this entails an uprated exhaust for better air flow out the engine, and due to the manifold change will require a new inlet manifold and carb needle profiling to suit the new engine set up.
New exhaust purchased from Old Skool Minis (http://www.oldskoolminis.co.uk) based near me in Birmingham. RC40 back box with twin downpipes and a 2 to 1 link pipe and y piece. All stainless steel.
After removal of the previous exhaust I found that a larger back box had been put on the car (possibly to provide better sound) but it provided no real performance gains. (The widening of the system can be seen shortly after the single down pipe on the old system.
Carb in need of some cleaning
A shiny carb set up.
All back in place