1985 Monte Carlo SS known as Barney

[SSLance]

So this is my normal screen layout



This is the scaling settings on the AFR in lower right.



And here is the video zoomed in showing the AFR going yellow at times.



It very well could have been going lean on the straights for some reason.

[SSLance]

This is a longer video that shows my whole 2nd session. First time at this track, first two sessions total washouts, with no instructor. Just me trying to find my way around and dodge P-cars...



Total blast...

[carbuff]

Lance,

I'm not sure about the system you are using, but the HP and Dominator systems are generally always logging when the vehicle is running. At least I have mine set up to do that, I think that was the default (been a long time since I had to make that choice).

Might be worth a look in the Holley program (you can use their tuning software and not just the handheld, correct?) to see if any logs are available.

Good luck!

[SSLance]

Originally Posted by carbuff

Lance,

I'm not sure about the system you are using, but the HP and Dominator systems are generally always logging when the vehicle is running. At least I have mine set up to do that, I think that was the default (been a long time since I had to make that choice).

Might be worth a look in the Holley program (you can use their tuning software and not just the handheld, correct?) to see if any logs are available.

Good luck!

Thanks. I have it set to only log when manually started and stopped.

I watched the other video in the wet again and the screen was easier to see then. It is probably spiking rich when it flashed yellow, not lean...that has kinda been its MO since we started tuning it.

We'll figure it out, fix it and move on. Part of the deal...

[SSLance]

More progress made today.

Figured out a way to pull the engine with car on the lift.



All kinds of room



Here is passenger side head. All looks good, just a bit more oil on #4 exhaust valve.



Tops of all of the pistons look normalish as do the cylinder walls.



This is #4, the one in question.



Popped #4 out and found this.







Multiple rings are broken in multiple spots and the top edge of the piston has started melting away. Hard to tell what happened first, oil ring could have failed, let oil in chamber which may have raised compression just enough to cause detonation raising temps above what piston could handle. One or multiple rings could have been just a bit tight, got a bit too hot and broke causing loss of compression. Or something with cooling system could have caused an air pocket, causing that cylinder to get just a bit hot and start the meltdown. It'll be interesting to see if any rings are broken in any other cylinders, haven't pulled any other pistons out yet.

Everything else looks excellent though. Bottom of pan was clean, cylinder walls are unscathed, head gasket looked good, basically you wouldn't know there was problem if not for that one piston. So glad I stopped when I did, that piston was one straight away from exploding.

Bearings look pretty good still.



I won't, but I literally could put a new piston with new rings on that rod and bolt it all back together again and I'm sure it would be fine.

More than likely unless it's stupid expensive it'll get new forged rods and pistons and a refresh on the bearings and rings and a good clean up. I may even consider a cam change to bring things more in line with the rest of the build. We'll see.

No hurry to put it back together though, it needs a new clutch disc and I may put a new accessory drive setup on the front as well as the engine refresh so this will be a bit of an extended project. Pretty dang happy I still have so many good parts left though, could have been much worse.

[WSSix]

Sorry to see this happen, Lance. LS swap time or sticking with the stroker?

[SSLance]

Why would I LS swap at this point?

That would just be silly...