BorgWarner EFR Turbocharger Overview








We’ve been working on something we think is really exciting…

As an organization, Full-Race is committed to constant improvement. We work every day to “Raise-the-Bar” in the engineering and fabrication of performance boosting systems for the automotive aftermarket. Our obsession with achieving ever higher levels of performance has driven us to create our legendary turbo kits (all in-house!).  Today, Full-Race is recognized world-wide as the premiere manufacturer of Robotic-TIG welded turbo manifolds and the leaders in TwinScroll turbo kit technology.


Attaining this position in the performance engineering marketplace has not come easily. Many long days and nights of experimenting, testing and breaking parts parlayed into months and years of experience. During this time the level of competition has vastly increased while many facets of vehicle technology quickly improved. We’ve seen the likes of new engine management systems, improved fuel injectors, better suspensions, stronger gears & driveshafts, and smoother clutches – just to name a few. Yet the turbocharger, arguably the most important horsepower-generating component in the modern internal combustion powered performance vehicle, remained virtually unchanged. Until now…

The Next Generation of Engine Boosting Devices

BorgWarner turbocharging systems have deep roots in the world of high performance – from their being the OEM for Porsche, BMW and Audi – even the is theirs.   The hard working psycho-heavy-duty applications like John Deere and CAT rely on Borg Warner for their engine boosting requirements.



Fast forward and Full-Race starts experimenting with the AirWerks journal bearing turbos S200SX, S300SX, and S400SX. These simple journal bearing turbos impressed us by how well they performed, especially considering their simplicity and value-minded pricing. No ball bearings nor watercooling, and we ran them in Time AttackDrag Race and Drift cars with outstanding durability and response.












Soon after, we had the opportunity to visit Asheville, NC – the home of BWTS (BorgWarner TurboSystems). This was an incredible experience that I can only be compared to being at Willy Wonka’s Turbo Factory. After learning of what Full-Race was doing with the AirWerks turbos, the BW engineering team approached us to inform us of a completely new idea. Their primary focus was to “reinvent the modern turbocharger” from the ground up. Something capable of high boost levels, huge airflow and extreme durability requirements, yet still producing improved driveability, outstanding power and quick response at lower boost levels and low engine/shaft speeds. Spooling fast and keeping huge power potential? Uhhhh… EVERY enthusiast wants that!!! We were all ears.





The engineers at Borg Warner started from a clean slate, every component of the turbocharger was re-evaluated. A list was compiled of every great design feature in existence – then added new ideas, some never before seen. They felt the turbocharger of the future should serve many different roles. Not only will the turbo be an “air pump” but it can also have integrated features designed to minimize, or in some cases eliminate, additional components in the turbo system – saving time and money while reducing installation effort. The turbocharger of the future should be versatile – capable of fitting a variety of different engines, multiple cylinder configurations, integrated manifolds or traditional exhaust manifolds, twinscroll or singlescroll and of course multi-fuel compatible. Convenient features such as a traditional 2.5″ compressor hose outlet or easily convert it to an integrated vband outlet. Many other advanced design elements were added to the turbos such as pre-machining for a shaft speed sensor – data that is very important in determining proper performance or troubleshooting of any turbo car (yet very few log). One of the major areas for improvement was found through countless hours of high-tech aerodynamic work. Blade aerodynamics were developed from the ground up to result in a lineup of optimally matched ultra-efficient turbochargers suited to high-power modern spark ignition engines. These were then further combined with top-shelf materials to allow for market-leading performance, and we at Full-Race couldn’t be happier.




We at Full-Race are honored to have been involved with Borg Warner in such an evolutionary step in the world of turbocharging. The release of BorgWarner’s EFR series turbos marks the fastest spooling and quickest responding turbochargers ever available to the automotive aftermarket. The turbos are built in different sizes, to suit the application at hand BorgWarner EFR Turbochargers installed with Full-Race EFR Manifolds will be on display at SEMA in Las Vegas, NV and PRI in Orlando, FL.

