[Z06] How Many Z06 Owners Are Running Solid Stainless Exhaust Valves?
10-03-2012, 02:16 AM
#101
Burning Brakes
I thought the exhaust valves in the LS3 were solid.
http://forums.corvetteforum.com/c6-c...s3-valves.html
http://www.katechengines.com/perform...gine-packages/
http://www.chevyhardcore.com/news/ne...ormance-parts/
http://forums.corvetteforum.com/c6-c...s3-valves.html
http://www.katechengines.com/perform...gine-packages/
http://www.chevyhardcore.com/news/ne...ormance-parts/
Last edited by Rock36; 10-03-2012 at 02:50 AM.
10-03-2012, 02:43 AM
#102
Racer
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My bad, guess I was mistaken after all!
But I'm pretty sure LS3 does not have titanium intake valves, only hollow stem stainless. Or am I mistaken on that as well?
I saw it on that TV show about the different generations of small blocks, where they had an original 350, and LS1 and LS3. They claimed the LS3 had sodium valves to aid heat transfer. I was surprised to be honest, turns out it's wrong after all.
But I'm pretty sure LS3 does not have titanium intake valves, only hollow stem stainless. Or am I mistaken on that as well?
I saw it on that TV show about the different generations of small blocks, where they had an original 350, and LS1 and LS3. They claimed the LS3 had sodium valves to aid heat transfer. I was surprised to be honest, turns out it's wrong after all.
10-03-2012, 08:12 AM
#105
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Well considering some cars has failed as early as 5000 miles that are completely stock and others at 20 to 30 k that are cammed and tuned is the problem that has left us all chasing our tails. How can it be a Guide Wear Issue at 5k on a bone stock car? I am starting to wonder if it is not an overev / missed gear problem. I have seen several yella terras broken on LS3's from this so on the LS7 it just goes to the next weakest point. Just a thought. Either way I bought a set of Brodix heads from Richard at WCCH just to be safe. Talking with him he seems 100% sure the valve / guide is the issue. He told me directly that they are simply too thin to take any kind of abuse.
10-03-2012, 08:46 AM
#106
Team Owner
Thread Starter
Well considering some cars has failed as early as 5000 miles that are completely stock and others at 20 to 30 k that are cammed and tuned is the problem that has left us all chasing our tails. How can it be a Guide Wear Issue at 5k on a bone stock car? I am starting to wonder if it is not an overev / missed gear problem. I have seen several yella terras broken on LS3's from this so on the LS7 it just goes to the next weakest point. Just a thought. Either way I bought a set of Brodix heads from Richard at WCCH just to be safe. Talking with him he seems 100% sure the valve / guide is the issue. He told me directly that they are simply too thin to take any kind of abuse.
10-03-2012, 08:51 AM
#107
Safety Car
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Information I've received says that a lot of guides/seats are delivered already out of spec or near out of spec from the Vendor in Canada that makes the heads.
Remember, to machine the valve seat requires utilizing the head's guides for the seat cutting tool. If the guide is already out of spec then the valve seat will be cut out of spec, losing concentricity with the valve. As the valve repeatedly impacts on a non-concentric cut seat with a loose guide it fatigues over a period of time as the valve hits the seat at odd angles. Then... Viola, the head snaps off.
Remember, to machine the valve seat requires utilizing the head's guides for the seat cutting tool. If the guide is already out of spec then the valve seat will be cut out of spec, losing concentricity with the valve. As the valve repeatedly impacts on a non-concentric cut seat with a loose guide it fatigues over a period of time as the valve hits the seat at odd angles. Then... Viola, the head snaps off.
10-03-2012, 09:18 AM
#108
Team Owner
Thread Starter
Information I've received says that a lot of guides/seats are delivered already out of spec or near out of spec from the Vendor in Canada that makes the heads.
Remember, to machine the valve seat requires utilizing the head's guides for the seat cutting tool. If the guide is already out of spec then the valve seat will be cut out of spec, losing concentricity with the valve. As the valve repeatedly impacts on a non-concentric cut seat with a loose guide it fatigues over a period of time as the valve hits the seat at odd angles. Then... Viola, the head snaps off.
Remember, to machine the valve seat requires utilizing the head's guides for the seat cutting tool. If the guide is already out of spec then the valve seat will be cut out of spec, losing concentricity with the valve. As the valve repeatedly impacts on a non-concentric cut seat with a loose guide it fatigues over a period of time as the valve hits the seat at odd angles. Then... Viola, the head snaps off.
The latest information that I got centers around the valves themselves and "differences" in them.
So it could be both the valves and the guides, or it could be the valves or the guides. That's why I got rid of both.
