5th Gen LGT - Performance Mods

https://drive.google.com/file/d/0B-RZ_r2vcFjvcl9iLUVCeExLaEhHOUlESzNpWVBDbGg5cGRz/view?usp=docslist_api

Fwiw here are the three charts I have. Stock baseline vs. stage 2 protune (RacerX tmic, catless dp, Perrin Axlebacks, stock fueling&intake)

Then there is the chart after the build granted we did bump up the psi but you can see the "lump" where the the power band increased across the midrange with the cams, valves, springs. Only other change was the RacerX charge pipe and turbo xs 50/50bov. Still on stock fueling&intake

img-150404140725-0001.pdf

Well lookie here.... Pricey, but one less pipe coupler connection than the RacerX.

http://www.hks-power.co.jp/en/product_db/cooling/db/11161

http://www.ebay.com/itm/191831816208?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

As discussed in another thread, it looks like this will not fit USDM cars with a traditional power steering pump. Note that the charge pipe goes OVER the radiator hose and not UNDER like our stock ones, the AVO pipe, and the RacerX pipe. Many non-USDM 5th Gen GTs (and turbo diesels) have the electric steering rack assist (so no pump) like the 6th Gen Legacy and this was designed for them.

Tourqe Solutions finally posted up pics of thier short shift adapter

SSA

http://www.torquesolution.com/wrx-va-short-shifter-p/ts-ss-023.htm

http://www.torquesolution.com/v/vspfiles/photos/TS-SS-023-2.jpg

SSA w/t Delrin bushing

http://www.torquesolution.com/wrx-va-short-shifter-p/ts-ss-023c.htm

http://thumbs2.ebaystatic.com/d/l225/m/mbeqyIYVHkO7RJMb7R5ZDNA.jpg

TL;DR -> From what I understand from at least one expert, 5th Generation Legacy GTs have STI-like intake cams but NOT STI-like exhaust cams. Further, perhaps rather obviously, 5th Generation Legacy GTs would benefit from STI or STI-like exhaust cams.

The FSM gives the following info on the cams:

 

Intake

46.55 — 46.65 mm lobe height

Exhaust

45.85 — 45.95 mm lobe height

Cam base circle diameter:

37.0 mm (1.457 in)

 

So, lift for intake is 9.55~9.65mm while exhaust is 8.85~8.95mm. Commonly available specs for the EJ257 cams is 9.60mm lift for intake vs. 9.8mm for exhaust. So, it seems the '10 LGT motor lost quite a lot of exhaust lift in exchange for the added AVCS.

 

I wonder if dual AVCS EJ257 exhaust cams would fit the E25 heads...

You can certainly use AVCS tweaks to improve spool or low rpm torque. The top-end airflow though... you use the same techniques on either turbo it all comes out the same. You can't make up for the loss in duration and 1mm less lift compared to the old single AVCS or STi D-AVCS unit. The only solution I see for this is using the STi exhaust cams or going aftermarket.

I've tuned both. The 18G spools a tiny bit faster but flows as much air. This motor is so limited by the exhaust cams that the extra compressor flow is useless.

Only the exhaust cam profile is different from other EJ255 / 257 engines. The valve springs are also different from the STi items. '08~ STi cams drop straight in. The drive slot for the oil pump is on the passenger side intake cam only and is also present on later STi cams. We had compared the GRB and BR9 intake cams and they appear identical, and lift is measured as identical.

 

 

Sent from a device using some software.

The stock VF-54 exhaust housing is I think more of a restriction than the manifold, so until you move to something bigger, replacing the manifold is something of a band-aid to a boost control problem you may or may not run into.

 

Just FYI, the stumbling blocks to power in this platform are a little different from the 4th gen that preceded it.

 

1. The turbine housing is a P18, about the same as the earlier VF-40 item in having a roughly 7.5cm2 nozzle area. Where on the 4th gen the housing is a universal Subaru fitment, common to the Impreza platform and with OEM and aftermarket housings available up to 10cm2, the VF-54 flanges are unique. Not even the new WRX shares these flanges. The largest turbine that fits 'nicely' into this housing is a TD05H or maybe a 'small' GT30 wheel, AKA the GT29 wheel. Beyond that the geometry is horrible and leads to poor spool and not much better flow.

