HKS Dual Muffler Catback Exhaust without OPF - 2020+ A90 Supra

Dual Exit Cat-Back Exhaust Without OPF for the 2020+ GR Supra

The HKS Dual Muffler Cat-Back Exhaust for the 2020+ Toyota GR Supra is a full cat-back system with dual exit tips, designed for use on vehicles without the OPF (Otto Particulate Filter). This distinction matters. The A90 Supra was sold in OPF and non-OPF variants depending on market and model year, and an exhaust system designed for one does not always fit the other correctly. Verify your car's OPF status before ordering. The dual exit layout gives the rear bumper a symmetrical, purposeful appearance and the dual muffler design allows HKS to tune the exhaust note for character without excessive drone.

Specs & Highlights

• Dual muffler cat-back system
• Dual exit tip configuration
• For non-OPF A90 Supra variants
• Stainless steel construction
• Tuned exhaust note, character without drone
• Fitment: 2020+ Toyota GR Supra (non-OPF variants)

60.5mm Pipe, Dual 115mm Tips, and Sound Level

The KT001 uses 60.5mm (2.375 inch) diameter main pipe throughout, connecting to dual 115mm (4.5 inch) round tips. Total system weight is approximately 12.4 kg. Sound level is rated at approximately 96 dB(A) at 1m at WOT. The dual muffler configuration uses two independent resonator chambers for each tip, which is why the sound is more controlled than a straight dual-tip pipe, each side has its own tuned resonance rather than sharing one muffler body.

Dual Muffler Design and Daily Usability

The dual exit configuration is a visual statement as much as an engineering choice. The symmetric rear bumper appearance with matched tips frames the lower rear of the Supra correctly and gives it the presence that a single exit setup does not. The muffler design is HKS's: not a straight-pipe or resonator-delete approach, which means the sound level is elevated but livable for daily use.

OPF vs Non-OPF: Verify Before Ordering

The non-OPF designation is important for ordering. Some markets received A90 Supras with a particulate filter in the exhaust path; this exhaust is engineered for the non-OPF configuration. If you have an OPF-equipped car, the system will not fit correctly. Check your vehicle's documentation or consult with a dealer to confirm.

The FT Breakdown

The HKS Dual Muffler is for Supra owners who want the visual and auditory upgrade without moving to the most aggressive options in the market. It is a complete, daily-drivable exhaust system that makes the right sounds at the right times and looks correct on the car. For a platform this visually intentional, the exhaust tip configuration matters. At 12.4 kg with dual 115mm tips, the KT001 is approximately 3 kg lighter than a comparable quality dual-exit cat-back from a conventional manufacturer — HKS keeps weight down with proper mandrel bending and good wall thickness specification rather than making cheap tradeoffs in the pipe material. The OPF verification requirement is real: ordering the wrong version is a fitment problem that costs time and shipping.