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BenzUnited Parts

M278 Intake Spacer Kit + aFe Magnum FLOW Pro 5R Filters (E550 / CLS550 / S550)

M278 Intake Spacer Kit + aFe Magnum FLOW Pro 5R Filters (E550 / CLS550 / S550)

Regular price $325.00 USD
Regular price Sale price $325.00 USD
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The smartest OEM+ upgrade for every tuned E550 / CLS550 / S550 / GL550 on the M278 4.7L BiTurbo

Fix the hidden airbox restriction your headers, tune, and downpipes are already begging for.


Why This Magnum FLOW OE Combo Actually Works on the M278

✅ Airbox Spacer (Left + Right)
Raises the filter sealing plane → smoother, higher-volume airflow into the MAF housing.
✅ aFe Magnum FLOW OE Replacement Air Filter w/ Pro 5R Media
Maximum-flow oiled cotton gauze (noticeably more airflow than Pro Dry S), reusable, perfect MAF compatibility.
✅ Factory Airbox Stays 100% Stock
Keeps perfect cold-air routing and heat shields — no heat-soak like open intakes.

Real-World Results Owners Report

  • Even crisper throttle tip-in and stronger mid-range pull
  • Maximum power consistency on hot days and repeated pulls
  • Extra headroom for your existing tune, downpipes, and E85
  • Zero check-engine lights • No ECU retune required

“Swapped to the Magnum FLOW OE w/ Pro 5R combo and the car feels a full step quicker. Throttle is razor sharp with the downpipes.” – Alex R., 2015 CLS550 • 512 whp

What You Get

  • ✔ 2× Precision CNC-machined airbox spacers (left + right)
  • ✔ 2× aFe Magnum FLOW OE Replacement Air Filters w/ Pro 5R Media
  • ✔ All stainless hardware + install instructions

Fits These M278 4.7L BiTurbo Models

Model Chassis Years
E 550 • CLS 550 W212 / C218 2012–2016
S 550 / S 560 W222 • W221 2014–2017 (W222) / 2012–2013 (W221)
GL / GLS 450 • 550 X166 2013–2019
ML 450 • ML 550 W166 2012–2015

Install in ~20 minutes • No tools beyond a 10mm socket • Fully reversible

🔥 Add to Cart – Ships Same Day

BenzUnited Parts • Mercedes Performance Specialist

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