Yet another new guy 05 OBXT build

[subisubisu]

Past time for an update, but I don't have as much progress to report as I'd like.

 

My former military aviation machinist friend came over and used my tools to make it look easy to remove the flywheel bolts by hand. After that, I was able to install the new ACT clutch, yellow and pretty, with the STi flywheel.

 

At that point it was time to put the transmission in, but after trying it myself, I elected to wait until I had help. And I ended up waiting quite a while, but at last it was mated to the engine. At that point I got ahead of myself and installed the starter before determining that (of course) I needed to bleed the clutch, so off came the starter and I detached the slave cylinder to get it physically above the master so the air could be ejected. With that done, the clutch would still go to the floor, and that's when I really learned the difference between pull clutches (6MT) and push clutches (5MT) - I hadn't seated the release (throwout) bearing when the transmission was mated to the engine. I was able to do that by leaning on the release lever. By the way, all this stuff is not much fun when you're not a tall guy and the car is on jack stands and you're having to reach down to the top of the transmission to detach and reattach the slave cylinder or fiddle with the release lever. But it had to be done, and now it is, and I have an operating clutch and it appears that I can select each of the gears, including reverse with its lockout feature.

 

I thought things would go fast now, so I torqued down everything so far (reinstalling the starter once I was confident the clutch was holding pressure) and installed the driveshaft, which appears to fit perfectly (as it should, the kit came from one car) and I thought I'd wind up the evening by placing the downpipe on the turbo and leaving the heat shield installation for tomorrow. Removing it was no fun, and I figured installing it would be a real bear.

 

HOWEVER, I find that the OBXT downpipe is not going to fit as-is with the new-to-the-car 6MT. There is a bracket that interferes with the transmission that doesn't let me line up the flange to get the downpipe on the 3 studs. I must have overlooked this in that long 6MT swap thread. I guess I will need to be ordering a new downpipe sooner rather than later so that I can do the test drive - it was always in the plan, but I was trying to put off the performance upgrades until after I had verified the 6MT installation and pulled the engine for the teardown and rebuild. Oh well, have a plan, but be ready to re-plan.

[Max Capacity]

I could be wrong but I thought the 2005-2009 Down pipe for a MT car are all the same.

 

I don't think there is a difference between 5mt and 6mt.

 

I know the support bracket on a DP for a 5eat is located in a different spot. But the DP is the same shape. (?) as far as i know.

 

Did you make sure the divider plate is not hitting the waste gate ?

[subisubisu]

Well, maybe better late than never. I checked opposedforces and there are several part numbers for the "center pipe". My OBXT was manufactured in mid-2004, and should have one part number; there are two others for OBXTs built later on.

 

And of course no OBXT was built at the factory with the 6MT, so for those parts I am consulting the 2008 Legacy GT Spec B drawings, which shows another part number.

 

Going to subaruparts.com and telling it that I have an '08 Spec B, it tells me that the OBXT part number will not fit, and points me to the same part number that opposedforces' drawing says would be present.

 

Of course the kit I bought was from a JDM car, so I am crossing my fingers that a US 2008 Spec B will be similar enough in this respect.

 

I need to keep this in mind when shopping for a performance downpipe.

[Max Capacity]

Have you called someone at like...Rallysport or importimageracing or even Grimmspeed to see why the Legacy GT dp won't fit into your OBXT....which is basically the same chassis.

 

There are a number of guys on here with a Dp in there OBXT's, even some with 6mt's.

 

Found this,

Invidia Catless Divorced Downpipe Subaru WRX 2008-2014 / STI 2008-2020 / Legacy GT / Outback XT MT 2005-2009

HS08SW1DPN

 

selected a Spec B and got this,

Cobb Catted Downpipe WRX 2008-2014 / STI 2008-2020 / Forester XT 2009-2013 / Legacy GT / Outback XT 2005-2009

524210

 

here's the site, https://www.importimageracing.com/collections/exhausts?productFilter=Vehicle_Make%3ASubaru%3B%3BVehicle_Model%3ALegacy%3B%3BVehicle_Trim%3A2.5GT%20Spec.B%20Sedan

[Max Capacity]

Also, when I bought the used Dp for my Spec B I had to cut the divorce plate back even though the Dp came from a members car on here.

