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Melting Wastegate Lines

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Old Feb 26, 2025 | 03:55 PM
  #21  
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Your commanded timing looks to match your table, so I don't see any ign retard or anything strange going on there. The table looks reasonable to me.

What immediately sticks out to me is I can't find your AFR (wbo2) reading. The AFR graph is just stuck at 10.4 for the whole log, showing a big discrepancy between target and actual AFR (known as AFR error) unless I'm missing something, this looks pretty concerning to me. Your AFR targets look reasonable but I see no wbo2 reading in your logs, so I have no idea what your actual AFR's are.

I could just be missing something silly though, curious what others think.

Old Feb 26, 2025 | 04:01 PM
  #22  
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Originally Posted by Fireindc
Your commanded timing looks to match your table, so I don't see any ign retard or anything strange going on there. The table looks reasonable to me.

What immediately sticks out to me is I can't find your AFR (wbo2) reading. The AFR graph is just stuck at 10.4 for the whole log, showing a big discrepancy between target and actual AFR (known as AFR error) unless I'm missing something, this looks pretty concerning to me. Your AFR targets look reasonable but I see no wbo2 reading in your logs, so I have no idea what your actual AFR's are.

I could just be missing something silly though, curious what others think.
Out of curiousity, what paratmers are you looking at to verify that. I have every single retard/advance option on the log viewer and I have a feeling I'm missing actual vs. commanded somewhere that should've made this way easier. As for AFR, I see that too and that is super weird. I use shadowdash display constantly so i know the wideband works. I've attached a slightly older log (no ignition changes) that I found on my laptop as a reference.
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File Type: mlg
2025-01-14_12.38.37.mlg (1.63 MB, 22 views)
Old Feb 26, 2025 | 04:18 PM
  #23  
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Originally Posted by tfbmiata
Out of curiousity, what paratmers are you looking at to verify that. I have every single retard/advance option on the log viewer and I have a feeling I'm missing actual vs. commanded somewhere that should've made this way easier. As for AFR, I see that too and that is super weird. I use shadowdash display constantly so i know the wideband works. I've attached a slightly older log (no ignition changes) that I found on my laptop as a reference.
The older log you just attached has AFR's as expected. I'm not sure why the latest log has that issue, though I don't see that EGO is pulling fuel at WOT. It's still at 100% EGO cor1 during the WOT boosted pulls which makes me think even despite the afr error it's not tuned to have much if any ego authority at WOT. I'd have to dig into your tune to confirm that though.

As for comparing the timing, I'm looking at the graph for your "SPK: Spark Table 1" to see what your table value is, and comparing that to "SPK: Spark Advance" which is the total advance your ECU is commanding. Basically if any corrections were happening you'd see a difference there, no need to look through every single different retard/advance setting - though I did that too for peace of mind and didn't see anything.
Old Feb 26, 2025 | 10:10 PM
  #24  
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The street won't see enough extended load to get IATs hot enough to retard in most cases.

I would search for that setting and ensure it's arranged properly.
Old Feb 27, 2025 | 10:56 AM
  #25  
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Originally Posted by sixshooter
The street won't see enough extended load to get IATs hot enough to retard in most cases.

I would search for that setting and ensure it's arranged properly.
I'll see what I cn find. For reference, on the day of my last track day, I had IATs in my ShadowDash and they never cleared 70F. It was a very cold day. I'm WFH today so i'm going to try to pull lthe logs from the track day and see if any of the logs show some type of session retarding.
Old Feb 27, 2025 | 03:36 PM
  #26  
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Attached is my log from the session where the silicone replacement line burst into flames. (....14.07) I had to zip it to be under the 20MB file size limit.

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Old Apr 17, 2025 | 11:22 PM
  #27  
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As an final update to this thread, my AN3 stainless line is working perfect so far. No melting and as far as I can tell the boost is held in check to wastegate pressure.
Old May 6, 2025 | 10:46 AM
  #28  
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Originally Posted by tfbmiata
As an final update to this thread, my AN3 stainless line is working perfect so far. No melting and as far as I can tell the boost is held in check to wastegate pressure.
Good to hear. Me personally, I'd add some extra heatshielding around the manifold portion and perhaps a heatshield on the chassis to protect the brake components. That stuff is getting crazy hot and just a good idea imo.
Old May 7, 2025 | 10:18 AM
  #29  
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Originally Posted by SlowTeg
Good to hear. Me personally, I'd add some extra heatshielding around the manifold portion and perhaps a heatshield on the chassis to protect the brake components. That stuff is getting crazy hot and just a good idea imo.
I have the exhaust manifold and now the dump tube covered in a fiberglass + corregated aluminum thing form DEI. I did not have the dump tube covered prior to my last track day. The last one I melted it on I didn't have any heat wrap. This last track day I did with the stainless steel line, I didn't have any issues with the wastegate line. I did end up blowing through the external wastegate's diaphragm and had to replace it.
Old May 7, 2025 | 11:39 AM
  #30  
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Originally Posted by tfbmiata
I have the exhaust manifold and now the dump tube covered in a fiberglass + corregated aluminum thing form DEI. I did not have the dump tube covered prior to my last track day. The last one I melted it on I didn't have any heat wrap. This last track day I did with the stainless steel line, I didn't have any issues with the wastegate line. I did end up blowing through the external wastegate's diaphragm and had to replace it.
That's good to hear nothing melted. Ya I think some heatshielding for the manifold and the surrounding components is critical on a track car, especially with the brake master cylinder not too far away. That external wastegate placement is going to make it tough to keep cool and not destroying the diaphragm. That's one thing I don't like about external wastegates, granted I've seen flappers fail on internal wastegates as well. I think someone else mentioned it above, but I believe there are water cooled wastegates to specifically fix this problem. You might have to look into it..
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