08 SpecB top end rebuild analysis

[Xplosivo1]

Replace the turbo, your using a ticking time bomb. Either a BNR 16G or a VF52, they both use stock fueling and will give you more power.

[s_nold]

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.

 

On my subsequent visits to the dealer, I was told(and they did mention this as a potential cause from the beginning) that Subaru claims damage of this sort is caused by gas that is less than 91 octane. I was told this by both the service manager and the tech. I kinda took offense to that being the cause as I know what I put in the car. I have NEVER used anything less than 91 octane.. at least knowingly. In fact, I used to go out of my way to find the few gas stations that had 92(BP) until the price difference and hassle became prohibitive. That was a couple years back though.

 

So you might be wandering, what about the casting job that I complained was bad. Apparently something was miss-stated or mis-understood. Probably mis-understood on my part, as this "understanding" occurred over a quick phone call with the service manager.

 

How much sub 91 octane do you think it would take to kick off the events that then cause burnt valves and such?