Short tails are a direct, bolt on replacement for the stock muffler. I do not consider the sound loud at all. It is more aggressive, but higher pitched than a cat back with resonators and mufflers. Our cars do not really get "loud" until the stock cats are replaced or removed.
You won't damage the motor. I'm not even sure an axle back would change the AFR.
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Competition Clutch|Fast Intentions|Maxbore|NST|Setrab|Stillen|Tomei|Uprev| Z1
Avant Garde|SPC|Stance|Whiteline
Aerojacket|Seibon|Tanabe|TRS|TWM
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