For a number of years MGA 1500 owners wanting to convert their front drum brakes to discs have had major problems sourcing MGA brake callipers.  Most conversions have resulted in the use of a number of MGB suspension parts and MGB callipers.  The lengthy conversion also involves adjustments to the camber and tracking.

At last a new MGA calliper adapter plate is on the market, available from Moss.  The plate mates an MGB calliper with an MGA 1600 brake disc and an MGA 1600 hub.  And the good news is that it fits the 1500 and takes only a couple of hours to install.  Total cost of the parts, including an outright purchase of reconditioned MGB callipers is about 500, as follows (2011):

2 Adapter plates 


2 MGA 1600 brake discs  79.90
2 MGA 1600 hubs 141.90
2 MGB brake callipers 79.90
2 Sets of brake pads 25.00
2 Hub oil seals 3.50




2 Sets of hub bearings may also be required, depending on state of existing ones.

The other good aspect of this modification is that, with the exception of the MGB calliper, work description, pictures and diagrams are contained in MGA workshop manuals.

The following pictures show the stages of conversion for an MGA 1500 that has already been converted to centre lock wire wheels. 


All the parts required to convert an MGA1500 drum brake car (with wire wheels) to disc brakes

Existing drum brakes
Stripped down to the basic MGA stub axle
Calliper adapter plate bolted in place
Brake disc and hub assembled
All items bolted in place.  Check that the disc runs central in the calliper slot (may need to shim).  Check that the flexible brake hose is not stretched at limits of steering lock and does not foul any moving parts.  Job done.  Now the other side and bleed the system.