I've had some experience of tuning my Subaru's over the years and now have a MY08 120d 177BHP M Sport. I think this is the "E90" engine.
Searching around here I see a remap might extract 200 - 225 BHP. Further to that do these cars respond well to a CAT replacement (or the diesel name for the same) then a custom remap?
The one thing I'm confused about is if these 'CATs' legally need to be fitted for MoT purposes at this time (understand rules may change in the future). What I've read suggests they might not be required yet but confirmation would be good. Also assume there is only one 'CAT'.
Assume the stock air filter also needs a drop-in replacement?
Interested in finding the 'good tuning combination' for these cars and asking the experts is always the best start....
Sorry for all the newbie questions from a first time Diesel owner!