[subisubisu]

Thank you for the info! I haven't called anyone yet, but I will sure to lay out the configuration my car is in when I do.

 

It's my first experience modifying a car, and while it's an experience I wanted, I am learning that it's a challenge to keep up with the various parts and their relationships with other parts and the basic car: It's an OBXT, except that I put a Spec B 6MT in it, with an ACT clutch and an STi flywheel, that drives a Spec B drivetrain out to the hubs, with Spec B aluminum suspension members, except that I have Whiteline camber and toe arms in back and the roll center kit up front, oh and it's lowered because I removed the spacers. And the Koni cut-a-strut mod with Tein lowering springs. And Audi exhaust hangers (surprisingly 1/3 the cost of Subaru ones). And that's before any engine work. At this point I think I'll just do a compression test while the starter is connected to turn the engine to see what I have to start with, and then start the engine pull so I can get the rebuild rolling. I'll have plenty of time to figure out the downpipe compatibility question then.

Edited November 4, 2020 by subisubisu

[subisubisu]

Before starting the engine pull, I did a compression test. It was on a cold engine, since it hasn't run since June and without being able to install the downpipe I wasn't going to run it now; if I could run it, I'd drive it to confirm the transmission install.

 

When I bought it, it was acknowledged to have a problem in cylinder 4. The little bit I drove it I experienced some misfires, and I did NOT run it hard.

 

So, the compression results:

 

Cyl 1: 120 psi

Cyl 2: 110 psi

Cyl 3: 120 psi

Cyl 4: 20 psi

 

Well, THERE's your problem! After I get the engine out, I will attempt a leakdown test to further diagnose, but the plan has always been to tear it down completely. The question at this point is, do I need a new short block?

[Max Capacity]

Once the left head is off, you'll know for sure. Either cracked ring land or bad valves.

[subisubisu]

Once the left head is off, you'll know for sure. Either cracked ring land or bad valves.

 

So on the leakdown I should either hear air escaping the sump (drained the oil, so no gurgling) or escaping the exhaust or intake manifolds to tell me which one to expect to see when I pull the head off.

 

I've got the engine about half undressed now - alternator and power steering pump off, air intake off, coolant disconnections done except for the heater core. It will be out this week.

[Max Capacity]

So on the leakdown I should either hear air escaping the sump (drained the oil, so no gurgling) or escaping the exhaust or intake manifolds to tell me which one to expect to see when I pull the head off.

 

I've got the engine about half undressed now - alternator and power steering pump off, air intake off, coolant disconnections done except for the heater core. It will be out this week.

 

Yes, think it through, it will make sense.

[subisubisu]

Leakdown points to exhaust valve trouble. #4 would not hold pressure, whereas #2 next door had less than 20% leakage. New to me test gauge, didn't spend a ton of time trying to dial it in exactly. Rotating through the cycle, air never stopped going through the exhaust, while intake started and stopped noticeably and the sump never sounded off.

 

Then the inspection camera showed only some VERY light scoring on the #4 cylinder wall, basically normal wear, it appears. Couldn't see anything obvious about the valves, which were still in place and moving. I will know more when the heads come off.

 

At least at this point it's not looking like YNANSB.

[subisubisu]

One of these things is not like the others...

 

 

That's the intake valves on the left, exhaust on the right, for the number 4 cylinder. The oddly-colored exhaust valve is the rear-most when mounted in the car.

Edited December 10, 2020 by subisubisu

[Max Capacity]

Looks like the lower valves in the picture are seating deeper then the top two...?

 

That one exhaust valve looks burnt ?

[subisubisu]

Burnt is the opinion of a more-experienced local friend. However, the heads and case halves are at the machine shop now. Time to turn my attention to cleaning the parts that I've pulled off and deleting the TGV and installing the new fuel pump and other sundry tasks.

