thanks gareth and stu!

so the old - you can mess around changing air filters, exhausts throttle bodies etc and it will be ok as its fuel injection and has a lambda as is often put about - is erm pretty much crap?

ah right so thats another one.... ok thats live mapping detailed but on a chip for example... where you dont get the feedback of what the car is doing etc... is it just from experience that you could make assumptions on what to do with the map?