speedo, it won't fail an MoT.

Check out GuessWorks threads 'n site for more info on speedo gearing you probably only have to swap the pinion to get an accurate speedo again.

[stardude]

i have spoken to guessworks, and as i will be going down onto tens at the same time as i change the clocks over to newer nippon seiki 3 clock, all i need to do to get the speedo to read correctly is to change the speedo drive on the side of the gearbox and fit a new speedo cable. its easier, quicker and cheaper than sending it to be recaliberated. SORTED! thumbsup.gif