HKS Metal Head Gasket (NA Vehicles) - 2013-2021 Scion FR-S / Subaru BRZ / Toyota 86

Metal Head Gasket for Naturally Aspirated FA20 Applications

The HKS Metal Head Gasket for naturally aspirated 2013-2021 FR-S, BRZ, and 86 applications is the appropriate head gasket choice for high-revving NA builds where the OEM gasket may be a long-term reliability concern, or as a preventive replacement in high-mileage FA20 engines. While the naturally aspirated FA20 does not generate the cylinder pressure of a boosted application, high-rpm NA builds. Particularly those with performance camshafts, high-compression pistons, or significant head work, benefit from the improved sealing properties of the HKS metal construction.

Specs & Highlights

• Metal head gasket construction
• For naturally aspirated FA20 applications
• Improved sealing over OEM multi-layer steel
• Appropriate for high-rpm NA builds and performance engine rebuilds
• Standard thickness for NA applications
• Fitment: 2013-2021 Scion FR-S / Subaru BRZ / Toyota 86

t=1.2mm Standard, 20-25% Clamping Force Improvement

The HKS metal head gasket for naturally aspirated FA20 applications is the t=1.2mm standard thickness, matching the OEM gasket thickness to avoid compression ratio change. The stainless fire ring construction provides a measured combustion seal clamping force improvement of approximately 20–25% over the OEM multi-layer steel design at equivalent head bolt torque. ARP2000 or ARP Custom Age 625+ head studs are the recommended complement, providing the consistent torque retention the metal gasket's clamping requirement depends on.

When NA Builds Need a Better Head Gasket

Naturally aspirated head gasket failure is less common than forced induction failure but it happens. Particularly in high-mileage engines, engines that have experienced overheating, or engines with significant valve and head work that changed the sealing surface geometry. The HKS metal gasket provides a reliable sealing solution in these cases.

ARP Head Studs Complete the Head Sealing Upgrade

Installation requires head removal. If you are already doing significant engine work on the FA20. Camshaft installation, head port work, piston replacement, the head gasket replacement adds minimal additional labor and significantly improves long-term reliability. Combine with ARP head studs for the complete head sealing upgrade.

The FT Breakdown

The NA head gasket is for engine builders and high-mileage FA20 owners doing a proper refresh. It is not a performance part in the conventional sense. It is a quality part that keeps your engine together. The HKS metal construction is a straightforward upgrade from the OEM gasket design. The 20–25% clamping force improvement over the OEM MLS gasket at equivalent torque is the quantified reason to install this gasket on any high-revving NA FA20 build. Combined with ARP head studs — which provide more consistent torque retention across thermal cycles than the factory bolts — the head sealing system becomes genuinely bulletproof rather than a potential failure point in a high-RPM application.