08 SpecB top end rebuild analysis

I am having my top end rebuilt on my 08 spec b with 109k. The car is completely stock. I did just have new stock injectors put in. I have kept up with service intervals.

 

While the motor is out of the car at the shop I have the chance to save on some labor. My immediate thought is to have the clutch done (probably OEM STI flywheel and clutch kit). with 109k it is only a matter of time and I think it is a lot of labor as a single job.

 

My second thought is to replace the turbo with vf52 or bnr 16g. I am not the original owner and seems to me that there may be a correlation between valve replacement and turbo replacement. Shop will check the turbo for shaft play but would hate to have it go after the top end was rebuilt.

 

My budget for the additional parts would be 1700. Do you think this is the best course of action or would the money be better spent elsewhere? I think the clutch is probably a no brainer but not sure about the turbo.

If you are dumping all this money to rebuild the top end, then you NEED to change the turbo now. With that many miles, it could literally go at any minute. If the 08s have banjo bolts, remove the screens on those. Clutch, yes 100% 1700 is not enough if you want a clutch/install, plus, turbo/install/tune/fuel pump. $2000 might get you there. If you can afford it,the VF52 is a great turbo with minimal difference in lag, and decent top end.

OP, here's a great VF-52 -

 

http://legacygt.com/forums/showthread.php/fs-me-vf52-turbo-228099.html

 

And a more used, but slightly less $$ option:

 

http://legacygt.com/forums/showthread.php/vf52-maddad-v2-header-swaintech-exedy-oem-clutch-228116.html

 

52s are less prone to failure, so that's a plus, and on stock fueling, you can get close to 300hp. You've just recently replaced your injectors, so, it's probably in your best interest to keep them for awhile.

 

While you're in that second post, check out his clutch setup, too. Might be a good $$-saving replacement. Heck, I bet he'd offer you a deal on the two of them, though the 52 is at a fantastic price.

 

While you're doing all this, it would be wise to replace your turbo inlet as well.

 

When you say "top end" rebuild -- do you mean your heads are coming off, too? If so, estimate an additional $400 for headwork at a machine shop, plus new HGs @~$100.

 

If you don't have an AP or a tune, you should really get on that. Fresh parts and a new tune should carry you at least 50k miles trouble-free.

The heads are coming off later this week and being sent to the machine shop. Valves cut and seated ect.

 

I will do the VF52 then.. Are there any additional supporting parts that I need specific to the VF52 or do I use all the 08 spec B parts and only the turbo is different.

 

Will I be ok on a stock tune and stock downpipe for a bit. My IDC with new injectors just before the rebuild was only like 38% at WOT so seems like injectors have plenty of room. I don't want to slap the turbo and cause knock though.

 

280 - 300 hp is perfect for me, I am not a good enough driver to handle above that anyway lol.

 

Thanks for the input.

The heads are coming off later this week and being sent to the machine shop. Valves cut and seated ect.

 

I will do the VF52 then.. Are there any additional supporting parts that I need specific to the VF52 or do I use all the 08 spec B parts and only the turbo is different.

 

Will I be ok on a stock tune and stock downpipe for a bit. My IDC with new injectors just before the rebuild was only like 38% at WOT so seems like injectors have plenty of room. I don't want to slap the turbo and cause knock though.

 

280 - 300 hp is perfect for me, I am not a good enough driver to handle above that anyway lol.

 

Thanks for the input.

 

Your stock fuel setup should be fine for now. In the future, you should get a new fuel pump and consider bigger injectors.

 

You WILL need a tune. Get an AccessPort if you don't have one already, or get a good open-source tune. It's money well-spent, and is probably the best mod in terms of performance AND safety/longevity/reliability.

 

While you can probably get away with using a stock DP, there are plenty of cost-effective (read: cheap) options. A new CNT catless DP can be had for about $200.

 

Have you removed the air pumps and done the TGV deletes yet? If not, you should do those. Pretty easy to do if you have access to a die grinder and lots of air. Once you take the manifold off, it's pretty self-explanatory.

 

Your stock motor is only really good for ~350whp, max. Sitting at 280-300 is prime real estate.

Ok cool, The nearest tuner from me is probably 1.5 hrs away. If I get all of this installed do I have to flat bed the car there or can I just drive it easy to the tuner.

 

I have a tactrix so I guess an etune would also be an option. I only use the tactrix for logging and learning what all the parameters mean and how they are calculated. Not good enough to tune yet.

Ok cool, The nearest tuner from me is probably 1.5 hrs away. If I get all of this installed do I have to flat bed the car there or can I just drive it easy to the tuner.

 

I have a tactrix so I guess an etune would also be an option. I only use the tactrix for logging and learning what all the parameters mean and how they are calculated. Not good enough to tune yet.

 

That's fine. Sounds like you'd be a good candidate for Cyro Infamous here, then. click on Vendors at the top -- They're both listed and reputable. Go with whomever you like best. I recommend Mike, (msprank) from Infamous, as I've dealt with him in the past, and want to see his business succeed.

