i am new to the site and new to my 2007 grand prix gt. i have already installed an open cone intake and a 180 t-stat. my headers will be here on tues and i'm wondering if i need to do a pcm immidiately or if i can wait untill i drop the pully? also i've heard that the 07 pcm is difficult...do i need to buy a new one from zzp or overkill or can i look locally for one from a different year GP to tune? with these mods is a drop to 3.4" appropriate?
i am new to mods and the last thing i want to do is mess up my daily driver.
i would grately appreciate any help.
thanks!
