DD9 front rear caliper difference.

[James-i9xfz]

Hello, Looking into using Aston Martin DB9 calipers for a front brake conversion. The fronts and rears look identical but have different part codes (below). Does anyone know the actual differences? Piston size, brake disc width? Any help is appreciated thank you.

Front (DB9):
20.8427.03
20.8427.04

Rear (DB9):
20.8429.03
20.8429.04

[Phuketpaul]

I'll check the exact sizes tomorrow but from what I remember:

Fronts have much larger pads, and larger pistons
Fronts have a larger gap between the two sides for larger discs
The mounting holes are the same distance

[James-i9xfz]

Hi Paul, thank you that would be appreciated.