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[Z06] C6Z started making some weird noises, video inside
C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
My oil pressure at operating temp and idle is 40-50 psi
I took apart one of the comp cams trunnions last night, not very pleased to see this much wear after only about 2500-3000 miles. it was worn enough that I could catch my fingernail on it. What's the chance that I've got others that are worn worse, could definitely explain the metal flakes in my filter. Sorry for the out of focus picture
Mine looked pretty much exactly like that and I had about the same mileage as you. I put the Straub kit in as well. I don't think that's going to fix your noise unless you find something other than worn trunnions in your valvetrain.
Mine looked pretty much exactly like that and I had about the same mileage as you. I put the Straub kit in as well. I don't think that's going to fix your noise unless you find something other than worn trunnions in your valvetrain.
I'm hoping for his sake the replacement will fix it. He's only torn one down so far. May be one that is really bad. Especially with all that metal in the filter.
I'm hoping for his sake the replacement will fix it. He's only torn one down so far. May be one that is really bad. Especially with all that metal in the filter.
I agree, The one that i tore down does not have enough wear to cause my noise, so unless I find one that is trashed I don't think that is my main issue. but it's a relatively cheap and easy thing to try before committing to pulling off heads and going deep
However, at least this issue is caught now instead of becoming another MAJOR issue down the road.
I definitely can't be 100% certain that this is the source of the noise I was hearing in my original video, but i was going through the underside of my car trying to rule out any vibrations from my recent exhaust upgrade as the source of the sound. Check out the video below as I bump the exhaust near the passenger side cat...
*Video edit - Removed video, I had a loose cat but it wasn't the source of the noise that matters.*
Fortunately for you I have the cat section I need to sell. I'm going catless. PM me if you want it. Maybe 7k miles at most on it. Never seen rain. ARH 3" Xpipe.
Fortunately for you I have the cat section I need to sell. I'm going catless. PM me if you want it. Maybe 7k miles at most on it. Never seen rain. ARH 3" Xpipe.
Thanks Omega, but I'll be pursuing the warranty route first, these are only a couple months old with 1000 miles on them. We will see what ARH has to say about it first.
How difficult is it to check/replace them? I think I have Comp and now I'm concerned. Lol. But I don't do the labor so curious on how many hours it would take to open her up.
I gutted the cats, put the new trunnion kit in and the noise is still there. I've checked clearance on exhaust and I even did a short run without belts to rule out any pulleys. Noise is still there. I think this basically leaves me with engine internals??? maybe a wrist pin on its way out or something. I've sent an oil sample off for analysis to see if maybe that can tell me if I've got a lot of wear going on.
I gutted the cats, put the new trunnion kit in and the noise is still there. I've checked clearance on exhaust and I even did a short run without belts to rule out any pulleys. Noise is still there. I think this basically leaves me with engine internals??? maybe a wrist pin on its way out or something. I've sent an oil sample off for analysis to see if maybe that can tell me if I've got a lot of wear going on.
A sad way to be parking her for winter
hard to tell in a video but It sounds rod bearing/piston wrist pin to me.
Lifters possibly? You could use a stethoscope to isolate the area??
At that point the heads have to come off anyway. Regardless it will be getting new lifters with the rebuild. I didn't have a collapsed lifter when I did the Straub trunnions.
At least I haven't had a catastrophic failure, as long as the crank and cam aren't damaged it shouldn't cost me outrageous amounts of money to do bearings, rods (maybe) and pistons.
My oil sample analysis came back today. I compared this with the universal averages for LS7's that can be seen on blackstone reports. Take a look at my Titanium levels. universal averages for these are 0-1 ppm over a typical oil interval period. I'm at 9 ppm over only 1500 kms...
Everything else looks to be more or less normal, the iron might be a little high for the interval period. I just had my valve guides re worked last year so I don't think it's the intake valves. That would leave me with Rods, which could definitely explain the noise.
I should also note that this oil sample was taken cold after the car sat for two weeks. I know for a completely proper sample you are supposed to get the oil up to temp and then sample mid stream during the drop so that particles and contaminants are suspended in the oil. I didn't want to run the old oil with the new rocker trunnions so I didn't fire it up before dropping the oil.
So there's a chance there may have been even higher titanium levels but over the two week period the heavier elements dropped out of suspension in the oil.
I read an LS7 blackstone report that had the guys Ti level at 5ppm and they said that worried them. Mine is almost double that and on a very short interval.
Seems I'm just a victim of bad luck... I pulled the motor and took it apart this week. Looks like cylinder #6 wrist pin was the source of this noise. Looks like my Z is getting a forged bottom end!
Seems I'm just a victim of bad luck... I pulled the motor and took it apart this week. Looks like cylinder #6 wrist pin was the source of this noise. Looks like my Z is getting a forged bottom end!
Did you find the source of the Ti? Take a close look at the sides of the connecting rods big end.
09-29-2016, 10:59 PM
