Downpipe Exhaust/Test Pipes for 2008-2018 Nissan 370z Infiniti G37 Z34

Flashark Test Pipes Downpipe for G37 and 370Z VQ37VHR Builds

A freer-flowing front exhaust section can make the VQ37 feel sharper, louder, and more responsive without turning the whole build into a custom-fabricated exhaust project. This Flashark stainless test pipe kit is built for 2008-2013 Infiniti G37, G37x, and 2009-2018 Nissan 370Z 3.7L VQ37VHR models, replacing the restrictive factory catalytic converters with 2.5-inch catless pipes for off-road and track use.

Many owners search this upgrade as G37 downpipes, 370Z downpipes, G37 test pipes, or 370Z test pipes. On the naturally aspirated VQ37 platform, the most accurate name is catless test pipes because this kit replaces the factory catalytic converter section rather than a turbo downpipe. The result is better exhaust flow, a more aggressive VQ tone, and stronger performance potential when paired with the right supporting parts.

Specifications

This kit is built as a pair of catless stainless steel test pipes. On the VQ37VHR platform, many owners call this section “downpipes,” but the part’s main job is replacing the factory catalytic converter pipes after the exhaust manifolds.

Package Included:

We provide everything you need for a 100% bolt-on experience. No extra trips to the hardware store required.

• 2x Performance Downpipes: High-flow stainless steel with pre-welded O2 sensor bungs.

• 4x High-Temp Flange Gaskets:

  • 2x Heavy-duty 3-bolt gaskets.

  • 2x Precision-fit 2-bolt gaskets.

• 10x Pieces of Professional Hardware:

  

  
  (You will get exactly as shown in the picture above)

Features & Performance Gains:

Unlike standard OEM replacements, our test pipes 370Z and G37 kits are engineered to outperform the competition:

• Maximize Engine Output: Free up trapped horsepower and gain significant low-end torque.
• Unrestricted Flow Design: Large 2.50" diameter, free-flow tubing makes the exhaust airflow incredibly smooth, specifically designed for high-performance track racing.
• Superior Construction: Crafted from high-quality 16-gauge T-304 stainless steel utilizing computerized mandrel-bends to prevent exhaust turbulence.
• TIG Welded Joints: All joints are professionally TIG welded for maximum strength, preventing cracking under extreme heat and vibration.
• CNC Machined Flanges: Thick, CNC-machined flanges provide maximum durability and a perfectly flat mounting surface to prevent leaks. Chrome-plated for corrosion resistance.

What This Test Pipe Kit Does

The factory catalytic converters help control emissions, but they also create restriction in the front exhaust section. Replacing them with catless test pipes gives exhaust gases a more direct path out of the engine, which can improve throttle response, increase exhaust volume, and support stronger power gains when the rest of the setup is matched well.

Performance Gain You Can Expect

On a mostly stock G37 or 370Z, a realistic gain from catless test pipes is usually around 8-15 HP. With a freer-flowing Y-pipe or cat-back exhaust and a proper ECU tune, the front exhaust upgrade can support about 10-20 HP depending on the car, fuel, tune quality, and supporting modifications.

The biggest change is not always peak horsepower. Many owners notice quicker revving, stronger mid-range response, and a much more open exhaust tone. A tune is not always required just to physically drive the car, but it is recommended if you want cleaner fueling, better drivability, and fewer CEL-related issues on an off-road setup.

Sound, Rasp, and Daily Driving Feel

These are non-resonated catless test pipes, so they will make the car louder than stock catalytic converters. With a factory-style or moderate cat-back, the tone is usually sharper and more aggressive. With a single-exit exhaust, muffler delete, or very open Y-pipe, expect more rasp, smell, and possible drone around cruising RPM.

Flashark's All-in-One Kits & Recommended Upgrades

Often, after purchasing the 2008-2018 Nissan 370z Infiniti G37 Z34 Downpipe Exhaust, customers will also purchase other items. Come on, check out Flashark's all-in-one kits and modify your car to your heart's content!

Complete Your Build: Maximize your exhaust flow and complete your system upgrade by pairing these downpipes with our 3-Inch Single Tip Cat-Back Exhaust for 2009-2020 Nissan 370Z.

Test Pipes vs Factory Catalytic Converters

Factory catalytic converters are built for emissions control and quieter operation. Flashark catless test pipes are built for off-road exhaust flow and a more aggressive sound. The right choice depends on how you use the car and whether your build must meet local emissions requirements.

• Factory catalytic converters: Quieter, emissions-focused, and better for street compliance, but more restrictive when you are building an off-road performance exhaust setup.
• Flashark catless test pipes: Freer-flowing 2.5-inch stainless pipes that replace the factory catalytic converters for off-road and track use. They deliver a louder tone, stronger exhaust flow, and a sharper VQ sound.

Tuned vs Untuned Setup

These catless test pipes can be installed on a compatible G37 or 370Z without an immediate tune, but tuning is recommended if you want the cleanest result. Without tuning, many owners still notice a sharper throttle feel and a louder exhaust note, but a Check Engine Light is possible because the factory catalytic converters are removed.

• Without a tune: Expect a louder tone, quicker rev feel, and possible CEL depending on the rear O2 sensor readings.
• With a proper tune: The car can take better advantage of the freer-flowing exhaust, with smoother fueling, stronger mid-range response, and better overall drivability.
• Power range: A realistic gain is about 8-15 HP on a basic bolt-on setup, or about 10-20 HP with supporting exhaust upgrades and tuning.

Delivery, Return, and Protection