Yet another new guy 05 OBXT build

Well, I did it. Maybe I made it into the smaller group of posters who come onto this site saying they want a car, or are looking for a car, but then some fade away. Not me! I snagged an ’05 OBXT Unlimited with 150k-ish miles.

 

It has a few problems, of course, as cars of this age tend to do. It looks unmodified, although the brake disks are drilled and slotted. There are some scratches and dings in the paint, but only a bit of surface rust at one point, up high on the roof by the hatch. Decent tread on the tires. Fluids are full, and don’t look exhausted, but I will replace them all by the time I’m done. Interior has some stains, but no rips, and I’m considering learning to knit a sweater with all the pet hair that was included at no additional charge.

 

Problems: cracked windshield, which I found several of in my search for some reason. Rear hatch doesn’t lock. Driver’s door rattles in resonance with the idle, which shakes the car pretty good. I don’t say that it could mix paint, but I bet if I left a pint of cream idling in the driver’s seat after breakfast I’d have butter by lunch. Driver’s seat didn’t adjust fore and aft. And there are engine codes, including misfire on all four cylinders, but it runs decently. I drove it around to get insurance and registration, but I’m not pushing my luck.

 

The first repair I did was the driver’s seat switch. I popped the trim pieces, disconnected the switch and opened it up. Fiddling with tiny contacts, springs and ball bearings is not near the top of my fun-to-do car activities list, but I got it put back together and all the motions work properly now after cleaning contacts with De-Ox-It and sandpaper.

 

I also have in my possession a JDM Spec B 6MT swap kit. Heh heh.

 

So now the fun can begin. My plans are to end up with a car that will outdo my ’08 Audi S4, at least by a little, except in the luxurious accommodation and admiration of passers-by categories. For me, that means tearing down and rebuilding the engine to accommodate a decent amount of power, and replacing all the plumbing to support it. All that power will go to the wheels via the stouter 6MT, and I will remove the OB spacers and make the suspension into a Legacy, maybe lowered a tad, but the goal is not to look terribly modified to non-Subaru fans. I expect to find some looks-like-they-could-be-stock 18” wheels and run lower profile summer tires in season, which is long in Alabama, and have the really-are-stock 17’s for all-season winter.

 

Except for the transmission swap kit, a Cobb APv3, and a Whiteline KTA124 that is en route, I haven’t made enough decision yet to buy anything else. I’m running under budget at the moment, which probably won’t last. I was lazy about getting the garage cleared for action, but that is happening now. Let the fun begin!

*excited Subaru noises*

While I know you have been search long and hard, I expected it to be a little longer. I also didn't expect you to end up with an OBXT even though you included it in your search criteria.

 

Congratulations Subisubisu, welcome to the family! Happy for you and your purchase and I think I speak for most all of us when I say we are excited to see where your build goes.

 

What color is the car?

While I know you have been search long and hard, I expected it to be a little longer. I also didn't expect you to end up with an OBXT even though you included it in your search criteria.

 

Congratulations Subisubisu, welcome to the family! Happy for you and your purchase and I think I speak for most all of us when I say we are excited to see where your build goes.

 

What color is the car?

 

Thank you! I believe it's the Atlantic Blue Pearl. The more I saw about the OBXT, the more I liked it for my purpose, even as I kept my search parameters open. Engine sits a little lower in the engine bay, reportedly. The Spec B 6MT swap kit comes with some of the suspension pieces needed to convert back to Legacy suspension already. With a little extra work on my part as I swap the transmission, those things lower the CG, good for handling. Engine-wise, it's the same as the LGT, and even the Cobb AP doesn't differentiate when I use its car identification feature. And since I'm going for the sleeper thing, OBXT is more sleeper than LGT, to my way of thinking. When this one turned out to have a CEL and was diagnosed with low compression on #4, it lowered the price due to engine work that I was going to do anyway, so I pulled the trigger.

Just for the record, I gather the OBXT is a 5mt ?

 

The engine being lower in the chassis is with all the 05-09's Legacy's.

 

What was the weight of the Audi ? I assume the OBXT is a few lbs lighter ? You want need as much HP.

 

These cars can be great fun with a OEM ej257, upgrade the turbo, fuel pump and injectors and the other normal MODs, Up/Dp, tmic. It really doesn't take much to have a fun DD that will give you years of smiles.

 

Make a list of the things you want and put $$$'s next to each.

Just for the record, I gather the OBXT is a 5mt ?

 

The engine being lower in the chassis is with all the 05-09's Legacy's.

 

What was the weight of the Audi ? I assume the OBXT is a few lbs lighter ? You want need as much HP.

 

These cars can be great fun with a OEM ej257, upgrade the turbo, fuel pump and injectors and the other normal MODs, Up/Dp, tmic. It really doesn't take much to have a fun DD that will give you years of smiles.

 

Make a list of the things you want and put $$$'s next to each.

 

For the record, it is. Auto versions are more plentiful, but my research into the swap convinced me to hold out for the stick shift version. So, it turns out that finding non-corroded turbo+MT examples isn't an everyday occurrence.

