Same here, that's the figure in my Super Decathlon's AFM. Interestingly, my Lycoming manual simply states: "Engine is warm enough for take-off when the throttle can be opened without the engine faltering."
I've flown other Decathlons where someone has changed the oil pressure gauges over the years. One has no marking so those pilots who call out "temps and pressures in the green" and then carry on without thinking have me thinking. Another has 160 deg F as the bottom of the green - one winter morning an instructor sat on the ground for almost all of his student's one hour lesson waiting for it to warm up!