Mercedes-AMG A45 W176 Downpipe — Catless, 200-Cell & 400-Cell | M133 2.0L Turbo | 2014–2018
YPG Motorsport catless downpipe for the Mercedes-AMG A45 (W176) replaces the restrictive factory catalytic converter on the M133 2.0L turbocharged four-cylinder — the most powerful series-production 2.0T engine of its generation at 381 HP. The factory cat sits directly downstream of the turbo and is the single biggest restriction in the exhaust path. Removing it unlocks faster spool, sharper throttle response, reduced exhaust gas temperatures, and a significantly more aggressive exhaust note with pronounced turbo spool noise and pops on overrun.
Power Gains with Stage 2 ECU Calibration
When paired with a YPG Stage 2 ECU calibration, the A45 delivers approximately 420–440 HP and 420–440 lb-ft of torque — a gain of +40–60 HP over stock. The M133 responds immediately to reduced backpressure and additional boost. For Stage 3+ turbo builds targeting 500+ HP, a downpipe is a mandatory prerequisite.
Catless vs 200-Cell vs 400-Cell
| Option | Flow | Sound | Best For |
|---|---|---|---|
| Catless | Maximum — zero restriction | Loudest, raw turbo bark | Track builds, maximum power |
| 200-Cell High-Flow | Very high | Aggressive, less cabin resonance | Street/track balance |
| 400-Cell GESI | High — OEM+ level | Enhanced over stock | Daily drivers, emissions compliance |
Compatibility
- 2014–2018 Mercedes-AMG A45 (W176)
- 2014–2018 Mercedes-AMG A45 S (W176)
- M133 2.0L Turbo — 360 HP (pre-facelift) / 381 HP (facelift)
Key Specifications
- Material: Low-carbon 304 stainless steel
- Construction: TIG welded, hand finished
- Flanges: CNC-machined 304 stainless — OEM mounting points
- Fitment: Direct OEM replacement — bolt-on, no fabrication
- Origin: Made in Germany
- Warranty: Lifetime
What's Included
- 1× stainless steel downpipe (catless, 200-cell, or 400-cell per selection)
- All necessary bolts, gaskets, and clamps
Installation
Professional installation recommended. 1.5–2.5 hours with lift access. Stage 2 ECU calibration required for CEL elimination and full gains. YPG offers remote ECU flashing worldwide — OBD2 tool shipped to your door, 30–45 minute guided session, fully reversible.
Related M133 Downpipes
These downpipes are the hardware prerequisite for Stage 2 power. Pair them with the matching ECU tune to extract the full gains.
View Stage 2 Tune →
