Home > Turbochargers > STI/WRX RHF55 Dual Ball Bearing Turbochargers > RHF55 Dual Ball Bearing STI/WRX/LGT/FXT Turbocharger - Stage 2

RHF55 Dual Ball Bearing STI/WRX/LGT/FXT Turbocharger - Stage 2 Avail 05/15/15

Product Description

For the past two years Six Star Speed has been working diligently on a ball bearing direct replacement turbocharger for the current line of RHF55 turbos available on the STI and WRX cars. We had several goals for the project namely high quality and durability relative to OEM ball bearing turbos and features that would make it competitive with high end turbochargers that are not direct bolt on for Subaru applications. Finally we have achieved it and are able to offer the product to the Subaru community.

The Product

Our Patent Pending RHF55 dual ball bearing turbocharger is a retrofit to any OEM IHI RHF55 turbo on the Subaru platform.
The turbochragers replace all current RH55 journal bearing turbos including VF30, VF37, VF39, VF43, VF48, VF49, and VF52.

Staged Power Range

The chart below outlines the features and options available in the series

COMPONENT FEATURE	STAGE 0	STAGE 1	STAGE I.5	STAGE 2	STAGE 3	STAGE 4
60 mm OEM cast compressor wheel	Standard	-	-	-	-	-
60 mm 60 trim billet compressor wheel w/ETT	-	Standard	-	-	-	-
60 mm 64 trim billet compressor wheel w/ETT	-	-	Standard	-	-	-
62 mm 64 trim billet compressor wheel w/ETT	-	-	-	Standard	-	-
65 mm 65 trim billet compressor wheel w/ETT	-	-	-	-	Standard	-
68 mm 64 trim billet compressor wheel w/ETT	-	-	-	-	-	Standard
53 mm 81 trim turbine	Standard	Standard	Standard	Standard	-	-
56 mm 83 trim turbine	Optional	Optional	Optional	Optional	Standard	-
60 mm 84 trim turbine	-	-	-	-	-	Standard
OEM compressor housing 58 mm inlet	Standard	Standard	Standard	Standard	Standard	Standard
Turbine housing port and polish	Optional	Optional	Optional	Optional	Optional	Optional
TurboSmart wastegate actuator upgrade	Optional	Optional	Optional	Optional	Optional	Standard
AVO wastegate actuator upgrade (Twin Scroll)	Optional	Optional	Optional	Optional	-	-

Stage 2 (325-350 WHP)

Compressor Specifications

Compressor Type: Billet machined 7/7 blade configuration with extended tips
Compressor Wheel OD (exducer): 62 mm
Extended tip diameter: 67 mm
Compressor Wheel Inducer: 48 mm
Max Flow Rate: 44 lb/min

Turbine Specifications

Turbine type: Titanium Aluminide 11-blade 81 trim
Turbine Wheel OD: 53 mm (Optional 56 mm 83 trim turbine available)

The Ball bearing cartridge

The design of the cartridge takes cues from the best available tech currently available. Our ball bearing cartridge features:

large diameter full complement full ceramic ball bearings for fast response and durability

Aircraft stainless bearing carrier cartridge

Titanium thrust collar for low rotating mass

Titanium thrust column for reduced heat transfer from the turbine shaft to bearing cartridge.

Titanium Aluminide turbine wheel

OEM form factor bearing housing casting and 100% backward compatibility with all RHF55 turbocharger turbine and compressor housings

The Advantages

Going to a dual ball bearing cartridge has a number of distinct performance advantages over the standard journal bearing RHF55:

500-700 RPM Faster response

Higher boost handling (up to 45 psi)

Greater durability

Greater strength and power handling than OEM IHI RHF5HB ball bearing cartridge such as VF34 and VF36 at a better price.

Added value to your vehicle at a very competitive price

2-year limited warranty

The Difference

We get a lot of questions about how this conversion differs from say a VF34 or VF22. It's a good question and without revealing too much in the way ot trade secrets we will say the following:

20% larger bearing cartridge than VF34/VF22

33% larger bearings than VF34/VF22
20% larger bearings than our own XR Series Ball bearing turbos

Max allowable rotor speed of 200KRPM vs 160KRPM for VF34/VF22

275% higher thrust load capacity than VF34/VF22

100% Compatible with OEM all Subaru RHF55 turbine and compressor housings so no need to change turbine housings or water pipes.

Left to right VF34, 20GXR RHF55 Ball bearing; comparison photos Stage 3 vs Garrett vs VF36

The Turbo
The RHF55 dual ball bearing turbochargers are only available as outright units. We are no longer offering the conversion service. You are however welcomed to send us your RHF55 turbocharger core for a rebate of up to $200 when you purchase a turbo from us.