The long-awaited Gen2 compatible muffler is here!
Pursuing sound, performance, and appearance, bringing out the sports car aesthetic!

 

 

■Features

• Aiming to achieve both low exhaust pressure and quietness. We have used the knowledge we have cultivated through the product development of the previous gen GR Yaris and GR Corolla!
• We have suppressed the unpleasant muffled noise at normal RPMs while emphasizing a powerful, sporty sound at throttle. We believe the sound quality which makes driving more enjoyable.
• The optimized pipe layout and straight structure inside the silencer achieves extremely low exhaust pressure.
• HKS rubber stays and a special bracket are included to reduce lateral movements of the muffler during sporty driving.

 

 

 

 

 

 

Remarks

Compatible with AT and MT. Not compatible with vehicles with 17-inch wheels or rear constant speed differentials. Cannot be installed on Gen 1 vehicles

 

 

 

---

 

●Performance comparison

 

 

• The maximum values ​​for both power and torque exceeded the stock system
• When measuring the power output, we also measured the exhaust pressure (*). As the engine speed increased, the difference became larger, confirming a significant reduction in exhaust pressure.
• With improved exhaust efficiency, making a muffler that will show its true value in further tuning!!

 

Power/ Torque maximum value

 

Notes regarding the notations in the graph and table:
STM: Super Turbo Muffler 31029-AT017 (used for testing)

• Exhaust pressure is measured between the spherical flange and the middle silencer.
• Since the stock ECU uses torque-based output management, simply replacing the muffler will give the same output as the stock product.
• Graphs and figures are the results of in-house testing. They may vary depending on the vehicle and measuring equipment.

 

Test Vehicle: GR Yaris 4BA-GXPA16
Vehicle Specs: Super Turbo Muffler　31029-AT017
(All other parts were stock)

 

 

●Appearance & Layout Comparison

31029-AT017

The knowledge cultivated through the development of the previous gen GR Yaris and GR Corolla has been fully utilized!

 

• This product was developed based on data accumulated from the development of the earlier gen GR Yaris and GR Corolla, and the optimal layout, including silencer configuration and pipe length, was derived.
• It controls unpleasant low tones and reduces muffled noise inside the car at normal RPMs, while producing a sporty sound making it clear that you have changed the muffler!
• The rich low tones have a strong feel, and the sound quality matches the powerful feeling of the GR Yaris.
• It has a two-part configuration of an intermediate and a main muffler.

 

GR Yaris Stock Muffler

 

• Immediately after the flange the pipe is becomes 70mm
• After the intermediate silencer, it becomes 65mm.
• The silencer is designed to distribute the exhaust to the left and right.
• One piece structure with no divisions.

 

 

●Appearance comparison

• We pay attention not only to performance but also to the visual details.
• The main muffler is TIG welded and carefully finished by our skilled craftsmen one by one.
• The products produced using our outstanding technology are finished with both strength and beauty.

 

 

31029-AT017 Super Turbo Muffler

 

 

 

About HKS muffler

*1: About center pipe
Diameter of center pipe is the portion that has the largest diameter. (Excluding silencer and tip.) It is the condition with stock suspension.

*2: Minimum road clearance between HKS muffler (Any parts included in the kit) and road surface. Therefore, it may be different from actual road clearance of the vehicle.
The data is basically the condition with stock suspension. However, please understand that some items have data with low down spring or ride height adjustable suspension kit.

Caution: Hook, bracket, stay may be changed without prior notice.

★ Exhaust noise level at idle.