Hasn't this done the rounds before? Remapping cannot be detected unless they have the time to download the map and compare them side by side. Anyway, why is a remap illegal? Afterall it's only the factory parameter tolerance been changed to improve fuelling, not changed to the point where emissions are running high, it's the total opposite! If it goes that far and makes a good road car illegal then I will not bother MOTing it and just leave it as an out and out track car as that is where I enjoy it the most. Trailer will be it's road wheels