VRP H-13 Head Studs (M157/278)

VRP H-13 Head Studs — Mercedes-AMG M157 5.5L Twin Turbo V8 / Mercedes M278 4.7L Twin Turbo V8

The Ultimate Solution to Factory Head Bolt Failure

The M157 and M278 twin turbo engines are notorious for ripping the threads out of the block. The factory head bolts are installed as “torque to yield,” meaning they permanently stretch when tightened. This stretching compromises clamping force over time, and under the elevated cylinder pressures of a tuned engine, the heads lift off the gasket surface — mixing oil, coolant, and combustion gases. Once the head lifts, you’re looking at gasket failure and catastrophic internal damage.

To address this, we developed the VRP H-13 Head Studs. Our head studs are a direct replacement for the problematic factory bolts. Unlike most aftermarket head studs made of mild steel, our VRP H-13 Head Studs are crafted from premium H-13 steel. This material is renowned for its strength and hardness, making our head studs the toughest on the market. Studs load in pure tension rather than the torsion generated by factory bolts, delivering more consistent and uniform clamping force across the entire head gasket surface — keeping the heads down where they belong, even at extreme boost levels.

Upgrades the following OEM part numbers:

• 278016016964KT1
• 278016016964KT

Key Features:

• Superior Strength: Made from H-13 steel, offering unmatched durability under extreme cylinder pressures.
• Prevents Head Lift: Maintains consistent clamping force to keep the cylinder heads sealed to the block.
• Thread Protection: Stud design eliminates the torsional loading that causes the factory thread pull-out issue.
• Direct Replacement: Fits perfectly in place of factory head bolts with no block modifications required.
• Enhanced Engine Protection: Keeps oil, coolant, and air charges properly separated, avoiding catastrophic internal damage.

Kit Contents:

• 20x VRP H-13 Head Studs
• 20x Washers
• 20x Nuts

Fitment — M157 5.5L Twin Turbo V8:

• Mercedes-Benz E63 AMG — M157 5.5L Twin Turbo (2011–2017)
• Mercedes-Benz CLS63 AMG — M157 5.5L Twin Turbo (2011–2018)
• Mercedes-Benz SL63 AMG — M157 5.5L Twin Turbo (2012–2019)
• Mercedes-Benz S63 AMG — M157 5.5L Twin Turbo (2011–2017)
• Mercedes-Benz CL63 AMG — M157 5.5L Twin Turbo (2011–2014)
• Mercedes-Benz ML63 AMG — M157 5.5L Twin Turbo (2012–2015)
• Mercedes-Benz GL63 AMG — M157 5.5L Twin Turbo (2012–2015)
• Mercedes-Benz GLE63 AMG — M157 5.5L Twin Turbo (2016–2019)
• Mercedes-Benz GLS63 AMG — M157 5.5L Twin Turbo (2015–2019)
• Mercedes-Benz G63 AMG — M157 5.5L Twin Turbo (2012–2018)
• Mercedes-Benz G63 AMG 6×6 — M157 5.5L Twin Turbo (2014)

Fitment — M278 4.7L Twin Turbo V8:

• Mercedes-Benz E550 — M278 4.7L Twin Turbo (W212, 2012–2016)
• Mercedes-Benz CLS550 — M278 4.7L Twin Turbo (W218, 2012–2018)
• Mercedes-Benz S550 — M278 4.7L Twin Turbo (W221/W222, 2011–2017)
• Mercedes-Benz SL550 — M278 4.7L Twin Turbo (R231, 2013–2018)
• Mercedes-Benz CL550 — M278 4.7L Twin Turbo (C216, 2011–2014)
• Mercedes-Benz GL450 — M278 4.7L Twin Turbo (X166, 2013–2016)
• Mercedes-Benz GL550 — M278 4.7L Twin Turbo (X166, 2013–2016)
• Mercedes-Benz GLE550 — M278 4.7L Twin Turbo (W166, 2016–2018)
• Mercedes-Benz GLS550 — M278 4.7L Twin Turbo (X166, 2017–2019)
• Mercedes-Benz ML550 — M278 4.7L Twin Turbo (W166, 2012–2015)
• Mercedes-Benz G550 — M278 4.7L Twin Turbo (W463, 2015–2018)

Upgrade to VRP H-13 Head Studs and safeguard your M157 or M278 against head lift and thread pull-out — the two most common and costly failure points on these platforms. Enjoy peace of mind with our high-strength solution, designed to outlast and outperform the stock components.

Step-by-Step Instructions for Installation and Removal

Installation Instructions

1. Prepare the Components:
   • Apply a small amount of silicone to the washer and nut. This helps seal against the head and bolt since it’s a two-piece design.
2. Torque Sequence:
   • Follow the sequence diagram provided to ensure even torque distribution.
   • Tighten the bolts in the following stages:
     • Step 1: Torque each bolt to 55 Nm
     • Step 2: Increase torque to 110 Nm
     • Step 3: Finalize torque at 150 Nm
3. Sequence Options:
   • One Bolt at a Time: Complete all three torque stages (55 Nm → 110 Nm → 150 Nm) on one bolt before moving to the next.
   • All Bolts Simultaneously: Tighten all bolts to 55 Nm first, then proceed to 110 Nm, and finally to 150 Nm, following the sequence at each stage.