So glad I found this thread.
I have 2007 5.4 4x4 and the classic exhaust manifold leak on both sides. I will have a 3" SI/SO magnaflow muffler. Would there be any benefit to long tube headers, specifically pacesetter? Adding high flow cats from magnaflow? Y-pipe staying close to stock position and all piping 3", if I would do this. Looking for good overall power, not high RPM only power. Also tuner would not come for about a year.
Last edited by chayes627; 04-29-2014 at 10:02 AM.