The infernal combustion engine continues to make increasing demands on the valve seat insert as power outputs are increased, the use of alternative fuels proliferated and better fuel economy sought. These demands are being met by the latest developments in sintered powder metal valve seat insert materials and design. The developments described are; the incorporation of a high temperature solid lubricant into a heat and wear resistant sintered alloy steel which is particularly effective in dry running environments; a cobalt free, cost conscious high speed tool steel based sintered alloy possessing excellent thermal conductivity for use in arduous applications including the new alternative fuels (natural gas, L.P.G. etc.) and a design of sintered valve seat insert for use in the inlet position which induces a swirl action into the ingoing fuel/air mixture leading to improved fuel economy.