HKS BCD PISTON AND CONROD KIT G16E HC-TT S3 FOR TOYOTA GR YARIS TOYOTA GR COROLLA G16E-GTS 21004-AT011

 

HKS BCD PISTON AND CONROD KIT G16E HC-TT S3 FOR TOYOTA GR YARIS TOYOTA GR COROLLA G16E-GTS 21004-AT011

The HKS BCD Piston & Conrod Kit G16E HC-TT S3 (Part No. 21004-AT011) is a high-compression forged piston and connecting rod kit.

It was designed for the Toyota G16E-GTS 1.6L turbo 3-cylinder engine used in the Toyota GR Yaris and GR Corolla. It is part of HKS STEP3 engine internal upgrades aimed at higher power builds. 

Key Specifications

• Engine: Toyota G16E-GTS
• Compatible cars: Toyota GR Yaris / GR Corolla
• Bore: 87.5 mm
• Stroke: 89.7 mm
• Displacement: 1,618 cc
• Piston weight: ~352 g
• Piston pin: 24 mm
• Compression ratio: ~10.6–10.7 (depending on gasket thickness)  

Main Technologies & Engineering

1. BCD (Bridge Concept Design) Forged Pistons

• Made from A2618 forged aluminum, a material commonly used in high-temperature racing pistons.
• Bridge structure improves rigidity while keeping the piston lightweight.
• Two-layer anti-seizure coating reduces friction and improves durability.  

2. HC-TT “Triple Tumble” Crown Design

• HKS developed a Triple Tumble piston crown.
• Creates an extra airflow tumble effect inside the cylinder during compression.
• Improves flame propagation and knock resistance.  

This allows:

• Higher compression
• Better combustion efficiency
• Increased power potential.

3. Reinforced Billet Connecting Rods

• Nickel-chrome alloy steel I-beam rods.
• About 25% stronger than factory rods.
• WPC surface treatment improves fatigue strength and durability.  

4. Advanced Cooling & Wear Protection

• Designed to work with three oil jets for piston cooling.
• Nickel plating above the top ring groove increases wear and knock resistance.
• Titanium coating on the top ring improves durability under high boost.  

Performance Advantages

This kit is typically used for high-power GR Yaris / GR Corolla builds:

• Higher compression for improved response and power
• Much stronger bottom-end reliability
• Reduced piston weight for faster engine revving
• Improved detonation resistance under high boost

In many builds this type of bottom end is used for 450–600+ hp engine setups depending on turbo, fueling and tuning.

What Comes in the Kit

• Forged BCD pistons
• Billet I-beam connecting rods
• Piston pins
• Required hardware for assembly.  

✅ Typical upgrade pairing

• HKS forged crankshaft or balanced stock crank
• ARP head studs
• Upgraded head gasket
• Larger turbo (G25-660 / T51R / EFR etc.)

HKS BCD PISTON AND CONROD KIT G16E HC-TT S3 FOR TOYOTA GR YARIS TOYOTA GR COROLLA G16E-GTS 21004-AT011

HKS METAL CATALYZER FOR TOYOTA GR YARIS GXPA16 33005-AT011

 

HKS METAL CATALYZER FOR TOYOTA GR YARIS GXPA16 33005-AT011

The HKS Metal Catalyzer (33005-AT011) is a high-flow sports catalytic converter and front pipe designed for the Toyota GR Yaris GXPA16 with the G16E-GTS 1.6L turbo engine. 

It replaces the factory catalytic converter to improve exhaust flow while still maintaining emissions purification. 

Key Features

• High-flow metal catalyst core (150 cell)
  Replaces the restrictive OEM ceramic catalyst (600/300 cell density), greatly reducing exhaust backpressure.  
• Dual metal catalyst design
  Both primary and secondary cats use 150-cell metal cores for better flow and durability.  
• Larger pipe diameter
  Enlarged from 70 mm (stock) to ~75 mm for higher exhaust volume and faster turbo response.  
• Performance gain
  With stock muffler, power increases about +10.6 PS and +19.5 Nm.  
• Heat-shield compatible
  Designed so the OEM heat shield can still be installed.  
• Premium build quality
  Fully TIG-welded and buff-polished stainless construction.  

Technical Comparison (Stock vs HKS)

Specification	Stock GR Yaris	HKS Metal Catalyzer
1st Catalyst Cell Density	600 cpsi	150 cpsi
2nd Catalyst Cell Density	300 cpsi	150 cpsi
Max Pipe Diameter	70 mm	~74.7- 75 mm
Idle Sound	59 dB	59 dB
Rev Sound	79 dB	80 dB

Meaning:

• Much less restriction for turbo spool
• Slightly louder and deeper exhaust note
• Improved mid-range torque and top-end power

Fitment

• Vehicle: Toyota GR Yaris (GXPA16)
• Engine: G16E-GTS 1.6L 3-cyl turbo
• Model years: 2020–March 2024 (not compatible with newer post-2024 revision models).  

