Chris Todd is very up to speed on Supercharged Foci.
Kester has a Supercharged ST170, Ian Allen is a regular customer with a Powerworks charger-ed ST170. He's recently swapped the Turbo on a Focus RS engine for a 'charger and he's got another customer from Bristol way who has a supercharged 2.0 litre pushing 300-odd brake. Might be one more as well but the point is made - he knows his stuff about them and what needs doing to fit one effectively and safely
Torque of the Devil - 01895 206777