 

2. The exhaust cams on the 5th gen LGT motor are 1mm shorter on lift than on all other 2.5 liter turbo Subaru motors. They are more like oldskool EJ205 cams in profile. If you've ever read about oldskool 'hybrid' engines, built from EJ255 blocks and EJ205 heads, and how they fall down at high revs, you know what that means.

 

The above two factors mean that fitting larger compressors, that flow more air than the exhaust flow can cope with, only decreases efficiency and increases both EGBP and EGT. Cramming more air into the engine does not help when there is so much restriction to exhaust flow. I have tried both 18G and 20G compressors on the same car, with the same TD05H hotside, and gotten exactly the same airflow, power and 100~200kph times out of both. For this reason I would advise you to stick with an 18G wheel, to enjoy the same power as the 20G with better response. At this sort of power level you will not see much if any improvement from an aftermarket catback, and using the stock catback will pretty much obviate any boost creep problems.

 

If that's not enough power then go to a combination of larger manifold with non-stock flange, larger exhaust housing, larger turbine, and at least the STi exhaust cam. Since you need to pull the motor to swap the cams, this is point you build the shortblock.

Here is the link for the Process West Verticooler install.

http://legacygt.com/forums/showthread.php/process-west-wrx-verticooler-installation-253808.html?p=5428616#post5428616

Grimmspeed TMIC (for 2015+WRX)

http://legacygt.com/forums/showthread.php/grimmspeed-tmic-5th-gen-gt-254787.html

Looks like maybe another BPV option for us?

http://perrinperformance.com/i-23898974-recirculating-blow-off-valve-for-2015-17-wrx.html

Easy Boost Leak Test for 5th Gen GT. Thanks to brandon.mol.

http://legacygt.com/forums/showthread.php/easy-5th-gen-gt-boost-leak-test-255163.html

Mishimoto STI-08 Radiator install. Yep it fits, but barely.

http://legacygt.com/forums/showthread.php/mishimoto-sti-08-radiator-install-255262.html

thanks for your hard work and info. now if i can just track it all later. haha

i have maybe a no brainer question. you gave me all these tips in my rookie post to the forum. is it realistic to get all these shifter parts together then do them all at once?

and if so any advice about which one to do first? shift bushing, stop, etc?

also do you have to have the sti sts first?

thanks again for all the help

Has anyone done or seen a good write up of installing the Grimmspeed AOS on the 5th gen LGT?

Hi - here's my install of the SG Motorsports AOS. Very similar to the Grimmspeed except the SG has one port in, whereas the Grimmspeed is two ports in. This should helpin ID-ing the pipes etc if you are going down this path.

So for the grimmspeed you just run 2 separate pipes - 1 from the crankcase vent, and 1 from the head vents side by side to the Grimmspeed unit.

(With the SG unit I just tee-ed them in together in part #8 of my post.)

http://forum.liberty.asn.au/viewtopic.php?f=73&t=33993

Cheers.

Hi - here's my install of the SG Motorsports AOS. Very similar to the Grimmspeed except the SG has one port in, whereas the Grimmspeed is two ports in. This should helpin ID-ing the pipes etc if you are going down this path.

 

So for the grimmspeed you just run 2 separate pipes - 1 from the crankcase vent, and 1 from the head vents side by side to the Grimmspeed unit.

(With the SG unit I just tee-ed them in together in part #8 of my post.)

 

http://forum.liberty.asn.au/viewtopic.php?f=73&t=33993

 

Cheers.

Thanks! I ended up going with the IAG AOS after listening to horror stories about the GrimmSpeed causing engine damage.

Just want to put this somewhere to archive it. Thanks to Captain Ned for the info.

VF54 Turbo coolant pipes.

Had the turbo coolant lines replaced today. I'd show you pics of the dead ones, but when the tech went to take them apart they basically collapsed into rusty dust in his hand. I was one good pothole away from a total coolant loss and turbo burn-up. Oi!!