✅ Best used with:

• HKS Super Turbo Muffler
• HKS Legamax Premium exhaust
• ECU tune or intake upgrade

Together these mods unlock significantly more performance from the GR Yaris turbo system.

HKS METAL CATALYZER FOR TOYOTA GR YARIS GXPA16 33005-AT011

 

BMW G8X M3/M4 Carbon Fiber Front Hood

DESCRIPTION

• Elevate your BMW G8X M3/M4 with Bimmer Plug’s Carbon Fiber Front Hood, designed to combine aggressive styling with lightweight performance for the ultimate M experience.
• Crafted from premium-grade carbon fiber, this hood reduces weight, enhances airflow, and amplifies aerodynamics, optimizing both aesthetics and functionality.
• Engineered for a precise OEM+ fit, it seamlessly integrates with the sleek lines of your M3/M4, delivering a race-inspired presence on the road.

BMW G8X M3/M4 Carbon Fiber Front Hood

Titanium vs Inconel Exhaust on Ferrari & Lamborghini

 

Titanium vs Inconel Exhaust on Ferrari & Lamborghini

Sound, Weight & Performance Comparison

High-performance exhaust systems for supercars such as Ferrari and Lamborghini often use titanium or Inconel because these materials provide superior strength, heat resistance, and weight savings compared with conventional stainless steel.

Manufacturers like Akrapovic, Kline Innovation, IPE (Innotech Performance Exhaust), and Armytrix use these materials in their premium exhaust systems.

Understanding the differences between titanium and Inconel exhaust systems helps determine which is best for a street supercar or a race-focused build.

1. Titanium Exhaust Systems

Titanium exhausts are widely used in aftermarket systems for modern supercars because they offer an exceptional strength-to-weight ratio.

Key Characteristics

• Around 40–45% lighter than steel exhaust systems
• Excellent corrosion resistance
• Strong and durable
• Handles temperatures up to ~800°C

Typical Brands Using Titanium

1. Akrapovic

2. IPE (Innotech Performance Exhaust)

3. Armytrix

Sound Profile

Titanium exhaust systems typically produce:

• A clean, exotic supercar tone
• Higher-frequency sound than stainless steel
• Crisp high-RPM scream

On a Ferrari 458 Italia, titanium systems emphasize the engine’s naturally aspirated character, especially near the 9,000-rpm redline.

Best for:

Street supercars and lightweight performance builds.

2. Inconel Exhaust Systems

Inconel is a nickel-chromium superalloy originally developed for aerospace and racing applications.

It is widely used in motorsport exhaust systems, including Formula racing cars.

Key Characteristics

• Can tolerate 1000°C+ temperatures
• Extremely resistant to heat fatigue
• Stronger under extreme thermal stress
• Ideal for high-performance engines

Typical Brands Using Inconel

1. Kline Innovation

2. Some racing systems from Akrapovic

Sound Profile

Inconel exhaust systems are known for:

• Sharper and higher-pitched tone
• Raw race-car sound
• Very aggressive high-RPM note

On a Lamborgini Huracan, an Inconel exhaust can produce an extremely F1-style scream, especially when paired with high-flow headers.

Best for:

Track cars and motorsport-focused supercar builds.

Titanium vs Inconel Exhaust Comparison

Feature	Titanium Exhaust	Inconel Exhaust
Weight	Extremely light	Slightly heavier
Heat Resistance	Up to ~800°C	1000°C+
Sound	Clean exotic tone	High-pitch race sound
Durability	Excellent	Best under extreme heat
Cost	Expensive	Very expensive
Motorsport Use	Track cars	Formula-level racing

Ferrari vs Lamborghini Exhaust Preference

**Ferrari

Models like the Ferrari 458 Italia often use titanium exhaust systems because they enhance the naturally aspirated V8 sound while reducing weight.

Popular exhaust brands include:

• Akrapovič
• Capristo

**Lamborghini

Cars such as the Lamborghini Huracan or Lamborghini Aventador often benefit from Inconel systems because of the higher exhaust temperatures and aggressive track-oriented driving.

Popular systems include:

• Kline Innovation
• Armytrix

Final Verdict

Titanium Exhaust

• Best for lightweight street supercars
• Balanced exotic sound
• Lower weight improves handling

Inconel Exhaust

• Best for extreme performance and racing
• Higher heat tolerance
• Raw motorsport sound