Anyone run an intake without heat crossover in winter?

How long does it take for the engine to warm up and start putting out heat? Right now with the old 340 iron intake, and the previous smog qjet intake, the heaters starting to work within a few minutes. I'm just trying to keep some heat in the cab when old man winter hits.lol. Can remember running an old Chevy truck with Rpm intake,roller rockers,geardrive,headers etc. Once it got coolout, that motor wouldn't hardly warm up no matter what thermostat, radiator, I put in it