Dinan Free Flow Axle-Back Exhaust – BMW 135i / 135is (E82/E88)

OVERVIEW

Dinan's Free Flow Axle-Back Exhaust for the 135i Coupe and Convertible improves exhaust flow by reducing back pressure, which raises power output and delivers a sportier tone that stays civilized at cruise and turns pleasantly aggressive under harder acceleration. Drone abatement technology keeps cabin resonance in check so the added volume never becomes tiring.

The system is built entirely from 304 stainless steel to exacting specifications, so it mounts on the factory hangers and resists corrosion for years. The design also drops weight compared with the stock muffler and finishes with 3.5 in tips in polished stainless or ceramic black for a tasteful high-performance look.

SPECS

• Maximum gain: +6 HP @ 6600 RPM and +5 lb-ft @ 6600 RPM
• 100% 304 stainless steel construction
• Dual 3.5 in laser-engraved exhaust tips, polished stainless or ceramic black
• Drone abatement technology to reduce cabin resonance
• Lighter than the stock axle-back section
• Mounts using the factory brackets and hangers for factory-like fitment
• Shipping dimensions: 36 in L x 24 in W x 12 in H
• Weight: 32.5 lb
• Dinan labor time: 1.1 hours
• Emissions status per Dinan: legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles, because it does not affect vehicle emissions and is not covered by emissions regulations
• Dinan limited warranty: the remainder of the BMW new-car limited warranty, up to 4 years / 50,000 miles, if the vehicle is still covered by the factory warranty; otherwise 2 years / unlimited mileage. Wear items are excluded.

PARTS INCLUDED

• (1) Muffler
• (1) Clamp
• (1) Aluminum plug
• (1) Wire tie
• (4) Hairpin clips

TECH RESOURCES

Additional Parts Required

• None. Dinan specifies no additional hardware for this part; the clamp, plug and clips needed for the swap are supplied in the kit.
• Dinan notes rubber exhaust hangers should be replaced if the originals are worn.

Installation

• Dinan Free Flow Axle-Back Exhaust Installation Instructions (INS660-0025, Rev. 04/22/15) - PDF
• Dinan labor time: 1.1 hours

Notes

• Year and engine splits above are taken from Dinan's installation instructions.

PART NUMBER

• D660-0025-BLK - ceramic black tips

VEHICLE APPLICATIONS