I would never, ever have a motor out of a 2.5 Subie turbo and not put forged pistons in it. At that mileage, and if you're going to crank up the boost, you're just asking for the piston ringlands to come apart and destroy EVERYTHING!

 

You can get your turbo rebuilt for around $420. Or get a 16G or 18G. The VF52 is good too but you'll also need a tune.

 

If it were me, for that budget, I'd put forged pistons in (cylinders can get a very light hone if they measure out OK), heads rebuilt stock, get a catless UP and remove that EGT probe (do the simple resistor mod to cancel the tune), get the VF40 rebuilt, clutch, and ensure all the banjo bolt screens are removed. Other than that put it back together and you might be away for $1700

 

Getting a bunch of other crap done, and still having the stock pistons (which could be ready to blow up at any time)..... to me, is madness.

I checked on the VF40 @ http://www.subaruonlineparts.com/ price and that is almost as much as the VF52!

 

Will the MPG be similar with the VF52 and stock fueling? Don't mind if it drops to 20 - 22 MPG. Stock turbo and fueling seems to average about 22-25 ish.

Yeah, the difference is you need a tune with the VF52. So add $500-1000 depending on how you do it. You could rebuild your VF40 for $420 and be done with it, not need a tune at all.

 

If you get the VF52, you might as well gut your TGVs b/c then the TGV codes can be tuned out also.

 

Mileage should be better with a bigger turbo breathing easier, at cruising speeds, with a good tune (especially if you get an eco tune that you can swap in for long trips etc).

 

You ought to focus for a second on the pistons, seriously.

I would never, ever have a motor out of a 2.5 Subie turbo and not put forged pistons in it. At that mileage, and if you're going to crank up the boost, you're just asking for the piston ringlands to come apart and destroy EVERYTHING!

 

You can get your turbo rebuilt for around $420. Or get a 16G or 18G. The VF52 is good too but you'll also need a tune.

 

If it were me, for that budget, I'd put forged pistons in (cylinders can get a very light hone if they measure out OK), heads rebuilt stock, get a catless UP and remove that EGT probe (do the simple resistor mod to cancel the tune), get the VF40 rebuilt, clutch, and ensure all the banjo bolt screens are removed. Other than that put it back together and you might be away for $1700

 

Getting a bunch of other crap done, and still having the stock pistons (which could be ready to blow up at any time)..... to me, is madness.

 

Do I have to be concerned with forged pistons on a DD? I was under the impression that the stock piston clearances were better suited for the sub 300whp DD engine build. But this is only what I have read.

Do I have to be concerned with forged pistons on a DD? I was under the impression that the stock piston clearances were better suited for the sub 300whp DD engine build. But this is only what I have read.

 

With a good tune, you should be just fine on the stock pistons. Forged internals on a DD is a bit overkill. Fun, and awesome, but overkill.

...get a catless UP and remove that EGT probe (do the simple resistor mod to cancel the tune)...

 

08 already has a catless up and the 2 probes are in the down pipe and end pipe; don't delete them.

Not that this proves anything about future reliability but they will do a leak down test before hand just to be sure the bottom end is good.

 

I will probably go with an Infamous eTune. I have the tactrix setup and RomRaider monitoring. I don't really care so much about the dyno numbers.

On the VF52 swap are the stock oil lines pretty stout or should they be replaced?

On the VF52 swap are the stock oil lines pretty stout or should they be replaced?

 

Your stock lines should be fine.

Your stock lines should be fine.

 

With the OEM STI clutch kit. Is there any year that is a better clutch build or are they all the same from 05+

With the OEM STI clutch kit. Is there any year that is a better clutch build or are they all the same from 05+

 

Same.

Well, if you can find it, you'll want a Single Mass Flywheel. Is the '08's still a DMFW?

Well, if you can find it, you'll want a Single Mass Flywheel. Is the '08's still a DMFW?

 

I am gonna order the matching STI flywheel too

Well, if you can find it, you'll want a Single Mass Flywheel. Is the '08's still a DMFW?

 

08 is SMFW, no need to purchase an STi flywheel; just resurface the one you have. I think the difference in weight is only 4 lbs.

Thanks for all the feedback. My final configuration is as follows.

 

New OEM fuel injectors (already completed)

Leakdown test on bottom end

Rebuild top end (stock configuration)

VF52 turbo replacement

CNT racing catted downpipe -

OEM STI clutch kit and flywheel

Cryo performance stage 3 (stock fueling) e-Tune.

 

The Cryo e-tune seems like a great value.

:)Well the work is underway! It should be done by the end of next week.

They did the full leak down and I was losing 18+ psi out of the exhaust valves, the bottom end checked out.

 

I can't wait to compare the new configuration against my buddies 04 STI (stock besides Invidia exhaust). Secretly hoping the Spec.B will give the STI a run for its money... stealth mode FTW!

The Spec.B was finished yesterday.

 

Two things that stand out.. SPec.B had many exhaust valves that were completely fried. The Car's upper intake manifold gaskets were pretty tired too (probably leaking in cold weather I live way up in NH).

 

My thought is that the lean stock map + slight manifold leak = burnt valves over time.

