Some bored TBs we've recently done for two 2.6 twin screw Jaguars (XJR and STR) and an XF SV8, also soon to be converted to twin screw. The whole unit is disassembled, bored and rebuilt with a custom butterfly.

On the earlier ecu TBs we achieved 83mm, and on the larger style one (2006 and later) we achieved 84.5mm, up from the standard 75mm. Thought it may be of interest to those subscribed to this thread.