The factory exhaust manifold for the Scion FR-S & Subaru BRZ was designed in the 4-2-1 type layout for a better performance and torque at lower engine speeds. Because the first catalytic converter is mounted at the exhaust manifold, exhaust pulsatory motion makes the exhaust gas flow back to the pipe in the middle RPM range which could cause a loss of power output by behaving as an exhaust gas recirculation.
The HKS exhaust manifold follows the same 4-2-1 type layout, but by creating it without the catalytic converter, the HKS manifold provides both more torque in the middle RPM range and more peak power at high RPM's. Street driveability is increased with the bump in torque, and at high RPM it provides more power and enhances the clean feel of the high RPM driving characteristics.
- HP Gains: +10 hp
- TQ Gains: N/A
- SUS304 Stainless Steel construction
- Retains OEM 4-2-1 Layout
- Eliminates OEM Catalytic Converter
- Adds mid-range torque, more peak power
- Subaru BRZ (All Models) 2.0L 13+
- Scion FR-S (All Models) 2.0L 13+
- Toyota GT-86 (All Models) 2.0L 13+