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Super clean car my friend. This gallery/build actually helped me decide b/w CWP and the ice silver - I went with white on a '20 STI Limited. Couple of questions.
Where did you grab your side mirrors? I'm looking at some of the .jp sites and stateside sites, looking for any recommendations either way.
Second, your DRL bezels look very clean. I'm contemplating going with S4 DRL bezels and adding fogs w/ interior switch - did you come across any '18-20 STIs with that set up, or look into it at all? I'm assuming it's a pretty straight forward ordeal (after reading your DRL wiring write up and watching some subie bros videos), but not having seen anyone else do it makes me wonder if I've missed something in my assumptions. Thanks for the info and clean pics, i'm absolutely stealing some of your mods!
 

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Discussion Starter #22
Super clean car my friend. This gallery/build actually helped me decide b/w CWP and the ice silver - I went with white on a '20 STI Limited. Couple of questions.
Where did you grab your side mirrors? I'm looking at some of the .jp sites and stateside sites, looking for any recommendations either way.
Second, your DRL bezels look very clean. I'm contemplating going with S4 DRL bezels and adding fogs w/ interior switch - did you come across any '18-20 STIs with that set up, or look into it at all? I'm assuming it's a pretty straight forward ordeal (after reading your DRL wiring write up and watching some subie bros videos), but not having seen anyone else do it makes me wonder if I've missed something in my assumptions. Thanks for the info and clean pics, i'm absolutely stealing some of your mods!
Thanks! And congrats on your purchase!

I purchased the mirrors from JapanParts. Since you have the limited model, you would probably want the mirrors that include the blind spot detection (ST91039ST100):

Doing the S4 DRL bezels shouldn't be hard. I wired mine differently than most because people usually either wire them to the headlights on or to accessory power (so they would be on even if the DRL C lights aren't). I was OCD about it and wanted them to always be on at the same time as the DRL C lights. The fog lights should be pretty straight forward as long as you get the OEM switch and wiring.

FastWRX sells a kit, but you probably want other bezels and fog lights:

This thread should give you an idea of what parts are needed:

Good luck! Looking forward to seeing how it turns out.
 
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Discussion Starter #23 (Edited)
I received this rare gem in the mail today.. after searching for over a year. The VF58.. the "holy grail" of Subaru IHI turbos.

Twin scroll, ball bearing, titanium aluminide (TiAl) 9 blade turbine wheel & shaft, 6+6 straight blade compressor wheel, uprated wastegate actuator.. I plan to send it to Giorgio Provinciali @ ASEL for reconditioning with upgraded dual ceramic ball bearings & possibly a billet compressor wheel.

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I guess I have to sell the SwainTech coated Killer B header that I just purchased...
 
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Discussion Starter #25 (Edited)
I thought some may find this comparison interesting. Thanks to @dlheman 's VF56 EJ257 build, this is my primary motivation behind performing the VF58 twin scroll, ball bearing conversion on my '19 STI.. and why Giorgio & his team at Advanced Sports Engineering Lab are currently upgrading my VF58 :D

I extracted this data from the OEM power charts (provided by Subaru/STI) to create a torque curve comparison for various OEM EJ & FA engine/turbo setups.

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Battle of the OEM Twin Scroll Subarus & the USDM STI EJ257.
  • JDM S208: EJ207 VF58 - twin scroll, ball bearing, TiAl
  • JDM STI: EJ207 VF49 - twin scroll, journal bearing
  • JDM WRX S4: FA20DIT MGT2259S - twin scroll, journal bearing
  • JDM Legacy S402: EJ257 VF51 - twin scroll, ball bearing
  • USDM STI: EJ257 VF48 - single scroll, journal bearing, UELH
Unfortunately, I wasn't able to find an OEM power chart for the S209 to include in this comparison. However, peak torque from the larger HKS turbo comes on ~1,000 RPM later than the VF48 equipped EJ257 (~4,700 RPM in the S209 vs ~3,700 RPM with the VF48).

I was able to compile this... a "stage 1" comparison (protune w/ stock hardware) of the S209, S208 & USDM STI (EJ257 w/ VF48). There's a clear winner in terms of area under the curve.. and it's not either engine with the extra 463cc of displacement. As you can see, peak power numbers are great for marketing, bench racing, and bragging rights on forums & social media, but they're often meaningless and fail to depict the actual powerband.

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Area under the curve:
STI S208 S209 Area Under the Curve.jpg


This is why I'm harsh on the S209 and am disappointed that it didn't receive an equal length, twin scroll, ball bearing turbo configuration like the S208. The S208 makes significantly more "area under the curve" (~19%) despite its nearly 0.5L smaller engine. I look forward to being able to add my EJ257 VF58 build to this comparison in the future.

