The Ultimate
Modular S85 Carbon Plenum
One of the most challenging intake systems to design and manufacture to date and our showcase product.
The BMW E60 M5 CSL has always captivated the hearts of S85 owners with the showcase being the single piece carbon plenum with larger side inlets running AlphaN software.
It was never available as a part to purchase.
We did not want to make just make another carbon plenum which replaces the OEM for noise alone.
Like the rest of our range we wanted to give the enthusiasts something very special for what is essentially one of the last of the truly great naturally aspirated engines.
Infinity Design therefore went the extra distance to give the enthusiast S85 owners something special.
The 100% pre preg carbon fibre plenum was designed in CAD software using accurate 3D scans of the engine bay without the OEM plenum in place, 3D scans of both of the individual OEM plenums and then combined together to make a singular larger volume system.
The induction sound is beyond what has been achieved by the market.
Mutiple reports of the intial pre production batch have shown more usable torque and improved 60-130mph times as well as improved power on dyno testing.
Under bonnet looks are sensational.
At the core of the design is the modularity. This is key both to the functionality, how the system is fitted, the multiple upgrade paths and also a lower price. No other product throughout the BMW aftermarket exists which is this complex and at the same time gives so many options and advantages.
Modular Design
Modularity allows the ability to upgrade or specify their configuration
The standard plenum is supplied with OEM style side inlet which will fit to the following:
– OEM Intake System
– Infinity Design Intake
– Any aftermarket intake designed to fit the OEM plenum
This can be upgraded to:
1. Full CSL specification which uses larger side inlets and a bespoke larger intake system.
2. Velocity stacks can be replaced to shorter or larger types for a different torque curve
Alternatively the full CSL package can be ordered from the outset.
Specifications – OEM Intake
100% Pre Preg Carbon Construction
Modular Design allowing interchangeable larger side inlets and velocity stacks
1 x Modular Carbon Plenum Body with CNC Fittings and internal Oil Separators
1 x Carbon Lid
Left Inlet Tube with integrated MAF Boss
Right Side Inlet
Left Side Inlet
10 x Carbon Velocity Stacks
Full Fitting Kit
Supplied with AlphaN Tuning
Available in Gloss and Matte finish
Resistance to Failure
It has been long known that carbon plenums suffer from internal failures. The most common issue is the velocity stacks break away as they are often glued. Over time the adhesive weakens with heat cycles and vibrations. Not only is the entire plenum wasted but can cause major catastrophic engine damage as the broken carbon shards entire into the combustion chamber.
The Infinity Design system has one piece velocity stacks which are bolted through the plenum into the throttle body bosses. There is no chance of failure.
The Oil Separator Housings are replaceable should they fail and due to the design allowing for the lid to be removed, these can also be serviced or replaced.
Fitment
The fundamental problem with one piece plenums is that they are very difficult to fit as the throttle bodies are at a 120 degrees angle to one another unlike the S65 engine where they are at a 180 degree angle and the plenum fits directly downwards on top of them.
A solid one-piece plenum causes major issues when attempting to fit with the rubber boots not seating correctly onto the adaptors on the plenum which lead to major air leaks. The system also requires considerable force to seat correctly.
The Infinity Design plenum allows the throttle body bosses to first be attached to the rubber boots, the main plenum is placed onto the adapters, the velocity stacks are then attached, side inlets installed and lid installed leading to a leak free and simple process.
By keeping the main frame, throttle body bosses, velocity stacks, side inlets and lid separate a logical and simple process can be taken to fit the system giving no risk of overlapping of the throttle body boots which leads to air leaks and having to force the plenum into position
Dyno Testing
Initially never designed for increased power, the by product of increased plenum volume and optimised velocity stacks has been gains in power under dyno testing.
Road performance improved with improved throttle response and partial load torque.
The full CSL specification has shown peak gains of 15-20HP without power tuning and only AlphaN fuelling strategy.
Dyno graph shows S85 previously tuned with :
stock intake + tuning vs CSL intake + AlphaN
Pair with CSL Intake Upgrade for the Ultimate Intake System
100% Pre Preg Carbon Fibre
AlphaN Tuning Required
