GSC Power Division 2157-8 Super Alloy +1mm Exhaust Valve Set/8 Coyote Gen 1/2

Vehicle Fitment

• 2011-2014 Ford Mustang GT, 5.0L Coyote V8, Gen 1
• 2015-2017 Ford Mustang GT, 5.0L Coyote V8, Gen 2

Fitment Notes

• +1mm oversized head diameter (32.75mm vs. 31.75mm OEM/standard) - requires valve seat machining to match the enlarged head diameter before installation
• 45° valve seat contact angle - differs from the OEM 40° design; a valve job must be performed to machine the seat to 45° for proper sealing and valvetrain geometry
• Compatible with OEM-style keeper/lock systems - GSC recommends against reusing existing valve locks on performance applications due to potential material grooving from prior wear
• Set of 8 covers one full bank of exhaust valves (one cylinder head) on the Coyote - two sets required for a complete dual-head engine build
• For Gen 1/Gen 2 Coyote only - Gen 3 (2018-2023) and Gen 4 (2024+) Coyote use a different valve specification; see separate Gen 3/4 listings

Features

• Super Alloy construction - engineered for extreme exhaust gas temperature (EGT) resistance, outperforming standard stainless steel in high-horsepower, forced induction, or high-heat applications
• +1mm oversized head (32.75mm) - provides additional valve seat material for head rebuilds involving seat cutting, or for maximizing flow area where the head has been machined
• Back cut valve head design - reduces valve weight for higher RPM capability and improves airflow at the seat without increasing spring seat pressure requirements
• Micro-polished valve stem - minimizes oil retention on the stem, reducing drag and wear within the valve guide for smoother operation and better oil control
• Hardened or stellite-fused valve tip - maintains within 5 Rockwell C of the rocker/tappet hardness for extended tip life and reduced valvetrain wear
• Keeper groove precisely adjusted to balance intake and exhaust spring pressures - reduces the need for valve spring shims when used with GSC spring kits
• Valve tip lengths optimized for the Coyote Gen 1/2 application - minimizes tipping, maintains proper valvetrain geometry, and simplifies valve lash setup
• Designed using advanced 3D engineering and flow simulation software with real-world flow testing on the specific application

Specifications

• Part Number: 2157-8
• Type: Super Alloy Exhaust Valve - +1mm Oversized Head
• Head Diameter: 32.75mm (+1mm over OEM 31.75mm)
• Valve Seat Angle: 45° (OEM is 40° - valve job required)
• Material: Super Alloy (high EGT resistance)
• Quantity: 8 (one cylinder head / one bank of exhaust valves)
• Application: Ford 5.0L Coyote Gen 1 (2011-2014) and Gen 2 (2015-2017)

Included Components

• 8x GSC Power Division Super Alloy Exhaust Valves - 32.75mm head, +1mm oversized
• Note: Valve springs, retainers, valve stem seals, and valve guides sold separately; valve seat machining required

Product Description

The GSC Power Division 2157-8 is a set of 8 Super Alloy exhaust valves for the Ford 5.0L Coyote Gen 1 and Gen 2 (2011-2017 Mustang GT), featuring a 32.75mm head diameter - 1mm larger than the OEM 31.75mm standard. The oversized head is used in head builds where valve seats have been cut or machined, providing the additional material needed for a proper seating surface after seat work is performed. Super Alloy material offers exceptional exhaust gas temperature resistance compared to conventional stainless steel, making this the appropriate choice for high-output naturally aspirated, supercharged, or turbocharged Coyote builds where EGTs are elevated.

GSC's exhaust valves for the Coyote feature a 45° seat contact angle, which differs from the OEM 40° design - a valve job to machine the seat to 45° is required for correct sealing and valvetrain geometry. The micro-polished stem, back cut head, stellite-fused tip, and precisely adjusted keeper groove are all standard across GSC's valve line, ensuring improved flow, extended service life, and compatibility with GSC's spring and retainer kits. This set covers one cylinder head; two sets are required for a complete Coyote engine build.