I am using git as version control.
I have setup /var/git/myproject.git directory with permssions to

wwwrun:developer and chmod 770

we have 3 developers who commit to repo. they all in developer group.
now when anybody commit the folders in objects get created but now they have permission as rwxr-xr-x.
how i can make sure that permission remains rwxrwx---

where should i made changes?