Stone Exhaust BMW M3/M4 S55 F80 F82 Valved Performance Catback Exhaust - OEM Integrated Valve, ECU Controlled, No Drone - AP507

Stone Exhaust AP507 for BMW F80 M3 and F82 M4 S55

Transform the soundtrack and response of your twin turbo S55 with the Stone Exhaust AP507 rear system. This flap controlled cat back keeps factory valve functionality through the ECU, gives a richer motorsport tone, and remains calm on the motorway with zero cabin boom. If you want a premium BMW M performance upgrade that fits like original equipment and sounds incredible without compromise, this is it.

What you will love

• Factory valve integration, uses the car’s original flap motors and drive modes for seamless operation
• Deep, refined note at idle and cruise, aggressive and crisp under load with no drone
• True bolt on fit, developed from full 3D scans of the OE layout for precise alignment
• One piece layout with machine perfect welds for strength and longevity
• Dyno proven gains for genuine performance you can feel
• Optional Valvetronic controller available for remote valve control via simple OBD plug in

Real world results

• Power gain: +12.2 PS at 6800 rpm
• Torque gain: +9.8 Nm and +7.2 ft lb at 2500 rpm

Engineering first approach

Stone engineers start by 3D scanning the original pipework to lock in routing and diameter. Flow is then refined using simulation to optimise gas speed and reduce back pressure. 7 axis CNC bending maintains up to 98 percent roundness through the bends for low turbulence. Critical joints use crisscross and overlapping welds for heat resistance, and automated spot welding ensures consistency across every AP507 system.

OPF and GPF ready

Running a particulate filter car. Stone can include an OPF or GPF delete function free of charge, allowing installation on equipped vehicles without error messages. No ECU coding for the filter is required.

Perfect pairings

Unlock the full potential of the S55 by combining this cat back with the Stone S55 downpipes. Add the Stone Valvetronic controller for handheld valve operation in addition to the factory modes.

Compatibility

For S55 powered BMW M models:

• F80 M3 Saloon 2012 to 2015
• F80 LCI M3 Saloon 2015 to 2018
• F82 M4 Coupe 2013 to 2017
• F82 LCI M4 Coupe 2016 to 2018

Required parts for installation

You will need the following additional items to complete the install:

• 2x Genuine BMW S55 downpipe gasket, exhaust side for M2 Competition, M3 and M4
• 4x Genuine BMW F10 F80 F87 G15 catalytic exhaust centre collar nut, M8 including M550iX, 760i, M850iX and M6

Fitting

We recommend professional installation. Book with MJ Modifications in Warwickshire for expert fitting and setup. Request a quote by emailing info@mjmodifications.co.uk.

Why buy from us

We have installed this system on S55 cars and the feedback is consistently positive. Customers comment on the premium tone, the drone free cruise, the perfect fit and the noticeable improvement in response. It looks as good under the car as it sounds from the driver’s seat.

Manufacturer and warranty

Produced by Stone Exhaust with a 2 year warranty.

Part number

AP507

Search terms customers use

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