If I deliberately increased my total rolling wheel diameter by fitting a larger wheel size without reducing my tyre aspect ratio so I could increase my gearing could I alter the speedo with VAGCOM to compensate. My 1.8 non turbo spins at nearly 4000 RPM at 80 and seems ungdergeared in most circumstances. I can keep up with traffic and negotiate most roundabouts without needing to change down below 4th unless the speed drops under 20MPH. No, I'm not a mobile chicane and the engine isn't labouring it just pulls the higher gears really easily. I think 25MPH/1000RPM instead of the 21 I get would be more suitable.

No, not with VAG-COM. You need to edit the EEPROM memory in the dash cluster with a tool like VAG-TACHO.

J