Subaru EJ20/EJ25 Twin Scroll T4 EWG Turbo Kit

Results

Testimonial:

“the fact is the BW S300SX FMW is a ridiculously good turbo and absolutely unmatched for the price point. I’ve been trying different setups on my STI since I bought it new back in 2006… I’ve used a few of the FP bolt on turbos (regular green, HTA green, red), I used the ATP35R, Garrett 4088R, had a APS header up-pipe (four of them actually because they kept cracking), a Full-Race 1.5 scroll kit, and a Full-Race complete TS kit (what’s on the car now)… The BW S300SX FMW, by far has out performed any of my previous setups… I have spent a lot of time and money trying to make this car a respectable fast daily driver, and had all but given up before Geoff told me about this new BW turbo…This turbo just flat out kicks butt – good boost threshold, makes great power all they way up to my 8000rpms rev limiter, and the boost recover between shifts is just flat out instantaneous… I’m pretty confident that with E85, this turbo will do over 650whp with even more gains in the mid-range – I admittedly was surprise to see the boost threshold of a 35r and the power of a much larger turbo… On the dyno, we were hitting peak boost of ~29psi and then it would taper to ~27psi at redline, on the street it holds 30psi across the board.” Phil Petraca

The following graph compares Phil Petraca’s 2007 Subaru and Full-Race Twin Scroll Turbo Kit equipped withBorgWarner S300SX FMW VS Garrett GT4088R

Dyno:

Subaru Impreza Sti MY12, 2.5 engine, complete Full Race T4 turbokit with intercooler and BW 8375, 1000cc injector, at 21psi on 98oct fuel:

Jager Racing w/ EFR 9174

STi Equipped Subaru Leone by SpeedHunters

Dyno Charts

Subaru STi Specs:
Engine:

• 2.5 Liter, CP pistons 100.5mm, Eagle Rods, ACL main/rod bearings, ARP head studs
• GSC Stage 2 Cams, Gates Timing Belt, TGV Deletes (powdercoated black)
• Full Race Twinscroll EFR IWG turbo kit
• Borg Warner EFR 8374 0.92 a/r
• Full-Race Intake Manifold (rotated) (powdercoated black)
• Full-Race Phenolic Spacers
• Full-Race Charge Pipes
• Full-Race Equal Length Headers
• OEM Gaskets all around

Drivetrain:

• ACT Stage 2 Clutch
• Kartboy Shortshifter
• ACT Lightened Flywheel

Fuel:

• DW 1200cc Top Feed Injectors
• DW300 in-tank pump

Install

Application Notes:

• The OEM Subaru triple layer steel gasket is strongly recommended. There are other less expensive options available, but this is the best because it has a built-in crush ring and is steel so it will not deteriorate. The Subaru part number for the exhaust gaskets is PN # 14038 AA 000. Torque properly to factory specifications.
• Fits OEM oil pan only.
• Some chassis may require a small bend to the aluminum A/C line at firewall (most do not).
• Wrap wire loom as it comes out of firewall with heat wrap and pull with zip ties towards shock tower for additional clearance.
• 2000 degree ceramic coated turbine housing is STRONGLY recommended.
• 2000 degree ceramic coated up pipe, downpipe and lower manifold also recommended.
• Heat wrap recommended and will not void warranty.

Full-Race Rotated STI kits require PS hose modifications. *If you dont want to modify the powersteering hose please look at our Subaru Stock location EFR turbo kits

Full-Race 08+ STI kits requires heat protection around a safely secured ECU plug and the installer should relocate the ABS mechanism higher on the strut tower. This allows the 4″ intake tube to fit through. Pics of stock ABS location (and bracket) interfering with 4″ inlet: