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Rozsko

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  1. Thanks a lot guys! I am getting prepped for pulling the engine. I checked the bay the other day and while I could pull the covers for sure, it would be a pain in the back to do all checks. And I have ordered a few bits. Adjustable cam gears for the exhaust and LIC adjustable idlers for the intake. I just need to find the time to do it.
  2. Correct. This has only avcs on the intake. And you are absolutely right. Removing the valve cover and checking those clearances will be the next step. The only question is when, as I need to go back to Italy now, so in an other couple of weeks. Thanks a lot to both of you for following up on my problem so many times. I really appreciate all your insights and hints!
  3. Took a little while as I took samples with multiple options, but here you go. Everything except cyl#3 pressure is cranking. As you can see, you were absolutely right, the measurement I took yesterday was not correct. It is interesting that the hashes and those bumps present on yesterday intake capture is gone on today's zoom3 capture. Cyl#3 running compression is ~50psi, cranking compression is ~117psi. Back pressure on snap test is ~35psi I did not really have the time and peace yet to think over what I can see on this picture, but on the WOT intake capture there is a major difference between two and two cylinders.
  4. Well, I will repeat the test on cyl#3 then and see again. I am using a non-auto pico software, but I select the WPS in the probe setup, so that must not be a problem. LOL, that's exactly how it all started. I tried to scale the MAF sensor as I had an APS cold air intake that is bigger diameter then stock, but the AFR readings were jumping all over the place (+/- 1.5AFR). But I actually thought that is due to the misfire, as in that case only air is passing through the engine momentarily and that is obviously read by the wideband.
  5. Ok, so I got home and spend some time with the car. (I will leave the interesting part last ) here is the cranking waveform from the crankcase through the dip stick tube, synced to cyl#4: Not sure if you can see anything on this, but I cant. I know it is noisy, but all vacuum pulls are roughly the same shape and size. Cranking intake waveform, again synced to #4 cyl: not sure if got the piston char lined up right, but even if I did, I can't get my head around the information shown. And finally #3 cylinder pressure waveform. Surprisingly, the compression is not low, but high compared to the other 3 cylinders, and the bottom does not go into vacuum. cranking: Idle: Snap: I think the backpressure here quite high compared to the other three (~65psi vs ~25psi), not to mention the peak pressure which is ~450psi in #3 and ~250psi in the other three. Now, on the backpressure: No cat, straight through 3.5" exhaust (with silencer though, so the neighbors don't scream on me) #4 snap throttle: The reason why #4 for comparison is because it shares the uppipe tube with #3.
  6. it is not a known good waveform, but from the shop manual. So everything as far as engine assembly goes are brand new. Shortblock was ordered from IAG Performance, and since the block is converted to closed deck by them, I assume they skimmed it, but to be honest, I can't recall the specifics around that. Heads are also brand new. They are CNC ported Cosworth heads, so I don't think they were skimmed. Headgaskets are Cosworth 0.78mm.
  7. So as I look at these diagrams more and more, I just realized, that the advance/retard that we see on the pressure waveforms is about 5degree.I think earlier did mention that the LH and RH cams dont exactly line up. Guess what, the difference is about 5 degree. The LH cam signal is advanced compared to the RH and it seems both the intake and exhaust cams are advanced on cyl#2. So it is not cyl#1 that is late as the RH CAM signal perfectly lines up with the crank.
  8. No, these OE Subaru cams and are not adjustable. Exhaust is fixed, Intake is variable. I can, but what should be the ideal? I tried already with different settings like 100k, 200k, 500k, but did not really see any difference in the smoothness or detaildness of the curve. I am talking about the second TDC at 360 degree. if you see that ramp down from 0 psi to -10psi, that should be sort of straight or at least one smooth straightish (if that's a word ) curve. But if you look at it there is a little hump which I think is the IVO as if I measure the duration from that to the IVC event, it is roughly 226 degrees which is the total duration of the cam (although that is with the 1mm lift) as per the spec.