For those interested, illustrations courtesy of my Instagram page @STINickTuned.

And just for laughs while we're on the topic of "horsepower" 🤣

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If you like this kind of technical content & rare Subaru/STI parts, come join our Subaru Motorsports community at Advanced Sports Engineering Lab:

And follow us on Instagram @advancedsportsengineeringlab & @STINickTuned
Or on Facebook: Advanced Sports Engineering Lab
 
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Discussion Starter #27
Why would I go down such an atypical modification path? Many will think that I'm crazy for spending the time & money when I could have just went with an [INSERT Brand] ELH & turbo (Cobb 20G, Dom 1.5XT-R, FP XR Blue, BCP X500, etc.).

My goal is to maximize efficiency, responsiveness and area under the curve. I have no desire for crazy peak power, but rather creating the ultimate OEM-ish EJ257 that Subaru of Japan never made for the US.. the setup that the S209 should have received. I also have an obsession for the OEM+ theme (S-series, Group N, etc.). Previously owning a very responsive, flex fuel tuned, twin scroll FA20DIT also inspired this build. The only somewhat similar documented build that I've seen is the EJ257 + VF56 build by @dlheman (Corsa catback + IHI VF56 twinscroll setup = superior sound).

Advanced Sports Engineering Lab is in the process of rebuilding my VF58 and are one of the only companies in the world that I trust with such a rare turbo. I contacted at least 10 of the most well known turbo re-builders in the US and all said they couldn't and/or wouldn't rebuild it.. I'm not sure they had even heard of this turbo before.

ASEL is rebuilding the turbo with ceramic dual ball bearings, a forged billet aluminum compressor wheel with extended tips (reducing rotational mass while also improving strength & flow), porting the compressor inlet & turbine housing inlet scrolls, ceramic coating the turbine housing, and most importantly, retaining the rare, lightweight TiAL (aka Gamma-Ti) turbine wheel & shaft. Essentially modernizing the turbo with similar features as EFR turbos and the IHI turbos supplied to Ferrari.

I'm hoping that this will make for a virtually zero lag setup when combined with the EJ257's extra displacement, longer stroke, and slight compression bump. The only aftermarket setup that I believe could provide comparable levels of power & responsiveness would likely be a @killerbmotorsport ELH & EFR 6258. I'm just trying to keep up with the FA platform and future FA24DIT STI.. it's a torque monster when combined with a flex fuel tune!

ASEL has been amazing to work with.. sending pictures & videos of the entire process with balancing on their Schenck machine and machining/assembly on the TurboClinic workbench. They clean the parts via sandblasting, ultrasound & solvents.. finishing with a protective coating to prevent rusting. They X-ray, laser & pressure check the components to verify their integrity prior to reusing anything.

The compressor housing is currently in their 5 axis CAD/CNC lab awaiting machining to match the extended tip wing profile of the new billet aluminium compressor wheel. Unfortunately, the lab is busy working on some billet racing short blocks at the moment. ASEL primarily specializes in S-series, RA-R & WRC cars and has a direct relationship to STI. They are a true engineering company.. that happens to also have a strong passion for Subaru Motorsports ;)

I will update once I've received the final pictures, balancing report, etc. Some teasers in the meantime...


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An example of their twin scroll conversion "wake up kit" (not my turbo pictured):

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Discussion Starter #29
You make me wanna send my VF56 to ASEL for optimization and enhancement.

I can't wait to see how your VF58 goes.
I can't either haha I'm waiting for the Cobb Redline CF intake release to decide whether to go with that or the S209 intake. Then I just need to decide what I'm going to do about fueling.. whether or not to upgrade to the Cobb/ID 1050cc injectors & E85 flex fuel kit. The main issue is the strict emissions/visual "smog" inspection that we have in California. All non-OEM modifications/part replacements must be "CARB" certified.. which means that I would likely have to revert the fuel system back to stock and then re-install it every time which would be a huge hassle.

Once everything is ready, I plan to do before & after dynos as well as some road "lag testing" to measure the time that it takes to reach full boost & peak torque in various gears. I would also love to find a local S209 that I could do a dyno comparison with.

Let me know if you decide to send your VF56 to ASEL and I'll see what kind of deal I can get worked out for you ;)
 

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I am sure you will like the TS VF58 on EJ257 and the extra top end above the VF56 is a welcome addition.

Perhaps you can ask ASEL to calibrate your ECU since they have a lot of experience with this turbo.

I myself is currently about to get a new ECU calibration since I am relocating the IAT to the intake manifold using Spec C IAT sensor and re-purposing the rear 02 sensor for wideband. This time by a German tuner. And this time Aquamist will be utilized as part of the tune.
 
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