BMW M325i 2007

Service Completed: Custom Cat-Back Exhaust Upgrade

At MIJ Exhaust Ltd, we recently completed a bespoke exhaust upgrade on this BMW 325i (2007) 2.5L Petrol, designed to enhance sound, improve exhaust flow, and refine the overall driving experience.

This build featured a custom cat-back system, replacing the factory rear sections with a freer-flowing setup designed to reduce restriction and allow the inline-six engine to breathe more efficiently. The result is a smoother, more responsive drive with a deeper, more engaging exhaust note that brings out the natural character of the 2.5L petrol engine.

The upgraded system delivers a more pronounced sound under acceleration while still maintaining a refined tone during normal driving, making it well-suited for both everyday use and spirited driving.

As with all of our exhaust systems, this setup was hand-fabricated in-house using high-quality T304 stainless steel and fully TIG welded, ensuring excellent durability, corrosion resistance, and a precise, long-lasting fit.

Be sure to check out the before and after images to see the transformation, and watch the video to hear the sound test and see the completed work in action.

https://www.instagram.com/p/DWbG5Uwj6SG/

Why Choose a Custom MIJ Exhaust?

No two vehicles—and no two customers—are alike. That’s why every exhaust system we build is custom-made on the vehicle for the perfect fit, tone, and performance.

Whether you’re after:

A sportier, more aggressive sound,

A performance-focused setup, or

A refined, OEM-style tone,

—we tailor the design specifically to your goals.

More Than Just Custom Builds

We provide all types of exhaust services, including:

Exhaust repairs and leak fixes

Section replacements

Welding cracks and fault correction

Tailpipe upgrades and cosmetic enhancements

Small adjustments and one-off jobs