hardened valve seats

[Dave Williams]

-> Does anybody of you know what (generally available) material
-> I can use for unleaded-fuel-valve-seats?

 Cast iron works just fine.  The bronzes appear to work fine too.
Beryllium/copper is the material of choice for very high output engines,
but it's hard to obtain small quantities of appropriate shape.

 Inconel (trade name for high-nickel alloy) is a wonderful seat
material, but one of its characteristics is very low expansion, leading
the seats to fall out unless they're the screw-in type.  They're
sometimes used for large Diesels.

 Stellite is a popular replacement seat material, but Stellite seats are
sintered to near-net shape since they're very hard to machine.  Stellite
is what most machine cutters used to be made of.