magnusonsubie

Couple spots today. DGM 08 GT on highway 101 southbound south of pacifica and a silver GT wagon with tint and debadged hatch in pacifica. Stopped to get gas at shell. I was in a yellow Mercedes 240D Edit: Also spotted a couple of Canadians cruising down highway 101 getting some fruit from a roadside stand. Great to meet you Scooby Fan and Scooby Two

With the release of the Grimmspeed intake today and the TMIC last January I have decided to start parts whoring for a decent upgrade hopefully next September. Want to get a JMP VF52, 850CC injectors, probably AVO turbo inlet and then some other engine dress up parts and install all of them when I get back to school next fall. Was thinking about getting a JDM spec B facelift front end and doing that swap but I'm really liking how much more angry and aggressive the USDM front end is in comparison to the JDM front ends.

shoulda come to subiefest too

A couple of my favorites from going out and shooting a bit Saturday night. Still learning how to use a camera as opposed to just turning a wrench.

I've got both my front and rear at home. I couldn't find the thread but I remember someone did it awhile ago somewhat seriously.

Talking with my instructor he suggested doing brinell and Rockwell hardness tests on different sections of the pistons to see if there's a difference between where the ringland failed and the opposite side. And if there is enough material present we will machine it down and try to do a Charpy break test on it.

If you're willing to ship them to me or at least the new OE one would be awesome. I talked to my professor about it yesterday and even he is interested to see what we find.

No it is not. It is the discontinued MachV wing. I got lucky and knew of one locally and when it came up for sale I jumped on it.

Lol I was thinking that it might be smaller then the rotors and I knew it was smaller then the calipers needed

15's won't clear lgt rotors as far as I know. But yes that is a good way to save weight

Naylors wagon and Madi by Gunnar Magnuson, on Flickr

or when its something heavy enough you can just use the scale on its own. Thats how I measured shipping my old suspension when I sold it.

Sometimes I do and that isn't far from my campus so I wouldn't have a problem swinging over on a weekend or something.

So for those of you that bought multiple sets if you want to donate a set to science I can give us all piece of mind as to their strength by cutting it up and running some different tests on them. Didn't think about it till after I ordered my pair last night

lol I'm in college right now and everytime I come home my parents look at my wagon and go "Oh thats new". Be realistic though. Set a goal of what you want out of your car and how much you're willing to spend. I have kinda just been winging it with my wagon which I've owned since Feb 2014 now and I'm $17,000 into it including the $10k price with 51k miles. I saw you had posted in the AVO 2.5i turbo thread as well and personally I wouldn't attempt to do that with your car. I would just do appearance and suspension for now. Theres a reason there isn't a huge market for engine mods for the 2.5i engine since there is a turbo engine in the same car available.