 

Looks like the Audi is about 600 lb more luxurious with the Tiptronic.

 

I've plowed ALL the way though the monster 6MT swap thread. I need to do the same due diligence for my turbo and exhaust plumbing options. Early on it looks like UP is not so critical as long as it's catless.

 

I also haven't quite decided on what to do about spring/strut options. Goal includes renewal of as much of the underneath of the car as is practical, for those years of smiles.

Actually, I have plenty of options for most everything and I like being in that situation.

 

Some of the first options I need to evaluate are how to approach the transmission swap. I work slowly, so renting a real-deal lift is not my first preference. However, I need to see how high I need to get the car to drop the transmission out underneath. I may need different stands/jack. Or there is the cherrypicker-out-the-top method that I used on the Audi to get the engine and transmission out as a unit, but I didn't plan on pulling the OBXT engine just yet; goal was to verify the transmission swap first.

I like doing things in steps myself. But if your careful and plan, doing the 6mt and engine shouldn't be to hard.

 

I put my wagon up on the 6 ton HF jackstands using there $70 tranny jack which is about 9" high at it's lowest. With the car about 23" in the air, I could roll the tranny under the car going under the up pipe area.

 

I also have two floor jacks that will lift the car 18", used 4x4 block on the floor jacks to get it higher. I have a Cherry Picker too. Well used to have a race car so I have all kinds of stuff.

I like doing things in steps myself. But if your careful and plan, doing the 6mt and engine shouldn't be to hard.

 

I put my wagon up on the 6 ton HF jackstands using there $70 tranny jack which is about 9" high at it's lowest. With the car about 23" in the air, I could roll the tranny under the car going under the up pipe area.

 

I also have two floor jacks that will lift the car 18", used 4x4 block on the floor jacks to get it higher. I have a Cherry Picker too. Well used to have a race car so I have all kinds of stuff.

 

Thanks for the measurement on how high I need to get the car. Time to get those bigger jack stands I have been coveting. I'm sure I can solve the floor jack problem, and this way I can do it at home like I intended to.

 

I just took a look at the 6MT swap kit. I need to do a tiny bit of rust removal, considering all that there is in the kit; it's in pretty good shape. Paint with some POR15 before it goes on.

 

Now is also the time to consider some parts selections, with default choices that could change. None of it is on hand yet except what came with the Spec B 6MT swap kit and the KTA124.

 

Clutch disk (new STi) - kit vendor recommended replacing

 

Springs and struts (Legacy GT or Spec B with Koni yellow) - because I'm going to be removing the OB spacers and using the Spec B parts from the 6MT swap kit or the Whiteline KTA124 control arms

 

Brake rotors and pads (try what came in the kit, easy change later if needed) - I'm using Hawk Street Performance pads on the Audi and so far, so good

 

Various suspension bushings (Group N hard rubber is leading candidate) - I already have the Whiteline KTA124 and I'll use the bushings that come with it. I want firm but I don't think I want to go full kart racer on the whole car and knock fillings loose.

 

Steering rack (15+ STi is tempting, but maybe I should see what bushing renewal and new tires does for me first)

 

Summer wheels and tires (this space available; so many choices)

 

All the engine compartment and exhaust stuff is down the road a little bit, but I'm gathering my thoughts about that, too.

 

Now looking at this later photo, may be I was able to get the car high enough with normal jack stands.

In thinking ahead about the engine work, I've noticed in the forum some mentions of additions (like catch cans and air oil separators) and deletions (like SAI and TGV and the cat in the up-pipe). I searched for a list of recommended deletions, but didn't turn up anything by the search terms I used. Nothing in this category is on the front page of the free/cheap Legacy mods sticky. Is there such a list?

I don't believe there is a list.

 

My wagon has a AOS but I won't both putting one on my Spec B.

 

I have not gone through the hassle of the TGV delete.

 

The catless up pipe is a must to protect the turbo.

 

These are steer cars, not race cars, so don't spend money for a small gain.

You haven't stated your power goals so anyother recommendations are going to depend on that.

 

My power goal is to be at least a bit quicker than my '08 Audi S4. It's nominally a 340 crank hp car driving all wheels, but about 600 lb heavier than the OBXT if the online information sources are to be believed; I don't have a scale handy. I'm thinking aiming for 350-ish crank hp, with the lighter car, will yield what I'm looking for, without requiring being on the edge of max performance of any of the components in the powertrain if I make good choices.

 

Thanks for the other info. SAI delete isn't as big a deal here as it is in the Audi V8 world? That's a jam-packed, hot engine compartment, and people are usually glad to open up a little space in there when they can, particularly with a system that doesn't contribute to the driving experience and is subject to failure.

 

My power goal is to be at least a bit quicker than my '08 Audi S4. It's nominally a 340 crank hp car driving all wheels, but about 600 lb heavier than the OBXT if the online information sources are to be believed; I don't have a scale handy. I'm thinking aiming for 350-ish crank hp, with the lighter car, will yield what I'm looking for, without requiring being on the edge of max performance of any of the components in the powertrain if I make good choices.

