Dinan Free Flow Axle Back Exhaust | 2020-2021 BMW X3M/X4M (D660-0086) Dinan

2020-2021 BMW X3M/X4M Stainless Steel Free Flow Axle Back Exhaust by Dinan

The “baby M’s” of the ‘X’ family just got a bit more big brother like. With more

volume and a deeper, more aggressive note courtesy of the Dinan axle back exhaust system, the F97/F98 now

stand on the precipice of rivaling, or even surpassing, its V8 siblings — at least, in regards to

sound. With an intoxicating and menacing sound befitting of a high performance SUV the X3M/X4M holds its

own amongst the pantheon of more traditional M’s.

In order to achieve the deep and throaty signature Dinan sound the system incorporates

larger 76mm tubing (vs 70mm stock) that allows freer flow through the entirety of the system but

specifically to both outer pipes when the enlarged valves are open. The resulting flow and sound mimics

an awe-inspiring straight pipe solution with a deeper, fuller tone, a defining element of all Dinan

exhausts. In contradiction to the aggressiveness resulting from open valves, when the valves are closed,

all gasses are forced into the muffler for sound deadening and exit the two inner tips. Regardless of

valve position, the intimate nature of the interior is retained so conversation can continue without an

excessively loud drone courtesy of drone abatement technologies housed within the can. With the Dinan

exhaust equipped on the X3M/X4M you get the best of both worlds; aggressive tone/sound and civility

Perhaps equally important to the sound of the installed Dinan axle back system are the

resulting aesthetics. With a nearly perfect symmetrical design, the raw muffler and pipe routing are

pleasing to the eye even when the matching proportions are only partially visible after install. The

piping culminates into four massive 114mm (4.5″) tips that fill up the previously spacious factory cut

out in the valance without appearing to be oversized and unnatural. The imposing tips utilize a new tip

design with an inverted clamp neck.

The new style allows for two very important things to happen. The first is the ability

to have a longer tip sleeve length without sacrificing real estate for a clamp neck thus allowing larger

tips even when there is limited straight pipe to clamp on to. Secondly, the interior clamp neck means

that the clamp itself is almost completely hidden from view for an unblemished install. Dinan has

retained its signature straight cut tip design, safeguarding its unique and elegant styling position

amongst a crowded marketplace full of angle cuts. With systems available with either black ceramic coated

or polished clamp-on, and laser engraved exhaust tips, there is a version that is sure to meet your

individual aesthetic needs.

Features

• Quad 4.5″ (114mm) diameter clamp-on, double-walled, polished or black ceramic and laser engraved

  exhaust tips

• Tuck-it tip design ensures a nearly flawless and unencumbered visual appearance
• 100% 304 brushed stainless steel construction w/ TIG welding
• Larger diameter piping for increased flow
• 5 lbs lighter than the stock system
• Computer controlled exhaust valves retained, limiting noise during low speed driving and opening

  fully during high-load conditions

• Twin exhaust valves are a whopping 76mm diameter, making them 30% less restrictive than the OE

  valves

Benefits

• More Power: +8 HP @ 6600 RPM, +6 FT-LB @ 6600 RPM
• Enjoyably louder, sportier sound
• Easy bolt-on installation with included mounting hardware

Applications

• 2020-2021 BMW X3M
• 2020-2021 BMW X4M

What’s In The Box?

• 1 – Free Flow Axle Back

References

• Installation

  Instructions

Warranty

• Manufacturer Standard Warranty