DTH | Valve exhaust system MSD & ESD (Cat-Back) | GT/GR86 & BRZ I&II | ECE approval

We offer you the DTH flap exhaust system for the Toyota GT86, Toyota GR86, and Subaru BRZ of the first and second generation. The system was specially developed for these vehicles and combines a significantly more powerful sound with intelligent, legally compliant flap control.

Thanks to ECE approval, the exhaust system is registration-free and can be legally used on public roads within the intended vehicle and approval scope.

Technical Data

• Suitable for Toyota GT86 and Subaru BRZ I
• Suitable for Toyota GR86 and Subaru BRZ II
• Pipe diameter: 63.5 mm
• Vacuum control on one side
• Dynamic, driving condition-dependent flap control
• ECE approval
• Registration-free within the approved scope of use
• Modular design
• Muffler, outlet bends, and tailpipes individually adjustable

Sound Values according to Manufacturer

GT86 and BRZ I:

• Flap closed: approx. 78 or 80 dB
• Facelift with flap open: approx. 106 dB
• Value for pre-facelift depends on the specific version

GR86 and BRZ II:

• Flap closed: approx. 78 dB
• GR86 with flap open: approx. 106 dB

The stated values are manufacturer specifications and may vary depending on vehicle condition, measurement procedure, environment, and further vehicle configuration.

Dynamic Flap Control

The legal noise limits for the GT86, GR86, and BRZ are demanding, especially for vehicles with variable exhaust system geometry. To comply with these requirements and simultaneously enable the most present sound possible outside the relevant measurement ranges, DTH has developed a driving condition and gear-dependent flap control system.

The control considers, among other things:

• engaged gear
• speed
• engine speed
• selected driving mode
• depending on the vehicle, additionally engine load

Within the legally relevant driving and ASEP measurement ranges, the flaps remain closed. Outside these areas, they can open depending on the driving mode and vehicle condition.

GT86 and BRZ I

For the GT86 and BRZ I, the flap control is influenced by the Track Mode.

In Normal Mode, the flaps remain closed in the relevant driving ranges for maximum long-distance comfort. In Track Mode, they open outside the legally prescribed noise measurement ranges, allowing for a significantly more powerful sound.

Simplified switching logic:

• Vehicle stationary: Flaps closed
  
  2. Gear in Track Mode: Flaps open
     
  3. and 4th gear between approx. 20 and 80 km/h up to 5,000 rpm: Flaps closed
• From approx. 80 km/h in Track Mode: Flaps open depending on driving condition

GR86 and BRZ II

For the GR86 and BRZ II, the control system has been further developed due to stricter noise limits.

In Track Mode, the flap can fully open in 2nd gear. In 3rd and 4th gear, it remains closed within the legally relevant measurement range. Outside this range, the system can open depending on mode, speed, and load.

Simplified switching logic:

• Vehicle stationary: Flaps closed
• 
  
  2. Gear in Normal Mode: Flaps closed
• 
  
  2. Gear in Track Mode: Flaps open
• 
  
  3. and 4th gear within the driving noise and ASEP measurement range: Flaps closed
• From approx. 80 km/h in Track Mode: Flaps open
• In Normal Mode, automatic opening possible depending on load and driving condition

This combines a subdued sound in everyday use with a significantly more emotional sound during sporty driving.

Modular Design

The DTH flap exhaust system has a modular design. Muffler, outlet bends, and tailpipes can be aligned and adjusted directly on the vehicle.

This allows for:

• Tailpipe position
• Tailpipe angle
• Distance to the bumper
• Optical alignment

to be precisely adapted to the respective vehicle.

This is particularly advantageous for vehicles with differing rear valances, diffusers, or individual modifications.

Advantages

• Legally usable flap sound
• ECE approval
• No additional registration required
• Dynamic and driving condition-dependent flap control
• Significantly more powerful sound outside the legal measurement ranges
• Pleasant driving comfort with flaps closed
• 63.5 mm pipe diameter
• Modular and individually adjustable
• Developed for GT86, GR86, and BRZ
• High-quality manufactured solution from Germany

Variant Info

You can choose different options from us; here's a brief written explanation:

Model: Gen1 and Gen2 - should be clear. The structure differs minimally due to the OPF.

TRD Kit: Here, the "standard" is that you have 2 tailpipes. With the TRD Kit (both Gen1 or Gen2), you will have 4 tailpipes if you have the corresponding rear apron installed, and for that, the system is equipped with 4* 101mm tailpipes. This, of course, costs extra.

Tailpipe variants: Here, you can select the different options for the tailpipes. Unlike other systems, DTH does NOT include a tailpipe by default, but you need one for ECE. This offers you the advantage that you can also use your own tailpipe variants; the connection is 63.5mm.

Alternatively, you can choose standard stainless steel tailpipes, flamed tailpipes, or black ceramic coating (Cerakote). Also available in custom colors, but please inquire BEFOREHAND if that is possible. For the 2-pipe systems, the diameter of the rear bezels is 114mm.

Notes

The actual flap function differs depending on the vehicle model, vehicle generation, driving mode, speed, gear, RPM, and load condition.

The ECE approval is exclusively valid for the respectively approved vehicle and system configuration. Modifications to the exhaust system, flap control, or other noise-relevant vehicle components can affect the approval and legal usability.

Installation should be carried out by a specialist workshop or a suitably experienced person. After assembly, the tailpipes and bends must be aligned stress-free, and all connections checked for tight fit and sealing.

Sound video Gen1 GT86/BRZ I

Sound video GR86/BRZ II (Stock vs DTH Flap)