Disco tyre Q - confused

champ69 · Posted: Thu Nov 16, 2006 5:35 pm Post subject: Disco tyre Q - confused

I swopped my disco steels/205/80/16 for some alloys 235/70/16. Have used a tyre calculator and that says that at 70, they are the same (well, 0.1mph difference), but I could SWEAR that the car sits higher, AND tha the acclleration IS slower, ie that it has more 'legs' and the gearing DOES feel differnt. AM I imagining this ??

Mr Tyre · Posted: Thu Nov 16, 2006 9:25 pm Post subject:

Yes, if there is any difference between them in theory it will only be a couple of mm or so.

:) · Posted: Thu Nov 16, 2006 9:52 pm Post subject:

Could the tyres actually be 235/80/16's?

Put a straight edge across the top and measure to the ground (it's not 100% accurate but will do as a quick check):
235/70/16 should measure about 735mm
235/80/16 should measure about 782mm
Quite a difference!

Out of interest 205/80/16 measures 734mm
--
Tim.

Mr Tyre · Posted: Fri Nov 17, 2006 7:11 am Post subject:

If the speedo is 0.1 different than that will be 205/80R16 against 235/70R16.If the calculation was different by around 6.5% than that would be for 235/80R16. 235/80R16's won't fit a standard ride height Discovery without work.Some make for make 205/80R16's are the same diameter as each other.

The Pikester · Posted: Fri Nov 17, 2006 9:19 am Post subject:

Especially if your new tyres are remounds? Just as an example, the 35" Simex copies on Steves Challenge truck (remoulds) are 1.5 inches (4cm) bigger in diameter than original simexes. That was measuered side by side.