these headers are for a LQ9 (6.0 or 5.3) engine. I brought them for my firebird for my turbo kit but decided to use the stock LQ9 manifolds cause of the heat a turbo can produce. Didnt wanna chance cracking them. They are polished as you can see in the picture and like i said never been installed im letting go for 250 + shipping. The brand is OBX. These suppose to be a direct replacement of the stock manifolds and has no egr flange on it. Below is pictures of the headers next to the LQ9 manifolds

 

what is the tubing size? 1 3/4?