 

My LGT has (had, now traded) 142K miles and 6 VT winters. Anyone here who lives in winter salted-road territory should brave a trip to the dealer to have the turbo coolant lines inspected. The engine you save may be your own. These are the special order parts needed to do the job, and they take about 3-4 weeks to come in:

 

14430AA220          PIPE COMPLETE-TURBO,NO.2        1
14472AA250          HOSE ASSEMBLY-WATER             1
14480AA010          CONNECTOR-TURBOCHARGER  PIPE    1
15194AA100          SCREW-UNION                     2
803912040           GASKET                          4
803912130           GASKET-12.5X17X2                1

Just in case, that last figure is the quantity needed. Got a couple of PMs asking about it, so just making sure

And if you decide to go with the alternative, the Kinugawa kit, you need the extra Subaru spacer. Thanks Shadow_419.

Connector turboo pipe 14480AA010

Turbo 6AN Water Coolant Line Kit M12x1.25 mm TD02 TD03 TD04 banjo type 320-12001-015

AVO Silicone Charge Pipe. Just in case anyone wants to go completely baller.

 

Found this while perusing the Australia Liberty Association forum.

 

http://www.avoturbo.com/catalog/product_info.php?cPath=26&products_id=287&osCsid=ddj05qge201lcd6cn6gtsfevg5

I included the AVO charge pipe and throttle body hose in my stage 2 install at English racing. They declined to install the charge pipe.

"My tech was not super happy with the way this pipe fit. We ended up not installing it. With the engine moving back and forth on that fan shroud it is only a matter of time that it will wear through."

So, this piece might make sense if you free up some room in there.

AVO silicone intake hose for '15+ WRX, '10+ LGT, and '13+ FXT... it's quite pricey though.

http://www.avoturboworld.com/catalog/product_info.php/products_id/422

http://www.avoturboworld.com/catalog/images/Screen%20Shot%202017-02-22%20at%204.18.31%20PM.png

Anyone know if this would fit the Gen 5's and what the difference between this and the Tomioka VF54 turbo upgrade's are and whether the price difference is worth it

http://www.ebay.com.au/itm/Upgrade-Billet-Turbocharger-SUBARU-LEGACY-GT-2010-IHI-RHF5H-VF54-Add-20-HP-/272213234370?hash=item3f612c52c2:g:1tQAAOSw8d9Uyy95

Anyone know if this would fit the Gen 5's and what the difference between this and the Tomioka VF54 turbo upgrade's are and whether the price difference is worth it

http://www.ebay.com.au/itm/Upgrade-Billet-Turbocharger-SUBARU-LEGACY-GT-2010-IHI-RHF5H-VF54-Add-20-HP-/272213234370?hash=item3f612c52c2:g:1tQAAOSw8d9Uyy95

This is a Sticky thread for confirmed parts fitment....NOT QUESTIONS. Please start a new thread to ask your questions. You will get feedback and comments, just not here.

HKB Electronics 0.5v Alternator Booster to aid charging for AGM batteries.

Prothane 16-1610-BL diff bushing insert kit

Great mod for about $25.

I don't know what y'all were complaining about on this install, it took me right about 1 hour and had no issues at all with getting a 17mm box end on the rear diff bolts, even without removing exhaust. Easy install and nice improvement. No increase in NVH from the best I can tell.

Torque values:

- 81 ft/lbs - front diff cradle to subframe

- 37 ft/lbs - front diff cradle to diff

- 56 ft/lbs - rear diff to subframe (not able to torque because of space constraints)

.

Cylinder 4 Coolant Enhancement

So this is new. Ive seen a couple other companies putting some up for sale for wrx/sti's but never listed the 5th gen till now. https://www.iagperformance.com/GDT-Cylinder-4-Chamber-Cooling-System-WRX-STI-p/gdt-1001.htm

Verus Engineering

-Billet Clutch Fork

-Billet Clutch Fork Pivot

-Billet Accelerator Pedal Spacer

https://www.verus-engineering.com/subaru-impreza-wrx-sti-drivetrain

Another option:

IAG Clutch Fork Kit

What’s Included:

(x1) IAG Chromoly Clutch Fork

(x1) IAG Stainless Steel Clutch Pivot Pin

(x1) Spring Release Lever Retainer PN# 30534AA001

(x2) Throw-out Bearing Clips PN# 30539AA000

GoodRidge Stainless Steel Coated Clutch Line

Subaru WRX 2008-2014 / Legacy GT 2007-2012

https://legacygt.com/forums/showpost.php?p=5861136&postcount=575

Thanks bigstrusk!