Photos of the 3 different type of pad fitted to NA/NB MX-5’s. By comparing shape of the pad in the photo to the brakes on your car your car you should be able to tell which type your car has.
1600 Brakes
Application = NA B6 Engine
Front
Pad Length/Width = 110mm/45mm
Disc Diameter = 235mm
Rear
Disc Diameter = 231mm
Pad shape
1800 Brakes
Application = NA BP Engine/All NB except with sports & hard suspension
Front
Pad Length/Width = 110mm/54mm
Disc Diameter = 255mm
Rear
Disc Diameter = 251mm
Pad shape
“Big” Brakes
Application = NB F/L “Sport” & some special versions.
Front
Pad Length/Width = 123mm/54mm
Disc Diameter = 270mm
Rear
Disc Diameter = 276mm