It will make some difference, but i truly reccommend changing up your routine a little. Cardio is also important to muscle growth because it gives you more stamina to be able to do more chin-ups. Instead of just that, run about 30 min to an hour before situps. It will feel better and you wont get to bored. Now if you want muscle i would also reccomend weights. Once again to swicth it up and not to bored of just the same thing over and over agian. And dont forget to eat right with protien such as chicken breast with fruits as well. if not, then all that work will be for nothing.
Do them slowly for one set and on the second set do them with a one and a half movement. Go down or up half way, back up or down and then a full one.Also decrease the time between sets. And make sure you are taking in sufficient protein to allow for recovery, repair and growth of new muscle tissue.