If you cut the last pink wire on the back of the odo it takes the 112 restriction off the engine... the odo keeps totalling up in killomerers which is pretty cool... but still, I dont know what other affects this has on the car.. so I dont recommend it.
For that reason when I had an SZ I put that wire on a switch, so if I was going to race I simply switched the wire off !
... i did get an ebay chip for the speedo to, £20, cheep and cheerful, but you pay for what you get.. after two years it doesnt work propper.. Thor Racing is a very good buy!