I've fed that years ago. Remember that puppies need to eat more than adults because they are growing -- lots of calories, and they have more energy than adults. Between the two, 4 cups may or may not be enough. It depends on how big your dog is likely to be as an adult, and how much energy he currently is expending.
At this age having a little extra on him is not a bad thing at all. If you can see his ribs, or if they are right there when you feel them, give him and extra 1/4 cup at each feeding. If after two weeks he does not seem to be filling out any more, bump another 1/4 cup.
Jenna, RN CGC & Babs, CD RA CGC HIC
Heidi, RA CGC
SG3 Odessa, SchH1, Kkl1, AD
Ninja, RN CGC & Milla, RN CGC
Joy, Star Puppy, RN CGC
Dolly CGC & Bear CGC