Sierra Sierra Time Attack Evo

The Sierra Sierra Time Attack Evo is powered by our Full-Race Twinscroll Turbo kit. For years their team battled turbo failures. BW engineering saw this as an ideal test bed where twin-scroll BorgWarner EFR8374, 9174 and 9180 turbochargers could be fully evaluated. Soon after, the EFR powered vehicle re-wrote the record books with a 298km/h top speed record at World Time Attack at Eastern Creek in Sydney, Australia.







There are nine (9) investment cast stainless steel turbine housings that make up the initial release of the EFR series (with more to come). Sizes are available in 0.64 and 0.85 A/R T25, 0.85 A/R V-Band in either internal or external wastegate configuration, 0.83 A/R T3, 0.80 and 0.92 A/R T4 internal WG, and 1.05 and 1.45 A/R T4 external WG. T4 twinscroll footprints, all use a 3″ Vband outlet. Stainless steel is a superior material choice for manifolds and turbine housings in turbocharged engines which operate at extreme EGTs. From a performance standpoint, the combination of material properties and thinly cast wall thickness allow less heat energy to escape AND are lighter weight while also being more crack resistant. The investment casting process results in a perfectly smooth surface finish that resembles a ported/polished cylinder head and serves to lower gas friction losses – all while looking beautiful in the engine bay (a perfect compliment to the Full-Race header it’s attached to). Stainless Turbine housings offer exceptional corrosion resistance at elevated temperatures – far superior to rusty/corroded cast iron housings we are used to seeing in the past. These turbine housings are truly fit for street use, road racing, or even endurance racing and when polished they look like modern-artwork.

NOTE: These are NOT designed to be direct bolt-in replacement turbine housings for other mfg turbos so do NOT expect them to bolt up to your car/manifold without changes unless stated.



The optional EFR internal wastegate is truly designed for high flow, even for big-power setups. EFR optional internal wastegates are aerodynamically-optimized to offer the same performance as an external wastegate recirculated back into the downpipe – no 90 degree corners here. This is a real “value” feature of the EFR program, particularly in the case of twinscroll applications which require (2) external wastegates, (2) manifold wastegate ports (2) dumptubes for maximum performance. Furthermore, the manifold fabrication and installation are both simplified with the wastegated EFR models. Boost levels can be easily adjusted by swapping adjustable wastegate canisters available in three different spring rates/boost levels. Lastly, different turbo clocking positions are easy to accommodate without changing the wastegate bracket. This is because the bracket is bolted to the bearing housing backing plate – not to the compressor housing as is the case with most internal WG turbos. For space constrained applications which can not fit the EFR internal WG or Hardcore racers that want to keep their dual external wastegates mounted to the exhaust manifold – you can do that too!

EFR Internal WG Fitment is application specific: most longitudinal engines such as 2JZ, SR20, RB26, will fit the Internal WG, whereas many transverse engines such as some FWD Hondas and some AWD applications will not fit the EFR internal WG. Applications prone to boost creep may prefer large external wastegates for boost levels under 7psi. exceptions to the rules confuse this. Keep an eye out for a Full-Race fitment compatibility chart coming soon!

Cold Side (Compressor)

All EFR turbochargers use Extended Tip Forged Milled Compressor Wheels ***AKA Billet Compressor Wheels*** The seven EFR compressor wheels range from 62mm OD (~50mm inducer) to 91mm OD (~67mm inducer). These Extended Tip Technology designs are unique in that they are BorgWarner’s highest-boost capable wheel designs yet still produce outstanding map width and flow capacity for efficiency at all boost levels and engine types. EFR compressor wheels are manufactured from forged aluminum for maximum strength and light weight, then CNC machined on a 6-axis CNC Mill. The blade geometry utilizes State-of-the-Art aerodynamics that delivers efficiency, boost capability and surge limits beyond any turbo we have ever seen. The forging strength exceeds that of typical aluminum billet bar-stock and also exceeds the material properties of an aluminum lost-wax compressor wheel casting. These compressors define “top shelf” in terms of strength, efficiency, range/width, and of course pressure ratio (boost) capability.



