P0421 is it possible to link out?

[RickLS7]

Black tape was of course, a joke.

So he's going to charge you £300 just for re-flashing your ECU with a map not specific to your car and maybe not even exactly the same.  A car won't be harmed on a rolling road as long as it's up to temperature, the whole industry has taken off the last 10 years and thousands get their cars tuned properly on rolling roads every year.

Several guys on here have had their Boxster's re-mapped, I think EDC was one of them.  Send him a message.