The principal upgrade in the T-90 is the incorporation of a slightly modified form of the T-80U's more sophisticated 1A45T "Irtysh" fire control system and an upgraded V-84MS multi-fuel engine developing 830 hp (620 kW). The T-90 was manufactured at the Uralvagonzavod factory in Nizhny Tagil, with low-level production being carried out since 1993 and virtually ceasing towards the end of the 1990s for the native market. Less than 200 T-90 tanks were delivered to the Russian Ground Forces before production was resumed in 2005 of an upgraded version.