These are the most common sizes and shapes of the XR-1 mufflers. The oval is the most popular for street cars because it doesn't hang down as far as the others and has more packing material. After all ...
It's been a few weeks since I installed the Borla cat-back exhaust on my 1991 brg Miata (1.6 liter) and the tone is phenomenal. This video covers sound clips, start up, revs, etc. and installation ...