The StopTech ST-40 caliper is designed to use a pad from various Porsche models including the 944 Turbo, 1991-1994 911 series, 1992 968 and 1986-1991 928.
Numerous manufacturers make different compounds from street to full race applications for this pad shape. The Friction Materials Standards Institute (FMSI) establishes a numbering system for pad shapes in virtually every vehicle sold in North America so that cross referencing the various OE part numbers can be vastly simplified. Some pad manufacturers have a cross reference between their numbering system and the FMSI number, but others still do not provide such a tool.
The FMSI number for the pad used in the StopTech ST-40 caliper is D372.
Over the years, Porsche has consolidated certain pads with slightly different backing plate shapes. Though these pads that Porsche consolidated will all fit in a Porsche caliper, they will NOT all work in the ST-40 due to the tighter tolerances of our bridge and pad retaining system. Other FMSI numbers used for similar pads are D447 and D609. While this reference may work with some pad suppliers, only a D372 pad is assured of fitting the StopTech ST-40 caliper.
Here is a list of manufacturer's part numbers that will fit our caliper (X denotes pad compound):
EBC: DPX767 (uses D447 as FMSI cross reference)
Ferodo Race Pads: FCP560
Ferodo Street Pads: FDB560
Hawk Performance: HB141X.650
Performance Friction: 0447.XX.17.44
Raybestos Race Pad: R609