Subaru EJ20/EJ25 Stock Location EFR T25/V-Band IWG Turbo Kit

Results

Video:

Yimisport / Jager Racing Subaru STi – Jager Racing has proven the effectiveness of this kit with their dominating Subaru STi. Multiple back-to-back time attack championships and track records, solidified their title as the fastest street-tire time attack car in the USA, for 2013 and 2014, using our stock location kit, 2 bolt lower header and EFR7163 turbo:

Customer Testimonial:

Previously, Redline Time Attack’s 2013 Street Class rulebook limited turbos to 50mm inducer – so when Yimisport’s 100% stock longblock 06 Subaru STI needed to upgrade their VF39 the BorgWarner EFR6258 was an obvious choice – one week later they nabbed Street AWD and Overall Street Class Championship! This year the 2014 rulebook allows for a larger turbo – so they run the EFR7163 vband in the same stock location

Customer: ” I want my car to make more power and spool faster than the stock turbo”
Yimisport: “Sorry, but that would require defying the laws of physics. More power means a bigger turbo, and that means at least a small hit to spool”

Borg Warner’s EFR series turbo have now made that statement obsolete. Just switched out our Redline Time Attack Street Class 06 STI from the stock VF39 to an EFR 6258. Added a reverse intake manifold FMIC, the turbo and retuned. Bone stock unopened long block. E85 fuel. Results speak for themselves. 2013 Street AWD and Overall Street Class Championship specs:

• Bone stock (never opened) longblock 60K miles
• Reversed intake manifold FMIC w/ TGV deletes and 3″ CAI
• Full-Race stock location up pipe, lower manifold and catless turboback exhaust
• E85 Fuel
• Boost level: 24.5 psi on both in the midrange. EFR6258 tapers to about 20 psi. VF39 tapered to about 13.5 psi *note VF39 used stock TMIC

Super Street Magazine installed our stock location EFR turbo kit:

Dyno Graphs:

2006 WRX, stock EJ25 from VEX Performance

“Here are the results we’ve achieved with the EFR setup on a 2006 WRX. STOCK engine, Full Race ELH headers, STOCK STi TMIC, Aquamist water meth system. We’re acheiving full boost around 3300rpm and achieving around 380ft.lbs peak torque! More power across the board compared to stock. This is truly a no compromise upgrade for these cars.”

2005 STI: EFR6758 vs Stock VF39 from CAM Tuning

“Both tunes at 25 psi. Car was tuned in 2012 on stock turbo and was back today with new turbo setup. Gave up very little down low for a 100hp gain up top.”

EFR6258, stock 2.0L 2005 WRX EJ205, 93octane pump gas from Evans-Tuning, 335whp

 

EFR6758, stock 2.0L 2005 WRX EJ205, 93octane pump gas from Evans-Tuning, 378whp

 

Evans-Tuning.com 2.0L 2005 WRX EFR6258 vs EFR6758 comparison:

Comments from the tuner: “These graphs are from (2) 2005 WRXs I tuned using your stock location EFR kits, same setups other than the turbo. Both are stock engines on 93 octane, and boost was set at 22 psi, from having the OEM map sensor in place still. They are both MAF based tunes.

The 335 whp graph is the 6258, the 378 whp graph is the 6758. Spool is nearly identical between them. I think the 6758 is the way to go on the Subaru’s for 400 whp street turbo. I am going to suggest this kit with the 6758 to a few of my STI customers, I am sure they will go for it after seeing these results. All of the stock location turbos I have worked with spool like absolute crap. For reference i am also attaching the customer with the 6758 turbo with a overlay to his previous blouch dominator 2.5 turbo. Its night and day difference. Thanks!

2008 STi, stock EJ25 longblock from Yimisport

Pump and E85:

Pump and E85 compared with a typical Stage 2 08+ STI:

 

2006 STi, stock EJ25 longblock, from CamTuning

EFR 7163 (red) vs GT3076R (blue) vs S200SX 7670 T3 (green):

 

2005 STi, stock EJ25 longblock, EFR6758 stock location