Boston’s Bang Camaro broke into the mainstream with the Guitar Hero II hit “Push Push (Lady Lightning),” and the buzz spread quickly to create an international fan base. A metal band with indie leanings and arena rock stage presence, this quintet can grow to as many as twenty at any given show. Guest singers are generally members of various indie rock bands from around the Boston area, forming a choir of lead singers and turning out a glam-rock gala. Shows are fast becoming legendary, consistently selling out dates and ever-expanding the group’s size and scope. Now with the release of their self-titled debut on Black Sword Records, Bang Camaro revs up for a victory lap with a fall tour that comes to the Showplace Theater on Friday (Sept. 7). The show starts at 8pm and support comes from Johnny Nobody.