[subisubisu]

It will be a little while before the pieces come back from the machine shop and I can start reassembly. Today I locked down the turbo - thanks JMP! - and that's about it for the performance parts external to the engine. Everything else is either on hand or ordered.

 

One of the things ordered is an OEM engine seal and gasket set. I thought about hoses, too, but I don't see a similar OEM set, and even aftermarket hose sets seem thin on the ground. I only broke one hose that I know of taking them off - a breather hose in the middle of the top of the crankcase, toward the rear - but it might be nice to renew some of the others. Am I missing something?

 

ETA - Maybe I should clarify that I do read this and other forums, and I'm aware of previous threads about efforts to do a group buy to encourage a manufacturer to create a kit for the Gen 4 LGT/OBXT, the pricey kit available from Britain and I think one more aftermarket option that seems to be still around. What I'm not seeing is an OEM kit; I guess individual parts are available, but there are quite a few pieces to look up. And OEM is apparently rubber, and some of the aftermarket silicone hoses might be preferable. One of many things I don't know is if there are STi kits that are known by some to be pretty much applicable to the Gen 4 LGT/OBXT. I know our engines are very close in terms of the block and heads, but the external plumbing might or might not be the same.

Edited December 12, 2020 by subisubisu

[Max Capacity]

https://legacygt.com/forums/member.php?u=34081

 

or

 

find him in post 165 here, https://legacygt.com/forums/showthread.php/oem-online-subaru-parts-vendors-list-42243p5.html

 

May be contact Benny and see what he can do for you on heater hoses and others you think you want.

 

Have you checked your local dealers site to see if they sell parts at a discount ?

[subisubisu]

Thanks, Max! Good to have references. I have some time coming up to go through all the parts I pulled off during and after the engine pull to get down to the block and heads that are now at the machine shop. I'll clean them up and inspect them, and make a determination on which ones are serviceable, and see about replacing the others.

 

My local dealership will price match if I show them the price on my phone. If I don't insist, they don't offer.

[Max Capacity]

Keep working with them, get to know the guy's. When we purchased are 2016 Outback, in trying for a better deal, I mentioned I've spent a lot in their parts dept and the guys know me. He went away and came back and said, boy did they speak highly of you, we can take more money off.

 

I have been able to build long term relationships with a body shop, trusted mechanic, machine shop and tranny shop. The payback is priceless.

[subisubisu]

Things have been slow over the winter, but lately it's been picking back up.

 

Even down here in the south it gets cold in an unheated garage, so I haven't been fooling around with some of the different chores while waiting for my turn to come around at the machine shop. But last weekend I did pull the fuel pump from its well in the tank and get it separated from the bucket, only to find that I was not comfortable with putting the AEM 50-1000 in - it doesn't connect in the same way as the OEM part, and it's a little longer. AEM also has the 50-1215 that looks the same as OEM and it's on a UPS truck delayed by the stormy weather we had in the middle of the week instead of on the bench ready to go in today.

 

I'm also working on the TGV delete process with the STi-pulled top-feed parts I've procured. Flaps, rods and motors are off and it's time to remove the center wall from the tunnels. I have M10 set screws on the way, since local big-box home improvement stores are apparently not big on metrics. I could have gone SAE, since I have to tap threads anyway, but I already have metric taps and not SAE ones. I can make progress here this weekend, after my coffee and running over the yard with the mower to bag up the dead remains of last year's growth and a few weeds.

 

My turn has finally come around at the machine shop. After cleaning things up, the crankshaft was polished and turned out to measure STD/STD. The bores are slightly out of round, so 99.75mm Mahle forged pistons are inbound and the cylinders will be bored to match. The Manley H-Tuff rods came in this week. The heads hold pressure, and as of now the valves all look OK; apparently there was some trash preventing exhaust valve closure in #4 and creating the lack of compression. I've already given them the new valve springs and retainers, so a valve job is either underway or starting soon.

 

This machine shop doesn't have a torque plate for the EJ25, and I'm seeing differing opinions on the necessity of using one for a street engine. I could get one for them to use, but I'm undecided, not least because I won't be there to see how they use it. Apparently the best practice is to bolt the case halves together to torque spec and install the head on the other side, using the torque plate on the side being bored. Just attaching a torque plate to a case half won't impart all the stresses present in a fully-assembled engine. How many of you who have had cylinders overbored or honed used a torque plate in the process?

