So does the n/a and SRT both have 67mm TB's? Rob suggested that I get something bigger than the 74mm that is stock in my V8. I am wondering what is the ideal size? I noticed that the Chysler Hemi 5.7 and 6.1 both come stock with 80mm and those guys are jumping up to 90mm in their n/a engines. I am thinking 78-80mm might be good for me. If I go with Max bore and the mod from MB world I should have the flow of 80-82mm. I am getting a bse line dyno this week and have a whole list of reasonably priced mods that I am hoping will get me to or past a n/a 55.