Original Post Alright guys I have a huge favor to ask. If anyone who has had their ringlands fail and have gotten a new shortblock or still has their original pistons sitting around I am taking a properties of materials lab class right now and at the end of the semester I get to choose my own project to test the properties and strengths of a material. If I could get all the pistons from the same shortblock labeled from the cylinders they came out of I might be able to break them and see if there is an inconsistency across pistons in our engines or if the pistons are just a weak material in general. Let me know if you'd be willing to help me out with this. I will gladly pay the shipping cost for the pistons to get to me but I can't really afford more then that. What was found from the tests done Abstract Comparing the hardness of the crown across all four pistons to observe any differences between the hardness top and bottom and where the piston four had ringland failure. Also observing the grain structures in polished samples underneath a microscope the engineer is able to see how different samples have dislocations and failed points in the cast aluminum piston. By performing these tests the engineer is able to come up with theories about why the piston had ringland failure. Introduction From 2005-2009 Subaru produced the Legacy GT and Outback XT vehicles in the United States equipped with the EJ255 turbocharged engine. Now that some of these vehicles are 10 years old and reaching higher mileage there are more and more instances appearing of ringland failure specifically on piston four. Many people have speculated that these failures occur due to the design of the engine as cylinder 4 is the rear drivers side which has the longest exhaust runner before the turbo. Another theory that people have come up with and tuners have somewhat proved is true as far as watching air fuel ratios when the turbo is spooling up creating boost. The pistons observed were out of a 2008 Outback that was on the stock tune for roughly 95000 miles, had an ECU (Engine Control Unit) update to what is known as stage one for 15000 miles and then the next 10000 miles consisted with an upgrade to a high flow catalytic converter and another ECU update to what is known as stage two. These ECU updates are purely a means to keep the car running correctly with proper fuel and air delivery. At roughly 120000 miles on the car the pistons tested came from was when the ringland failure occured. Procedure In this lab the independent variable was the cylinders which the piston came from. For the hardness test all four pistons were tested on the piston crown on the top and bottom of the piston with respect to how it is oriented in the engine. For the microscopy the sample from pistons were from piston three and piston four to be able to compare the failed section to a non failed section on a different piston. The dependent variable in this lab was the crystal structure of each metal sample observed under the microscope during the microscopy section. For the hardness testing section the dependent variable was the hardness of the different location tested. The controlled variables in this test were the same tools were used to prepare all samples observed. Also using the same microscope on the same zoom setting. For the hardness test the 1/16" diameter ball indenter and the Rockwell B scale was used to measure the hardness.  Results Figure 1 below shows the pattern for hardness testing the pistons. The results from the hardness test follow Figure 1 in Table 1. Test location Piston 1 Piston 2 Piston 3 Piston 4 1 54.2 55.9 54.9 44.3 2 51.2 54.7 55.4 54.1 Table 1: Hardness of Pistons. (This is just a circle showing where the hardness tests were completed, Test 1 was the top of the crown on the top skirt side, 2 was the top of the crown on the bottom skirt) Figure 1 Figure 2 below shows the original known ringland failure area. Figure 3 following shows the section of ringland that came apart upon creating the microscopy samples. Original Failure 2 Figure 2: Original Failure Piston #4 Failed section 1 Figure 3: More failure after cutting Figures 4-7 show the red dye test conducted to check for any cracks in the piston cross-section we cut away on piston three and four. Decking #3 Figure 4: Preparing piston 3 for the red dye test Decking #4.2 Figure 5: Preparing piston 4 for the red dye test Red Dye Test #3 Figure 6: Red dye test on piston 3 showing no cracks Red Dye Test #4.6 Figure 7: Crack in Ringland on Piston 4 Crack in #4.11 Figure 8: Piston four ringland failure crack Piston #3.6 Figure 9: Piston 3 microscopy Piston #4 Cross-Section Microscopy Figure 10: Piston 4 Microscopy Cross-section Discussion of Results Hardness tests were performed on the top, location one, and on the bottom, location two, as seen in figure 1, of the piston crowns. The original ringland failure occurred on the top side of piston four in the area visible in figure two and more failure was found and is shown in figure three. Rockwell B scale was used for the hardness tests on all four pistons to have the most accurate data. Each piston had multiple hardness test conducted in the same region that were 2.5 times the size of the penetrator away from the edge of the specimen and three times the size of the penetrator away from any 2 other penetrations. The Rockwell hardness numbers that were collected on pistons one, two, and three were from locations one and two and were all comparable to one another, the hardness numbers can be seen in Table 1: Hardness of Pistons. The hardness test numbers for piston four had a dramatic difference between the three other pistons and itself. The hardness test on piston four in location one had a similar value to the other location one tests on the three other pistons, but location two hardness number had a difference of 10.7 hardness compared to the average of the other three pistons. This difference in hardness number supplied the information that the hypereutectic cast aluminum piston from cylinder four, in test location one was relatively softer compared to the other pistons. This