I've found that at the very least my puppies all seem to pee 5-20 minutes after eating. I've had some that will pee and poop in that time, and others that will only pee, but will poop a couple hours later. Twice a day for poop sounds pretty normal to me, especially for a puppy on a higher quality diet (it seems like the purina/pedigree puppies in my classes poop 8-10 times a day! D: ) Every puppy is different. As long as you get a good feel for when he is likely to have to go and you let him out to do his bathroom breaks in the grass where they should be, I feel like you're doing well.
Some puppies that tended to take a long time, I would be patient with a reward them as soon as they go. It takes patience in the beginning, but it helps them get the idea that the faster they do their bathroom duty outside, the faster they'll get a nice tasty treat.