18" wheels vs speedo

[vxer]

Hi guys,

Since my RX7 has 18" wheels, does this mean my speedo will under-read slighty?

Anyone know by how much? Can it be corrected for via PFC?

Ta, Paul.

[Fish]

If you look under the Wheels section, there is an excel spreadsheet that will work it out for you.

Just input your tyre sizes and there you go.

Fish

[vxer]

Ta muchly!

Cheers, Paul.

[chopper]

my 18\'s work out at about 2mph difference. When im doing 28 im doing 30 basically