difference in material hardness is one possible conclusion as to why the piston’s ringland failed. The cause for this change in material hardness could be due to uneven burn across the crown of the piston, injector location, or excessively hot burn due to the factory tune lean condition when the fueling system changes over from closed loop to open loop that is pressured by the EPA emissions regulations. Conclusions cannot be drawn from this test though due to the possibility that the hardness of the piston four crown could have changed post-failure rather than pre-failure. A red dye test was completed on piston three and four while cutting pieces of the piston for the microscopy sample. It was found that there was a small fracture in piston four located in the ringland, this can be viewed in figure 7. The fracture was below the original ringland failure and appears to be a large fracture that would have most likely failed as well if the piston was continued to be used. One can see the cross section of piston four and the large failure in the ringland in figure 7 as compared to what a complete and functional ringland looks like in figure 6. In figure 6, piston three can be viewed which has no apparent cracks or fractures. For the next metallurgy experiment we conducted, we used cross-sectional areas from the ringlands from piston three and four to make microscopy samples from. After the samples were constructed they were only sanded and not polished. This was still more than enough preparation for analysis. The hypereutectic aluminum has silicon that is used to decrease the amount of contraction and expansion during cold starts of the engine. Piston three microscopy sample shows the silicon material that is present in the metal, which is the black area shown in the aluminum. This distribution can be seen in figure 9. Also the grain structure of figure 9 shows dislocations and grain boundaries that are non-uniform, giving the piston a greater hardness. The microscopy sample for piston four seen in figure 8 shows a extremely different grain structure and silicon content. The grain boundaries are more uniformed and straight compared to piston three, which leads to the conclusion that the material in piston four was annealed in some matter during its using. The annealing process is most likely the cause for the grain structure properties that would cause the metal to have a lower hardness number which can be confirmed with the results from the hardness testing that was conducted on the material. Figure 9 also shows a lack of silicon due to the lack of and poor distribution of black regions in the microscopy sample that represent the silicon. The lack of silicon in the piston four material would cause for the metal to expand and contract more so than an area that has silicon. In figure 8, a crack is shown with material on both sides of the crack. The crack was located between the bottom ringland and the piston skirt and can be seen in figure 10. On the left side of the figure there is a medium amount of silicon as compared to figure 9, but there is still so amount of dark spots on that side of the sample. On the right side of the ringland crack, there is almost no silicon present, and the small amount that is present is extremely light in color. This difference in silicon content in these different areas of the material could have led to the reason why the material cracked, due to different coefficients of contracting and expanding. The reason why the two different areas would have such a different amount of silicon content could again be due to an uneven burn across the crown of the piston, injector location, or excessively hot burn due to the factory tune running dangerously lean when switching from closed loop to open loop fueling parameters that is pressured by the EPA emissions regulations. This correlation would lead to annealing, and dispersion of silicon throughout the metal causing the hypereutectic material strengthening mechanism to be less effective. Conclusions After testing, it was concluded that the most likely source of ringland failures in the EJ255 engine can be traced to the hypereutectic cast aluminum piston composition and the close proximity of the ring package to the crown of the piston. Comparison of the collected data to a brand new factory piston would allow clearer conclusions about the microscopy data to be made and would be an excellent way to further this research. Solutions to this problem are available and commonly consist of rebuilding the engine with redesigned, aftermarket, forged pistons. The simple truth of these failures is that emissions regulations have pushed automotive engineers to work with ever narrower margins of error and this leads to these unforeseen problem areas in design. References "How to Avoid Blown Ringlands in Your Turbo Subaru." Viking Speed Shop. WordPress, 20 Aug. 2015. Web. 09 Dec. 2015. Tsuneishi, Scott. "The Truth Behind The Subaru EJ-Series Engines."SuperStreetOnline. N.p., 04 Feb. 2011. Web. 09 Dec. 2015. Special Thanks Thank you to OB2.5XT on the legacygt.com forum for generously donating his used pistons for this lab to be completed. Stan Hitchcock for helping with the machining and red dye testing of the pistons.

Ordered a set. If they don't look up to par on quality I'll take them into my properties of materials lab and cut them into little pieces and determine their strength.

Thanks guys! They are Rota Gravels

Photo dump coming tomorrow. They are going to be big too so try to use WiFi to view them if you are so inclined.

Saw a DGM 07 Spec B around 4 in the Marin headlands today. Appeared to have aftermarket exhaust. Freshly washed. Looked great!

My Yakima racks with a bike on top decrease my mpg by 5 gal when I drive between California and WA. When I've done the drive without a bike I've gotten 24-25 but with a bike its 18-19

^I like this guy. Hes smart. Almost too smart for our forum.

Got my bike out of the garage to take back to school with me tomorrow. Brakes are going to need a bleed before I go for a ride. Time to learn how to bleed avid brakes again such a fun experience.