Exhaust System Buyer's Guide: Cat-Back vs. Axle-Back vs. Full System

The exhaust system is where performance meets personality. Nothing changes the character of your Challenger like a new exhaust. But the terminology can be confusing — here's what you need to know.

The Three Levels of Exhaust Modification

Axle-Back Exhaust ($400–$900)

An axle-back replaces only the mufflers and tips — everything from the rear axle back. It's the simplest exhaust mod: two bolts per side, 30 minutes with basic tools, and no impact on emissions equipment.

Best for: Sound improvement on a budget. An axle-back typically adds 3–8 HP but transforms the sound character.

Cat-Back Exhaust ($700–$2,000)

A cat-back replaces everything behind the catalytic converters — mid-pipes, resonators, mufflers, and tips. This is the most popular exhaust upgrade because it offers the best balance of sound, performance, and legality (catalytic converters stay in place).

Best for: Best all-around upgrade. Expect 10–20 HP gains plus a dramatic sound improvement. The increased pipe diameter and less restrictive mufflers make a real difference.

Full Exhaust System (Headers + Mid-Pipes + Cat-Back, $2,500–$5,000+)

A full system adds long tube or shorty headers to a cat-back setup. This is where the serious power lives — a full exhaust system with headers and a tune can add 40–60+ HP on a 6.4L.

Best for: Maximum performance. Requires a tune and may affect emissions compliance depending on your state.

Sound Profiles: What to Expect

Different brands have distinct sound signatures:

Borla S-Type — Deep, refined, aggressive. The "gentleman's exhaust." Minimal drone on the highway.

Borla ATAK — Very loud, race-inspired. You will hear this exhaust from blocks away.

Corsa Xtreme — Aggressive under throttle but uses RSC (Reflective Sound Cancellation) technology to virtually eliminate highway drone. Best of both worlds.

Flowmaster Outlaw — Traditional American muscle car sound. Loud, aggressive, and rawer than Borla or Corsa.

AWE Touring — Refined and civilized. Great for daily drivers who want some rumble without waking the neighborhood.

The Drone Factor

"Drone" is the resonant humming/buzzing you hear inside the cabin at certain RPMs (usually 1,800–2,200 RPM on the highway). Some exhausts are engineered to eliminate it (Corsa, Borla S-Type), while others embrace it (Flowmaster Outlaw). If you daily drive your Challenger, drone tolerance should be a major factor in your decision.