BMW M3/M4 (G80 | G82 | G83) Axle Back Stainless Steel Exhaust System

The Project Gamma Catback Exhaust system for the BMW G80 M3 and G82/G83 M4 models drastically improves the vehicle’s exhaust note and enhances performance by featuring a performance muffler that reduces the restricted exhaust flow. The valved design allows for the use of the factory valves and retains all valved features.

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.