Even though BMW S55 engine found in the new BMW M3 and BMW M4 delivers more power than most drivers can handle, there are certain tuners out there that feel more power is needed. California-based Dinan releases a tuning package for the BMW M3 and BMW M4 engine which includes a free flow exhaust that helps boost the engine’s power and torque.

Dinan aimed to enhance the engine’s exhaust note, perfecting the sound coming out of the quad exhaust pipes. Dinan’s Bolt-On Free Flow exhaust system features 16 gauge 304 stainless steel construction measured to exact specifications to ensure the proper fit and will resist corrosion for years to come. This system was designed to produce a more aggressive sound under acceleration, accompanied by more horsepower.


The exhaust gasses exit through the laser engraved quad 3.5 inch ceramic black or polished stainless steel exhaust tips. Dinan’s Free Flow exhaust system features twin secondary exhaust valves with a whopping 76mm diameter, making them 45% less restrictive than the OE valves. Computer controlled valve actuation has been fully retained for a civilized low-volume experience in Econo mode and high-volume unrestricted performance in Sport and Sport+ modes. This combination nets your M3/M4 an additional 5 horsepower and a weight reduction in excess of three pounds.


Dinan has also launched its adjustable coilover system that offers a substantial reduction in body roll as well as reducing dive under braking and squat under acceleration. Dinan’s design keeps the factory Electronic Damper Control shocks in place and implements threaded collars to allow the user to change the ride height. The end result is a sleek, lowered stance that provides improved handling to go along with its stunning visual appearance.


The springs combined with progressive bump stops and other components increase travel that allows the car to be lowered up to 1″ in the front and 1 1/2″ in the rear, with spring rates being increased by 50% in the front and 10% in the rear. Suspension packers are included to fine tune handling and comfort by changing the clearance of the progressive bump-stops, something no respectable performance car is without. Components are machined from 6061-T6 aluminum and black anodized for appearance and corrosion protection. Dinan will guarantee you superior handling, performance, and comfort.

This exhaust system comes with their factory matching new car warranty and is designed, developed and tested in Morgan Hill, California and can be purchased and installed at any Dinan Approved BMW dealerships nationwide. See more photos below.