Flowmaster= great sound, drone(2 chamber), and head ache
Mac= decent sound, rust, and moderate drone
Magnaflow= low quiet rumble, quality, and no drone or head ache
That is my experience.
As far as HP, I don't think it matters unless your motor is pushing 400+ HP. Anything is better than stock.
Just FYI
------------------
1998 Mustang Gt
C&L 80mm
Steeda Underdrives
Steeda Tri-Ax
Magnaflows
|