A process for treating hydrocarbon feed in a furnace, the process comprising: (a) heating hydrocarbon feed, (b) adding water to the heated feed, (c) adding dilution steam to the heated feed to form a mixture, (d) heating the resulting mixture and feeding the resulting heated mixture to the furnace, wherein the water in (b) is added in an amount of from at least about 1% to 100% based on water and dilution steam by weight.