 

 

 

A vf52 with fueling up grades should get you there. It's easy to do what you want. 330AWHP should be all you need, not a big ask.

 

Before you pick a turbo, talk to the Tuner, hopefully you know who that is ?

Thanks for the pointers! I will get to researching.

 

Just back from a quick trip to western NC to look at some waterfalls. I made the wife a little carsick with all the fun I was having with the S4, paddle shifters and all. The OBXT will be perfect for the next time we go there - all the twisty mountain road fun, PLUS a stick shift, PLUS I'll blend right in with all the kayak haulers!

The Teil H-Tech springs have arrived. Today I will do a little surface rust removal from the rear suspension cradle for the Legacy Spec B 6MT swap. It's really very little, but I may as well protect it from rust with some POR15 before mounting it up.

 

I've been researching my wheel options. The Legacy Spec B 6MT includes the brakes to switch over with the hubs, so I need to make sure to clear them. Using the online tire, wheel and offset calculators, it appears that using a 245/45/18 tire on an 8Jx18 wheel would keep almost the same diameter/circumference, which is good for the speedometer calibration. A 45 sidewall ratio isn't the lowest of the low, but it makes the wheel a little less susceptible to damage from potholes and the like than the super-low sidewalls, and is a subtle change from the stock OBXT 225/55/17 look. And it offers a nice big contact patch, good for grip but a little less good for mileage.

 

Maybe I am putting too much emphasis on the speedometer error from different-sized tires, but it doesn't seem like the speedometer is easily recalibrated. I know that the Legacy platform speedometer sensor doesn't live on the transmission, but somewhere on the axle/hub (I'm not sure, obviously). Hmm, I wonder if that will change as part of this 6MT swap?

Koni yellows ordered. OEM wheels in 18x8 with the 5x100 lug pattern don't exist, apparently. The lug pattern seems to be the most limiting. So, looking at aftermarket wheels, most of which seem to have offsets smaller than the stock 48 of the OBXT or 55 of the LGT. An offset of 40 with the 245/45/18 tire I think I want will be essentially the same in diameter and inward toward the suspension, and will poke out 2/3". It looks like it will be tough to do better than that, so I'll just have to see if there is any fender interference, and deal with it if there is. There shouldn't be any from the lining or inward, and the 18" diameter should clear brakes meant for a 17" wheel just fine. The other remaining question is whether the stock OBXT wheels, which I expect to use for all-season (winter in Alabama) tires in the stock size, will clear the Spec B brakes.

Konis arrived. Heard back from one of the tuners I reached out to, but not the other. VF52, Grimmspeed intercooler, Cobb downpipe, 3 port boost control, 1050cc injectors with topfeed conversion will likely do it. I've been looking at lots of components, and ordering some - Group N engine and transmission mounts, water pump and thermostat because why put the engine back together with the old ones?

 

Stopped by a machine shop today that will likely be able to accommodate me to level and square the deck surfaces, and measure and advise me on which size pistons to order. I'm looking at catless uppipes and trying through the computer screen to determine whether the ones that cost $100 more are made of better metal or fit better. Is it worthwhile/advisable to wrap the exhaust pipes with the tape, or with the lace-up jacket?

 

I'm also looking at clutches. I need to stop by the local Subaru dealership and walk into the parts department for the first time to talk about what I might need, since very soon I will not have a stock configuration and will forever be trying to think through how to order things - OBXT to match the car as it was, or LGT Spec B to match suspension, or STi for those things in the drivetrain? Additionally, I've never done a clutch before. I want the right new stuff for when the built engine goes back in, but first up is the 6MT swap and suspension lowering. I just want to verify that I've got the drivetrain mated up correctly, then pull the engine and start all that work. Can I do a short test drive with the OBXT flywheel, for instance? The 6MT supplier recommended replacing the disc, which I will do when it all goes together for keeps, but can I test it with the used one that came with it, without causing damage? These are the things I'm thinking about these days.

maybe read through the technical sections? sll yer questions have been asked/answered many times before. the xenonk tire/wheel thread. the 6mt recipe thread. etc

I work slow, but I'm working.

 

Wheels in the air like she just don't care

 

 

On the way to the 6MT swap. Exhaust, propshaft, rear stabilizer, brakes, rotors and all the springs and struts are removed. Trouble getting the rear diff out or the axles disconnected, so I'm trying to disconnect the hubs, but fasteners are stubborn.

 

 

Heat and Liquid Wrench are enabling progress. I'm glad I invested in a 30 gallon air tank and an air impact wrench. I'm hoping that as I move higher off the ground I will encounter less corrosion. The car really doesn't look all that bad, corrosion-wise, but it's enough to give me trouble. And oh how I wish I had a high enough ceiling to allow a two-post lift!

When removing the rear suspension, I found on both sides that the forward bracket holding the wheel speed sensor cable was secured with wire, not with a bolt. If I saw that on one side, I'd think that someone lost a bolt, but on both sides it looks like a policy. Does anyone have any information to share on the topic?

 

Its definitely supposed to be a bolt.

 

Like that.

Add more zip ties, it's a rite of passage.