EFR turbo compressor housings incorporate an integrated BOV. Yes, you read that right – the BOV is a recirculating style *built-in* to the Compressor Housing. The major performance advantage in this design is that it redirects the high-pressure compressed air from the outlet of the compressor wheel -> right at the low-pressure inlet of the turbo. This helps to keep the turbo spooled between shifts and offers cost savings/convenience while keeping MAF-based engine mgt happy. With this in place, there is no need for a BOV or flange on the charge piping. The only downside of this feature is the fact that it makes the compressor housing about 1″ (~25mm) longer in axial length. For the hardcore racers who want to use an external traditional BOV, and for applications that can not fit or do not want to use the internal valve, we offer a disabling cover plate. This cover plate installs in place of the plastic cover and uses the original diaphragm to seal the port.

There are three compressor housing sizes and types – All housings come with the same features BOV, BSCV, V-band connection, hose clamp surfaces, etc. The first is a small compressor housing for the T25 turbos. The medium is used with the mid-sized 70mm and 76mm OD compressor wheels available. The large compressor housing is used with the 83mm and 91mm wheels. Lastly, exclusive to the large cover is a dual-machined outlet, useful for both a hose connection and/or a v-band connection. If the v-band feature is needed, the hose connection portion can be cut off and discarded. Full-Race will offer vband 90 degree bends for applications which require a tight bend, close to the turbo (such as RB26 and many Subaru rotated setups). The medium and large housings both use an inlet recirculation groove (AKA ported shroud) for maximum compressor map width and anti-surge characteristics.



A Boost Control Solenoid Valve (BCSV) is included with every EFR turbo — For electonically controlled boost levels, an Electronic Boost Control Solenoid (EBCS) is integrated right into the compressor housing. This solenoid is truly OEM quality and uses an industry standard fuel injector plug, making it easy to connecting to multiple boost control systems. Of course if the hardcore racers want to use an external solenoid OR a manual boost controller (without the integrated EBCS), that is very easy to do.



Speed Sensor mounting provisions are also supplied on every compressor cover (speed sensors are sold separately). Turbo speed sensors are not new technology, but the installation procedure has always been difficult for even the most experienced tuners/installers. Traditionally the customer must remove their compressor cover and take it to a machinist. This machinist then has to set up the cover at a compound angle to precisely drill the speed sensor bore while carefully hitting the contour area of the wheel bore at the right angle. The BorgWarner EFR solution provides this precision machining already done to every compressor cover. The hole stops short of protruding into the compressor wheel bore. If a user decides to buy a speed sensor as an upgrade accessory, they simply remove the compressor cover and extend the hole the rest of the way through to the wheel bore using a hand drill. A ¼” drill bit is used and the length required to be drilled is quite short. This hole allows the tip of the sensor to come flush with the contour surface. The hole does not have to be precise, as no sealing takes place in the small hole that the user just created.



Center Section

All EFR turbochargers use high-end Ceramic Ball Bearings for Enhanced Turbo Response — Even though BorgWarner has been known as a long-time manufacturer of high end journal bearing turbos, the engineering team developed ceramic ball bearing cartridges for the uncompromising EFR series. EFR bearing cartridges house dual-row ceramic balls in special alloy bearing races to provide substantial friction reduction. The biggest benefits of ball bearings are most clearly realized at low turbo shaft speeds (spool-up region) and they also help improve turbocharger response/boost recovery as found between gear shifts. Once the engine is at full boost, ball bearings offer no advantage in performance – BUT – there are huge performance benefits for getting up to the desired boost level FAST and delivering quick throttle response for on-off-on-off aggressive driving. From a durability standpoint, the EFR cartridge bearing system provides a huge increase in thrust load capacity over conventional systems and requires much less oil supply. From a fuel efficiency standpoint, parasitic loss is reduced at low turbo speed so MPG increases can be realized. Lastly, the EFR bearing system includes the latest in turbo seal technology reducing oil seepage/burning problems often found in aftermarket installations (more on this later!!)

