M156 CNC-Ported Heads — Flow-Matched Cylinder Heads for 6.2L AMG V8
The factory M156 cylinder heads flow well from the factory — but "well" is not "race-ready." Our M156 CNC-ported heads are flow-bench developed, precision-machined, and assembled with upgraded valvetrain to unlock the airflow your forged bottom end needs. Built in-house at YPG Motorsport in Kuwait, sold as a pair, and shipped worldwide.
What Are CNC-Ported Heads?
CNC porting uses computer-controlled machining to reshape the intake and exhaust ports inside your cylinder heads. Every port is cut to our proven flow-bench program — identical runner volumes, matched flow rates across all eight cylinders. The result is more air in, more exhaust out, and a broader, stronger powerband from idle to redline.
Our ported heads are not just opened up with a die grinder. They are CNC-machined to micron-level precision, then flow-tested to verify each head meets our target CFM numbers.
M156 Ported Heads Specifications
| Parameter | Specification |
|---|---|
| Head type | M156 DOHC 4-valve per cylinder |
| Porting method | 5-axis CNC, flow-bench validated |
| Intake valves | Upgraded stainless steel, oversized |
| Exhaust valves | Upgraded Inconel, oversized |
| Valve springs | Uprated, matched spring pressure |
| Retainers | Titanium |
| Sold as | Pair (left + right head, assembled) |
| Application | Race / off-road use |
| Build time | 7–21 days |
| Shipping | FedEx / DHL worldwide to door |
Why Port the M156 Heads?
On a naturally aspirated engine, airflow is everything. Ported heads directly increase volumetric efficiency — more air per combustion cycle means more power. On a boosted M156 (supercharged or turbocharged), ported heads reduce pumping losses and let the engine breathe more efficiently at high boost pressures, which means more power and lower intake temps.
If you have already built or are building an M156 forged short block, ported heads are the natural next step. Together, they form a complete M156 crate engine.
Upgraded Valvetrain
Our M156 ported heads come fully assembled with an upgraded valvetrain. Intake and exhaust valves are oversized and machined from premium alloys — stainless steel intake, Inconel exhaust — for durability at sustained high RPM and high heat. Springs are matched to our cam profiles with consistent seat and open pressures across all 32 valves. Titanium retainers reduce valvetrain mass for faster response and higher safe RPM.
Pairing with Your Build
Our M156 ported heads bolt directly onto any M156 block. Pair them with:
- M156 Forged Short Block — add our ported heads to your new bottom end.
- Your existing M156 block — if your bottom end is healthy, ported heads alone can transform the engine.
- M156 Crate Engine — ported heads are already included in our complete long block builds.
Read more: Short Block vs Long Block vs Crate Engine — What's the Difference?
How to Order
Contact us at sales@ypgmotorsport.com with your engine details. Our M156 ported heads are quoted per build based on your valvetrain and porting spec. We ship worldwide via FedEx or DHL.
Browse all AMG Engine Builds or jump to the full M156 Engine Builds collection.
Frequently Asked Questions
What is included with the M156 ported heads?
You receive a pair of fully assembled cylinder heads — CNC-ported, with upgraded intake and exhaust valves, uprated springs, titanium retainers, and new valve seals. Ready to bolt on.
Will ported heads fit my stock M156 engine?
Yes. Our ported heads use the OEM bolt pattern and gasket surfaces. They are a direct bolt-on replacement for factory M156 heads.
Do ported heads require a tune?
We strongly recommend an ECU recalibration to take full advantage of the increased airflow. YPG Motorsport offers ECU tuning for all M156-equipped vehicles.
What vehicles use the M156 engine?
The M156 6.2L V8 powers the Mercedes-AMG C63 (W204), SLS AMG, CLK63 AMG, and C63 Black Series.
Can I order ported heads and a short block together?
Yes — or you can order the complete M156 crate engine, which includes both. Contact us for pricing.