Quote Originally Posted by fst4dr View Post
actually you are only supposed to open the screw while filling not while running the car and the air will make its way out of the open rad just fine. look at the system the top of the rad is higher than the brass screw so........ Guess where the air will go!!! you got it champ to the top of the rad where there is the.......... Open rad cap!

im not so sure about that. read this. http://www.grandprixforums.net/engin...ting-8778.html