About a month ago, we learned about an enticing new turbocharger product line from Borg Warner that was due to be released later this year. While we have been developing our Lotus forced induction kits around Garrett turbochargers, the rumors were enough for us to wait and see what Borg Warner was up to.
The rumors turned out to be true and now Borg Warner recently gave the green light for their distributors to go public with information about the revolutionary new turbochargers they are releasing.  The Borg Warner EFR turbochargers are a very exciting new addition to the afermarket turbocharger industry. These turbochargers are the result of a ground-up redesign with automotive aftermarket in mind.


Photo courtesy of: cosworthusa.com

Here are some of the features:

Low Inertia Turbine Wheel
Gamma-Ti turbine wheel cuts turbine inertia by roughly 50% dramatically improving turbo response.  Turbine sizes range from 55 to 80mm in exducer diameter

Heat Resistant Turbine Housings
Investment cast stainless steel turbine housings improve durability and offer an offer extremely smooth internal flow channel.  Turbine housings have thin walls to reduce weight and thermal inertia.

High Turbine Efficiency
Superback” and “Fullback” back-disk shapes offer very high efficiencies. The Superback shape adds a curved profile to the backdisk and has the effect of lowering centrifugal stress and permitting higher rotational speeds.

Enhanced Turbo Response
EFR turbochargers use a dual-row ball bearing cartridge with ceramic balls and metal cage.  This bearing system provides substantial friction reduction at low turbo speeds and in the process helps improve turbo response.  Metal cage improved the durability of the ball bearing assembly

Flexible Compressor Cover
The EFR turbo “large” cover has a dual-machined outlet, both for a hose connection and a v-band connection.

Simplified Installation
Integrated compressor recirculation valve (CRV) to help avoid compressor surge and backflow during a throttle lift event.  This feature helps to simplify the installation task and lowers overall system install cost

Forged Milled Compressor Wheels (FMW)
EFR turbos contain wheels that are fully milled from forged aluminum, commonly known as “billet”.  Cut from custom forgings, their strength exceeds that which is available from typical bar-stock and also exceeds the material properties of an aluminum casting

Sensor mounting convenience
Speed sensor mounting provisions are also supplied on every compressor cover.  Speed sensors are sold separately.

Boost Control Solenoid Valve (BCSV)
A boost control solenoid valve (BCSV) is included with every EFR turbo.

High Flow Wastegates
Purpose designed large wastegate ports give the wastegated EFR turbos the capability of handling the flow requirements of high performance applications

Ease of Orientation
Turbo orientation flexibility is facilitated by the wastegate bracket to bearing housing mounting arrangement.

Adjustable Wastegate
The fabrication and installation task is simplified with wastegated EFR models that feature adjustable wastegates available in three different canister sizes.

More information: http://www.cosworthusa.com/news/article.asp?idpage=57

Here at Radium Engineering, we are very excited about this new approach to the turbocharger and look forward to using them in future applications. Due to the increased size of EFR turbo's we will not be using them on our Lotus Elise/Exige turbo kits.