  9. Thanks a lot Steve for the taking the time to take a look at this and reply. Those are great suggestions and I will certainly do those when I get back home in 2 weeks. They are 120 and 137 psi. Yeah, me too. And that was always in the plan to do, but unfortunately I had only a few hours to play before I had to leave. Also the thing that I did not mention yet but makes me more and more curious to check the other two cylinders is that cyl#3 is the nosiest cylinder of all 4. One more question in my mind regarding the late intake cam on cyl#1 is that how can that be if the right cam perfectly lines up with the crank signal and TDC indicated by the pressure peak perfectly lines up with the 5th spike of the crank signal which is TDC. So if everything is in sync, then how can it be late? the vacuum is -3.2psi on cyl#1 and -2.8psi on cyl#2 Yes, I follow your line of thought, but I would have thought that the compression is lower becasue of the late intake (opening - I think the little bump in the descending pressure after TDC is the IVO?) closing as in this case there will be less air trapped in the cylinder to compress.
  10. Cyl#1 idle: Cyl#2 idle: So, the red and blue sections are mareked based on the Cosworth spec, measured at 1mm lift. Now to me it seems as if the exhaust would open roughly 9 degrees earlier then spec and the intake would close roughly 20 and 15 degrees earlier then spec. What I am not sure about if this could be due to the 1mm lift as obviously before the valves reach 1mm lift they already start flowing some volume as long as they leave their seat. Otherwise I can't see anything obvious on these charts. do you guys see anything suspicious?
  11. Cylinder#2 cranking compression: Cylinder#1 cranking comression: The standard spec in the shop manual is 142-171 psi and the minimal limit is 128psi, this tells me that there is certainly something wrong, especially considering that I have 8.5CR Mahle pistons instead of the OEM 8.2. Although I am not sure if this is casued by some cam timing issue. As you can see, there is not much happening at the bottom of the chart, and this on its own is very strange to me. Idle compression graphs to follow. oh and btw, the WPS signal is 100 times nicer then the cheap ebay sensor's. I think where the 8bit scope suffers to show all the details is at the low pressure range where over time there is little change.
  12. 100us=0.1ms But other then that I fully agree. I bought a cheap one from eBay to see how it is going and it proves to be wrong. Now my worry is the scope itself, as I did not go with the Pico autodiagnostic one, but the generic only which is 8bit vertical resolution. The only problem is that I won't have the wps before I need to leave home next Monday. So it will be an other few weeks until I can get to the car again.
  13. Little update, jut so that you have something to read. I contacted the USB Autoscope guys in Ukraine. The whole package is not too expensive (well, relative to the Pico stuff), but the only way they accept payment is through Western Union. Unfortunately they don't offer any buyer protection, like PayPal, so I was considering driving the car to Ukraine, as it is neighborhood country to Hungary. The headquarter is quite far, but they recommended some techs near the border who can do the diagnostic. This way I could avoid buying the kit and pay only for the diagnostic. So I was ready to roll, but then they figured out my car is far from stock and they backed out saying it would require a lot more time to diagnose as the standard process is for OE setups. Long story short, I ended up ordering a Pico WPS transducer, although pulling the engine and disassemble it would be cheaper, I just don't prefer that until I am really convinced it is necessary. Anyhow, I am not sure if the transducer will arrive next week, while I am home. If it will, then I will post up some more pics on the results, if not then couple of more weeks will need to pass, until I get my hands dirty again.
  14. Ha ha! I love tst seminars. I already have payed for couple of their premium videos. This one will be a nice addition to the list. Thanks
  15. I have an ignition lead going from the coil to the plug and have a Hantek capacitive clamp attached to it. Never thought to measure current on them, but I can try. I spend so much time on this yet, so a little more doesn't matter. I know. Unfortunately at the time the block was put together, I wasn't focusing on these things, as I have never thought it will go wrong. And because of that I did not record these numbers and was totally relying on the tech who put together the engine. Ok, so after the build, I had brand new DW850 incetors, and recently I changed to a set of ID1050X as they provide PnP calibration data for the Link ECUs. These are brand new too.
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