 

Car is still only on the base map from the eTune (just turned logs in) but it really feels like the VF52 plus high flow down pipe and tune. Is how the car should have been sold? It really feels like the car was just kind of congested before the VF52,CNT DP and tune.

 

Dying to get a power map from Cyrotune and do some pulls and logging, hopefully on Monday. Definitely would recommend Cyrotune for open source e-tuning. They have a solid operation and are very informative.

I am going through pretty much the same thing right now, only slightly worse.

 

My 08 Spec.B has been flawless in terms of reliability up until this point. I have 160k miles on it, primarily highway and is completely stock. In fact, I just replaced my brakes for the first time at 155k. Yup..factory brakes for 155k miles.

 

Anyhow, I'll spare you the long bit about the diagnosis of the burnt valves as we already know that bit...CEL, low compression, same old story.

 

So the dealership gave me a best case quote of $3900 for a tear down, send the heads to a machine shop to get cleaned up and to replace damaged valves, buckets, etc.

 

When the machine shop got my heads they found cracks... (see attached jpgs)

Initially, the dealership told me that the cracks were around the spark plug ports and that they have seen them before and were not a replacement situation, but that mine were bad enough to need replacing...seeing the cracks in person, they were not by the spark plug holes. At least my focus went strait to the cracks near the valves. I need to look around the spark plug holes again. Aditionally, one of my valves supposedly had a chunk missing that was almost 2/5ths of the face of the valve.

 

So I had to purchase new head$ and bucket$, valves, etc. adding $1600

 

I asked how this happens and they said that the only explanation they have for this is running bad gas that isn't 91 or better octane. I said that is impossible for my car unless gas stations are lying as I have never put anything but 91 or better(when available) in my car. In fact I used to seek out the BPs with 92 octane until the price difference between the 91 and 92 became to high to justify. If I ever traveled and found 93, I'd damn near do a happy dance... so running less than 91 is just a crazy thought for me.

 

I called SoA to place a complaint about the cracks around the spark plug holes( as the dealership told me) before the new heads were ordered and I was able to actually see the cracks myself. I said that it must have been a casting issue because nothing could cause cracks around the spark plug ports beyond a defect. Right or wrong, that was my statement. They said they would call the dealership and then call me back. I called over a week ago, they called the dealer mid week last week, and I have yet to hear back from SoA myself. The service manager told me that he did mention to them the valve issue and discussed how it is a known issue. I am still waiting to hear anything back from SoA about any of it.

 

As I was looking at the heart of my car splayed out across the garage of the dealership, we discussed parts that may or may not be a good idea to replace for longevity/pm. We looked at my clutch and they said that I could use it without a problem as it only had been worn down to half of it's life and the flywheel looked good as well. He said I could order a clutch online and probably save some money instead of buying it strait from them, and also wouldn't mind if I did that with other parts as well. Knowing that a clutch replacement isn't cheap on labor, I decided I should take advantage and drop a new one in. I ordered the Exedy OEM replacement clutch kit(FJK1002) from Amazon for ~$300. It wasn't until it was delivered that I saw some people pointing to how the Spec.B clutch might be smaller than the STI clutch. However, this doesn't appear to be the case for the OEM replacement clutches from Exedy. Oh wait...while I was just grabbing the part numbers, I noticed that the clutch size difference is between the 06 Spec.B and STIs...the 07 and 08 Spec.Bs have the same diameter(240mm) as the STIs.

I was told that our flywheels are too thin to resurface as they are already lightened. The service manager thought mine looked good and could be reused, but the tech said to never reuse the flywheel with a new clutch.

 

So here is my current breakout:

 

Stock Shortblock is good, no scoring, leaking, etc...

New Heads with new valves, buckets, springs but Stock Cams

New Exedy OEM Clutch

New Flywheel OEM

Stock VF46 Turbo, has a little shaft play(tech says replace if can, SM says it should be fine)

 

 

Which leads me to seeking your advice/opinions on...

 

I am planning on moving to Berlin and am mixed on whether I should really take my Spec.B with me. It is a bit big with a less than stellar turning radius for living in that city, but would be awesome fun on the Autobahn. Gas is also way more expensive there...

 

If I laugh in the face of economical transportation in the EU and take my baby over there...I don't want it to blow up from trying to extract too much power or a failing turbo. However, having a bit more power would also be desirable(who would say no to that, right?).

 

Unlike SpecBot, I have my stock injectors. I've been digging and think they are around 565cc, but haven't found anything definitive on that.

 

I just picked up a Tactrix cable because I wanted to check my IDCs via logging. I guess reading about failing injectors scared me enough, but the dealership said they think they are fine. I'm not sure they really looked at them though.

 

Should I go ahead and replace the turbo, would you stick with the vf46 or go with the vf52?

 

Am I safe with stock injectors with a vf52?

 

I'd probably do the bulletproof TMIC mod if I went with the vf52...

 

I will also need the emissions to pass TUV inspection in Germany, so I am not sure if a high-flow catted downpipe will clear.

 

Clearly a tune would be involved.

 

Whatcha think?