Dinan Free Flow Axle-Back Exhaust System with Polished Tips for BMW M340i / M440i 2020-2024
The Dinan Free Flow Axle-Back Exhaust System for the G20 M340i and G2x M440i introduces quad exhaust tips to models that previously sported dual tips, signaling an exciting shift for these performance cars. While some may question the implementation of quad tips on a "pseudo-M," Dinan believes that the M340i/M440i, powered by the impressive B58 engine, deserve the same aggressive styling and performance enhancements as their full M siblings.
Key Features:
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Performance Gains: +6 HP and +5 lb-ft of torque at 6600 RPM.
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Quad 4" Exhaust Tips: The system features massive 102mm clamp-on, double-walled, polished or black ceramic-coated tips with Dinan’s signature straight-cut design. These tips perfectly complement the factory valance and deliver a unique, aggressive aesthetic not often seen on non-M models.
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Increased Flow and Performance: The system uses larger 76mm piping (compared to the stock 70mm), which allows for greater exhaust flow and improved performance. The result is a deeper, meatier tone, mimicking a straight-pipe system with none of the harshness.
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Dual Exhaust Valves: The factory system only includes one valve, which silences the passenger-side exhaust tip during quiet operation. Dinan's system adds a second valve, ensuring even exhaust flow through both outer tips when open and directing all gases through the muffler when closed for a more subdued sound. This configuration results in both enhanced performance and sound control.
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Drone Abatement Technologies: Despite the increased exhaust flow, Dinan's design incorporates drone abatement technologies to maintain a quiet cabin, allowing for conversations and a refined driving experience without excessive interior noise.
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High-Quality Construction: The exhaust is crafted from T304 stainless steel, TIG welded, and brush finished for durability and a premium look. It’s also 4 lbs lighter than the stock system, improving both performance and weight distribution.
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Stock Valve Control Retained: The system retains the factory computer-controlled exhaust valve actuator, and an additional valve/actuator is added to the opposing side to ensure symmetrical flow and sound management.
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Easy Installation: The exhaust system is a simple bolt-on upgrade, designed to use the factory hangers and comes with all necessary mounting hardware.
| Brand |
Dinan |
| Dinan Point Value |
3 |
| Emission Code |
5 |
| Height |
10 |
| Labor Time (Hours) |
2.5 |
| Length |
54 |
| Max HP Gain |
6 @ 6600 RPM |
| Max Torque (lb-ft) Gain |
5 @ 6600 RPM |
| Product Type |
Axle-Back Exhaust |
| Tip Finish |
Polished |
| Weight |
68 |
| Width |
29 |
| UPC |
813725028767 |
| Part Number |
D660-0085 |
Fitment Chart:
| Make |
Model |
Year |
BMW
|
M340i
|
2020-2024
|
|
BMW |
M340i xDrive |
2020-2024 |
|
BMW |
M440i |
2021-2024 |
|
BMW |
M440i xDrive |
2021-2024 |
|
BMW |
M440i Gran Coupe |
2022-2024 |
|
BMW |
M440i xDrive Gran Coupe |
2022-2024 |
⚠️ California Proposition 65 Warning:
This product may expose you to chemicals known to the State of California
to cause cancer or reproductive harm.
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