POWERFLEX Black Series BMW M4 F82 F83 Dual-Mount Rear Differential Bracket

Background to POWERFLEX

EPTG Ltd (European Polyurethane Technologies Group) was formed in the UK in 1996 to take advantage of the significant advances made in the development of polyurethane in recent years.

The company has wide experience in automotive suspension and chassis systems and combining these design skills with advanced polyurethane manufacturing techniques led to the development of a wide range of high performance automotive polyurethane components now known the world over by the product name POWERFLEX.

The stainless steel components are machined on the latest computer-controlled equipment to ensure perfect repeatability and quality.

The moulding and tooling, design and manufacturing are carried out within the factory ensuring very rapid response time to special projects and complete communication between development, prototyping, testing and manufacturing departments. Component manufacturing is carried out with the latest automatic processing equipment ensuring 100% right-first-time quality. Testing of new components is carried out both on the vehicle and on test rigs.

All of these factors combine to make Powerflex the number one performance bushing.

BM Performance Centre stocks and sells both Road Series and Black Series bushes (for track and motorsport use) and suspension components.

Road Series – for Road and fast Road use.

POWERFLEX Road Series bushes improve your cars’ road holding and chassis performance by controlling the amount of unwanted flex in the suspension. This means the suspension is doing what it is supposed to. It means your tyres have greater contact with the road at all times, therefore, improving safety and performance. Correctly formulated polyurethane is as good if not better at noise, vibration and harshness suppression when compared to worn rubber. Our Road bushes offer Prolonged tyre life, Improved performance, Increase safety, and Greater cost-effectiveness.

Black Series – for Track and Motorsport use.

POWERFLEX Black Series bushes are manufactured using our Black 95 Shore A compound to provide maximum control of chassis geometry. They are designed for the Track, ready to Race and are engineered to be the best. This compound can be up to 80% more resistant to load than standard rubber and 25% stiffer than our purple performance material. If your requirements are purely for the ultimate in handling and chassis performance then Powerflex Black Series are unique, offering the most precise and accurate alignment for your chassis.

OUR MATERIALS

Our materials are colour coded to make them easily identifiable. Below explains the shore rating and their common uses.

Red 65A – Used for our Universal exhaust mounts and diesel engine mounts.

Yellow 70A – Mainly used for engine mounts, diff mounts and subframe mounts or areas where the bush needs a lot of movement and absorption.

Purple 80A – Our most common material. This is used in most areas of the suspension and provides the right mix between performance and compliance.

Black 95A – Our hardest material. This is used mostly for our Black Series range or in our Road Series where the vehicle’s standard suspension demands require us to use this hardness of material i.e. in areas of high load.

This is a replacement part that uses our Black Series material to boost stiffness over the original part by 18% to withstand increased loading seen by this position on the car. 

Supplied complete with M14 bolt, thread locker and Powerflex keyring. The bracket comes on its own without bushes, so you can choose to use it with a variety of bush combinations. Single OE bush, Dual OE bushes, Single OE bush with single PU bush (1 x PFR5-4026) or Dual PU bushes (2 x PFR5-4026). We would recommend dual PU bushes ideally. If you wish to use it with a single OE bush with a single PU bush, then the PU bush would fit in the vacant right-hand mounting hole in the subframe. 

With the newer F8x M2/M3/M4s making big power and having superb chassis straight from the showroom, it's no wonder they're often found at the most serious of track-days or at tuning shops across the globe. 

Unfortunately, the power that makes these cars so fun to drive eventually has an impact on the vehicle components, most notably the rear differential bushes.

Despite having the provision for two mounting bushes on the factory tubular subframe, BMW opts to use only a single offset bush to mount the diff bracket to the subframe. This essentially creates a pivot point for the diff under torque loading, especially if the 4x front diff bushes are worn and softened. 

With hard launch starts and sudden and frequent on-off throttle changes, this puts the single rear OE rubber bush through extreme torsional and directional forces, resulting in accelerated ageing with failure often seen at around the 30-40,000 mile mark and an unsettled and potentially clunky rear-end. 

We are proud to release a high-performance solution to this problem, giving you the tools to re-establish rear-end stability on your F8x M2/M3/M4.

PFR5-4030 Dual Mount Diff Bracket is made from our in-house CNC machined 6082 High-Tensile Aluminium and is designed to utilise the secondary mounting position on the OE subframe. With the addition of a second bush, this prevents the diff from twisting under load, providing benefits such as:

• Reduced drivetrain movement
• Improved throttle response
• A more controlled and consistent on-off throttle chassis response. 
• Improved tyre-to-road power transfer reducing wheel hop
• Reduced strain on fitted bushes 

The corrosion-resistant Satin Black Anodised Aluminium Bracket is optimised for high stress and deflection whilst withstanding high torque loads but is designed to function equally on standard or modified vehicles with either a single OE bush or dual aftermarket bushes. Although the bracket can be fitted without the need to remove the subframe from the vehicle completely, we would naturally recommend combining Powerflex products by using our already hugely popular 80A durometer PFR5-4026 Rear Diff Mounting Bush for both subframe rear mounting positions with the addition of our PFR5-4025 Rear Diff Front Mounting Bushes for the front for the ultimate in differential control and a lasting fast-road or track solution. 

PFR5-4026 bushes can be fitted with our PFR5-4030 dual-mount rear differential.