Valve seat materials

[Psucamper]

Currently refurbishing six T4 2000cc cylinder heads. My carbide Neway valve seat cutters are quite old and have ceased cutting well. Time to renew. Looking at the specs for new blades, I find two types. One for "soft" seats and one for "hard seats". The carbide is the same but the serrations are different. Our AC heads use metal inserts into aluminum. I would guess that "soft" would be iron/steel and "hard" would be something like stellite or sintered something. Prefer not to guess.
Vendor says the exhaust seats are "hard" and the intakes are "soft".Well..maybe yes,maybe no. Anyone have the answer? Bob L.

[Amskeptic]

Currently refurbishing six T4 2000cc cylinder heads. My carbide Neway valve seat cutters are quite old and have ceased cutting well. Time to renew. Looking at the specs for new blades, I find two types. One for "soft" seats and one for "hard seats". The carbide is the same but the serrations are different. Our AC heads use metal inserts into aluminum. I would guess that "soft" would be iron/steel and "hard" would be something like stellite or sintered something. Prefer not to guess.
Vendor says the exhaust seats are "hard" and the intakes are "soft".Well..maybe yes,maybe no. Anyone have the answer? Bob L.

VW used sintered seats. Question is, how many original seats are to be found in our cylinder heads?
You could ask a high-volume refurbisher like RIMCO, I reckon, just a phone call away.
Colin