EFR bearing housings have the option for water-cooling. Water cooling is recommended where possible to do so, but not mandatory. If watercooling is not connected, be sure to use clean, high viscosity synthetic oil (15W) and do not repeatedly perform “hot engine shutdowns”.

A properly sized “restrictor” aka oil metering orifice is integrated into the bearing housing so EXTERNAL OIL RESTRICTORS SHOULD NOT BE ADDED TO EFR TURBOS. A -4AN male fitting has been provided on the EFR turbo and a -4AN (¼”) line is recommended. Oil return is tapped to 3/8 NPT as well as 2 bolt flange compatible.  For runs longer than 18″ from an oil feed source, a -6AN male fitting and -6AN line is recommended.



EFR Summary

The BorgWarner EFR turbo is set to become the new world standard for performance turbocharging due to the high-technology feature package, unbeatable performance, and installation convenience. The EFR turbocharger was designed and manufactured with only one purpose in mind: to dominate the street, track, and strip. Multiple different size turbos, optimally matched for the 250-1000hp per turbo segment – and in (4) different turbine housings are the result. The combination of this top-shelf geometry and the Gamma-Ti turbine wheel significantly raises the bar for performance aftermarket turbochargers. Combined with our ball bearing technology, it is the most responsive range or turbos that are available anywhere, at any price. The EFR series covers all applications except the hardcore drag racers. For those hardcore customers, we still offer the highly popular S400SX and S500SX product lines, and will continue to update those turbos during the next year.




Full-Race has worked closely with BorgWarner on application fitment and following the EFR launch, Full-Race EFR turbokits will be available for the following platforms:


  • Subaru Rotated – EFR turbos are compatible with Full-Race’s Subaru twinscroll kit in both Internal OR External WG configurations.
  • Subaru Stock Location – EFR .64 A/R singlescroll Internal WG turbos will be released by Full-Race in configurations that are bolt-in for stock location subarus **requires 3″ vband downpipe**
  • Subaru BRZ / FRS – Twinscroll 7163 recommended


  • Mitsubushi Evo 4G63
  • Mitsubushi Evo X 4B11T


  • Honda K-Series Sidemount (RSX/EP/K-Swap) – Full-Race’s “sidewinder” K series customers have a plethora of EFR turbochargers to choose from in Singlescroll or Twinscroll options and Internal OR External WGs
  • Honda B-Series – EFR Twinscroll External Gate only, fits current Full-Race T4 twinscroll Top mount and T4 twinscroll Bottom mount
  • Honda R18 – EFR complete turbokit
  • Honda 8th gen Civic Si
  • Honda 9th gen Civic Si
  • Honda S2000 – EFR turbos in Internal OR External WG configurations on the brand-new forward mounted twinscroll S2000 manifold


  • Nissan SR20DET – EFR Twinscroll w/ Internal OR External WGs & Singlescroll Internal WG . Fits current Full-Race Twinscroll top mount with or without WG tubes
  • Nissan RB20/25/26/30 – Single turbo and Twin Turbo


  • Toyota 2JZ – Twinscroll w/ Internal OR External WGs Fits current Full-Race Twinscroll top mount with or without WG tubes. **2JZ now available in smaller runner configuration for faster spool/response
  • Toyota 3SGTE – Twinscroll External WG only **Exisitng Twinscroll bottom mount**

Ford EcoBoost

  • Mustang EcoBoost
  • F150 EcoBoost
  • Fiesta ST / Fusion EcoBoost