If there is no "Alcon" typing on your callipers you should have the 1-piston-floating-callipers of the standard brakes with 240mm discs.
The standard brakes had plain discs, the sports brake package had drilled or grooved discs of the same size.
These callipers were also fitted to the MGF, so to answer your question regarding the pads. There might be other brakes for the MGF though, so the 240mm should be the indicator.
If you like to improve your standard brakes without going the Alcon or AP way this might be interesting:
http://mgfmania.com/
They offer kits containing 280mm discs and adaptors to reposition the callipers, that fit p&p to the MG and resulting also to the Atom.
As Alcons are hard to get these days this might be a good choice front and rear to start with.
There are also other companies offering such kits, however at mgfmania you can choose between different disc brands and designs (plain, grooved, drilled, both).
If there is no "Alcon" typing on your callipers you should have the 1-piston-floating-callipers of the standard brakes with 240mm discs.
The standard brakes had plain discs, the sports brake package had drilled or grooved discs of the same size.
These callipers were also fitted to the MGF, so to answer your question regarding the pads. There might be other brakes for the MGF though, so the 240mm should be the indicator.
If you like to improve your standard brakes without going the Alcon or AP way this might be interesting:
http://mgfmania.com/
They offer kits containing 280mm discs and adaptors to reposition the callipers, that fit p&p to the MG and resulting also to the Atom.
As Alcons are hard to get these days this might be a good choice front and rear to start with.
There are also other companies offering such kits, however at mgfmania you can choose between different disc brands and designs (plain, grooved, drilled, both).