 

The Manley rods came with a caution to check for rod-to-block clearance before fully assembling the engine. As it happens I had recently watched an EJ25 build video where the builder relieved some material from the case for just this reason, although he did it to prevent the possibility of a problem, not because he had diagnosed a problem. I don't see much mention of problems of this nature when searching forums; one time I did it was Eagle rods, not Manley. Is this something that happens often and is just part of the process of building an engine with non-OEM parts?

 

Anyway, glad that spring is here and after last year being the year of the tear-down, finally getting 2021 started on the build-up path.

Edited March 20, 2021 by subisubisu

[LGTmakes3]

Sent a PM

[subisubisu]

Thanks, replied.

[Max Capacity]

Is there a reason you didn't go with the AEM340 pump ? I have a AEM320 and its a direct bolt in...the 340 replaces the 320 from what I understand.

[subisubisu]

Is there a reason you didn't go with the AEM340 pump ? I have a AEM320 and its a direct bolt in...the 340 replaces the 320 from what I understand.

 

Hi Max, it IS a 340, but that is more of a class of pumps designation as I understand it. 340 is the flow rate in liters per hour. The other is a more particular part number. The 50-1000 is a "universal fit" that may require modification for any individual application. The 50-1215 APPEARS from the online photos to have the clips built in to make it just like the presumably original part I removed, and Flatirons Tuning says that is the one for the 2005-09 Legacy GT. UPS is supposed to drop it on my porch on Monday. Both are AEM 340 pumps.

 

ETA: Here are the pumps: top to bottom, the one I pulled from the car, then the 50-1215, and lastly the 50-1000 "universal fit", which can be observed to be longer and lacking the clips to fasten it to the enclosure that sits in the bucket. I declined to make any mods to the enclosure to accommodate the universal fit model, preferring one that is a form and fit replacement.

 

Edited March 23, 2021 by subisubisu
adapic

[subisubisu]

And the new fuel pump is now in the bucket, and the bucket is in the fuel tank. It will be a while before I have an engine in the car to check it out, though.

 

And I am not at this point doing the parallel wiring mod such as described here: https://legacygt.com/forums/showthread.php/upgrading-your-fuel-pump-wiring-4th-gen-213570.html

 

I don't know right now whether I have a problem, and I have disturbed so many systems in this car that I am dreading the start-up process.

[TMBLKDG]

Things have been slow over the winter, but lately it's been picking back up.

 

...

This machine shop doesn't have a torque plate for the EJ25, and I'm seeing differing opinions on the necessity of using one for a street engine. I could get one for them to use, but I'm undecided, not least because I won't be there to see how they use it. Apparently the best practice is to bolt the case halves together to torque spec and install the head on the other side, using the torque plate on the side being bored. Just attaching a torque plate to a case half won't impart all the stresses present in a fully-assembled engine. How many of you who have had cylinders overbored or honed used a torque plate in the process?

...

 

Anyway, glad that spring is here and after last year being the year of the tear-down, finally getting 2021 started on the build-up path.

 

 

I sure can understand about slow progress. I've been away from here for over a year as my project has sat untouched all that time. Other priorities have come up, but I'm almost to the point where I can get back to it and get it finished.

 

To address the part of your post I quoted above - I've never machined or had machined a Subaru engine, but I have done other (domestic) brands and one Honda b-series as I used to work in a machine shop.

 

Those experiences lead me to believe that torque-plate honing is the ONLY way to go. Unless there is something special about the Subaru engine design, it will make a noticeable difference to the way the rings seal up and thus the performance and longevity of the final product.

 

Torque plates aren't terribly expensive - in the $200 range and you could always re-sell when you're done with it.

 

Anyway, that's just the thoughts from a guy who spent a year in a machine shop building domestic V8s and one turbo'd Honda, so take it for what it's worth. If it was my engine, I'd make the torque plate happen.