Project Gamma High-Flow Downpipes for BMW M5 G90 & G99 (S68 Twin-Turbo V8) – 304 Stainless Steel, CNC Precision

Upgrade your BMW M5 G90 Sedan and G99 Touring with Project Gamma’s high-flow catless downpipes, engineered for maximum turbo efficiency, power, and response. Crafted from premium 304 stainless steel with precision CNC-machined V-band transitions, these downpipes are built to withstand demanding performance driving and deliver measurable gains when properly tuned.

Unlike many competitors that neck down piping closer to the turbo outlet, our design maintains a smooth 3D-bent flow path all the way through, unlocking improved exhaust velocity and reduced backpressure for stronger spool and throttle response. When paired with a proper ECU tune, this upgrade can deliver significant horsepower and torque increases compared to stock exhaust manifolds.

Key Features & Benefits:

• Precision CNC-Machined V-Band & Flanges for a secure, leak-free fitment.

• High-Flow Catless Design optimized for turbo efficiency and reduced backpressure (tune required). 

• Premium 304 Stainless Steel Construction for corrosion resistance and long-term durability under high temperatures.

• Enhanced Turbo Response & Reduced Lag through optimized exhaust flow. 

• Exotic, Aggressive Exhaust Tone that complements performance-oriented driving. 

• Handcrafted & TIG-Welded for precision and strength. 

Perfect For:

• Enthusiasts looking to unlock more power and throttle response on tuned BMW M5 G90 / G99 platforms.

• Track-oriented builds and performance upgrades where full exhaust flow is critical. 

Fitment:
✔ BMW M5 G90 Sedan (S68 Twin-Turbo V8)
✔ BMW M5 G99 Touring (S68 Twin-Turbo V8)

If your item is in stock and the order is placed before 3 PM, it will ship the same day. Products that include ceramic coating are shipped the following business day. If the product or color you’re looking for is out of stock, you can join the waitlist by clicking the “Email When Available” button. We’ll notify you as soon as it’s back and provide an estimated restock time.

Custom Orders
For custom requests, please email us directly. We’ll review your order and provide an estimated delivery time based on the required manufacturing process.

Damaged, Incorrect, or Missing Items
If your order arrives damaged, incorrect, or missing parts, simply email us a photo along with your order number. We’ll arrange a refund or exchange right away. Contact us at info@ttmengineering.se and we’ll make it right.

Returns & Satisfaction
Unused and uninstalled products are eligible for a refund, exchange, or store credit. Unfortunately, once a product has been used or installed, we cannot accept returns or offer refunds. If you decide you don’t like a product after installation, it will not qualify for return.

Restocking Fee
A restocking fee of 20% of the original purchase price may apply to returned products. This fee covers the costs of processing and restocking. Please refer to our Policies Page for full details on exchanges and returns.