KRATOS KRAS55 Turbo Upgrade Kit For BMW S55

Greek God, KRATOS, is the personification of Strength and Power in Greek mythology. This ethos has defined the direction of the KRATOS brand.

KRATOS came into conception through a group of engineers with 25+ years of private label design and manufacturing turbo systems for various house-hold name performance brands. These engineers saw a untouched segment in the high end European market for True OEM Style Dual Ceramic Ball Bearing Turbo System Manufacturing and through that revelation the KRATOS brand was born.

KRATOS systems are forged from the finest raw materials and assembled with strenuous attention to detail. Every component is purposefully designed and engineered-in-house and tested to extreme standards. KRATOS is The Only True Dual Ceramic Ball Bearing OEM Fit CORE-LESS Turbo System Manufacturer.

KRATOS aims to provide exclusive turbo systems for premium European performance vehicles. This goal is achieved through pride and purity of engineering as well as uncompromised use of top tier materials and manufacturing methods.

KRATOS was recently acquired by Global Motoring Group LLC, not to be confused with racing company GMG. This has further emphasized the focus of the KRATOS brand is to provide OE fit turbo solutions to top tier European performance cars.

Technical Summary:

Ceramic Ball Bearing Cartridge (Patent Pending):

KRATOS ceramic ball bearing technology encompasses industry leading technology in an OE fitment package. The use of ceramic ball bearings in true OE fit cartridges is entirely unique to KRATOS. This translates into ease of ownership and increased performance for the end user.

  • 5x the service life of steel ball bearings.
  • Significantly lower operating temperatures than steel ball bearings.
  • Increased efficiency and thrust load capability.
  • Near frictionless operation requiring minimal oiling.
  • Heightened transient response.


One Piece Turbofold (Patent Pending):

The cornerstone of the KRAS55 line of turbos, the completely re-engineered one piece turbofold is a part of the reason of safe power can be achieved. The turbofold reduces backpressure significantly, making engine operation at higher output safer and more reliable. In testing, data proved a 1.1:1 Backpressure rating at 32psi. A car making 32psi of boost would see 35.2psi of pressure on the manifold side. This allows for the engine to cycle without additional stress of vacating spent exhaust through a manifold with high resistance. If not addressed, excessive back pressure causes undue stress resulting connecting rod failures as well as loss of power and engine efficiency.

Mathematically matched A/R ratio.

  • Reduced heat and increased turbine efficiency.
  • Smoother internal runner transitions.
  • Increased runner diameter.
  • Computational Fluid Dynamics modeling software tested.
  • 316 Stainless Steel.


OEM Fitment and Core-Less Design:

The integration of ceramic ball bearing technology into true OEM fitment is unique to the KRATOS brand. Like all other KRATOS line of products to follow, the KRAS55 series retains use of factory oil and water lines without use of adapters of any sort. Many customers may weigh downtime and core usage as important factors in their buying decision. KRATOS products allow customers to retain their cores for whatever use they prefer and create no downtime other than installation.

  • Utilization of OEM Oil + Water lines.
  • Full reversibility.
  • Full compatibility with OEM fit aftermarket parts


S55 Specific Inlets:

The factory S55 turbo inlets at their narrowest point have an internal diameter of 42mm. This poses a problem if a compressor wheel with a larger inducer diameter is used. To address this, all KRAS55 turbo systems include a set of custom designed 4 ply silicone inlets as well as a matched ported billet aluminum elbow which are designed to support flow capabilities of even the larger wheel options.

  • Direct fitment to OEM crankcase ventilation and intakes.
  • Custom Designed 4-ply silicone inlets.
  • Polished and match ported billet aluminum elbow.


Compressor Wheels:

KRATOS compressor wheels are in a league of their own. Each compressor wheel is designed and tested in house for each specific application in mind. These compressor wheels will only be found on KRATOS products and hundreds of hours have been spent on testing and design in order to match the intended use. KRATOS also performs shaft speed testing to ensure that compressor designs are not being run beyond their efficiency range or flow capabilities..

There are currently two options for compressor wheels on KRAS55 turbo systems:


KRAS55Bi: 850+whp

  • Forged Billet Aluminum
  • 3rd order Geometry Design
  • Point Milled Manufacturing

For those who intend on keeping their internals stock, this may be the best option. This system is capable of supporting 850whp+ and allows for safer and reliable operation over 700whp on the stock engine.


KRAS55Ti: 1,000whp+

  • Forged Billet Ti6Al4v Titanium (Grade 5)
  • 3rd Order Geometry Design
  • Point Milled Manufacturing

This wheel is intended for use on built motor high output setups. Titanium’s higher tensile strength over that of aluminum allows for more aggressive design characteristics. The Titanium material is also great for road race or endurance racing applications where HCF (High Cycle Fatigue) can pose issues. More information and data results will be available as release of the KRAS55Ti approaches.



All KRATOS products have a limited 2-year warranty from date of purchase that covers all manufacturing defects.


Models Supported:
BMW F8X M3 & M4

To order yours, please click on the link below.

KRATOS - KRAS55 Turbo Upgrade Kit - BMW S55