In the US, a 4lb pork roast is usually cooked for 3 hours or approximately 12 to 15 minutes per pound. This means that a 4lb roast should take about 2 hours to cook. This is not a real easy roast to cook because it tends to be very tough. For this reason, you should either cook it on the bone, or if possible, cook it in a water bath.
4 lb pork roast can be a lot of food for one person. This is why it’s important to cook it properly. If you cook it for too long, it can become tough and dry. If you cook it for too short of a time, it can become too rare.
It doesn’t take too long to make it which makes for a quick and easy dinner. For instance, a 3 lb roast, will take about an hour to cook at 20 minutes per pound. This roast pork loin recipe is so simple to make and what’s nice is that you don’t have to do much to it to make it seem like you worked on it for hours.
At 145 F, the center of the roast may still be slightly pink, but it is safe to eat. Pork roasts, as large cuts, will continue cooking after they have been removed from the oven, rising upwards of 10 degrees more during resting.