http://blog.hgomez.net/2015/02/26/CentOSRHEL-and-up-to-date-Subversion-and-Git.html

yum remove git*
yum clean all

/etc/yum.repos.d/wandisco-git.repo

[WandiscoGIT]
name=Wandisco GIT Repo
baseurl=http://opensource.wandisco.com/centos/$releasever/git/$basearch/
enabled=1
gpgcheck=0