I like using cake mixes as oppose to scratch cakes and was wondering about enhanced mixes. I would love to get a little tighter crumb and was wondering if I could add just a cup of sour cream to achieve this?
Considering that DH has pudding already in the mix it would seem unecessary to add more pudding on top of that. Any suggestions?
Maybe milk or buttermilk instead of water.
Would a cup of sour cream alter the taste?
Would an extra egg help?

I have used this extender recipe with success for carving topsy/turvy cakes. It comes out a different texture than a box mix, but it was moist and everyone raved. I was the only one who knew it wasn't completely scratch
http://www.cakecentral.com/cake_recipe-1977-Cake-Mix-extender.html

HTH

I tried this and it is really good and the crumb was tighter

I tried this and it is really good and the crumb was tighter