But your theory above on the mass produced stock heads, I have heard elsewhere as well. It seems tp make sense, and I feel a lot more comfortable after having the work done on my heads
I agree, that it's not just guide wear, or bettter put, not consistently guide wear that might be at the root of this matter. The potential for poorly crafted parts like the valves as well as the guides, exist.
The inconsistent wall thickness of the hollow stemmed valves is probably playing a role as well, as well as the consistency or lack thereof, of the weld.
That was described here:
http://forums.corvetteforum.com/c6-z...post1581414149
http://forums.corvetteforum.com/c6-z...post1581427075
http://forums.corvetteforum.com/c6-z...post1581422693
The valves when they fail, often times fail at or near the weld.
Look at the pictures of the failure in this last 2009. At this time, I am waiting to hear more information about these welds, and the part number change and how the two may be related.
But the point is, it's not just valve guide wear.
I'm beginning to wonder if there were not QC issues with some of the valves themselves, and not just the guides.
I certainly don't know the answer, in fact this whole matter leaves more questions than it does answers. But like any other concerned owner, and Z06 enthusiast, I would wonder about the two areas which are being heavily discussed. The guides, and the valves.
Last edited by '06 Quicksilver Z06; 10-03-2012 at 09:26 AM.
10-03-2012, 09:20 AM
#109
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Information I've received says that a lot of guides/seats are delivered already out of spec or near out of spec from the Vendor in Canada that makes the heads.
Remember, to machine the valve seat requires utilizing the head's guides for the seat cutting tool. If the guide is already out of spec then the valve seat will be cut out of spec, losing concentricity with the valve. As the valve repeatedly impacts on a non-concentric cut seat with a loose guide it fatigues over a period of time as the valve hits the seat at odd angles. Then... Viola, the head snaps off.
Remember, to machine the valve seat requires utilizing the head's guides for the seat cutting tool. If the guide is already out of spec then the valve seat will be cut out of spec, losing concentricity with the valve. As the valve repeatedly impacts on a non-concentric cut seat with a loose guide it fatigues over a period of time as the valve hits the seat at odd angles. Then... Viola, the head snaps off.
Last edited by torqjunkie; 10-03-2012 at 09:38 AM.
10-03-2012, 09:51 AM
#110
Melting Slicks
Interesting theory.
The latest information that I got centers around the valves themselves and "differences" in them.
So it could be both the valves and the guides, or it could be the valves or the guides. That's why I got rid of both.
But your theory above on the mass produced stock heads, I have heard elsewhere as well. It seems tp make sense, and I feel a lot more comfortable after having the work done on my heads
I agree, that it's not just guide wear, or bettter put, not consistently guide wear that might be at the root of this matter. The potential for poorly crafted parts like the valves as well as the guides, exist.
The inconsistent wall thickness of the hollow stemmed valves is probably playing a role as well, as well as the consistency or lack thereof, of the weld.
That was described here:
http://forums.corvetteforum.com/c6-z...post1581414149
http://forums.corvetteforum.com/c6-z...post1581427075
http://forums.corvetteforum.com/c6-z...post1581422693
The valves when they fail, often times fail at or near the weld.
Look at the pictures of the failure in this last 2009. At this time, I am waiting to hear more information about these welds, and the part number change and how the two may be related.
But the point is, it's not just valve guide wear.
I'm beginning to wonder if there were not QC issues with some of the valves themselves, and not just the guides.
I certainly don't know the answer, in fact this whole matter leaves more questions than it does answers. But like any other concerned owner, and Z06 enthusiast, I would wonder about the two areas which are being heavily discussed. The guides, and the valves.
The latest information that I got centers around the valves themselves and "differences" in them.
So it could be both the valves and the guides, or it could be the valves or the guides. That's why I got rid of both.
But your theory above on the mass produced stock heads, I have heard elsewhere as well. It seems tp make sense, and I feel a lot more comfortable after having the work done on my heads
I agree, that it's not just guide wear, or bettter put, not consistently guide wear that might be at the root of this matter. The potential for poorly crafted parts like the valves as well as the guides, exist.
The inconsistent wall thickness of the hollow stemmed valves is probably playing a role as well, as well as the consistency or lack thereof, of the weld.
That was described here:
http://forums.corvetteforum.com/c6-z...post1581414149
http://forums.corvetteforum.com/c6-z...post1581427075
http://forums.corvetteforum.com/c6-z...post1581422693
The valves when they fail, often times fail at or near the weld.
Look at the pictures of the failure in this last 2009. At this time, I am waiting to hear more information about these welds, and the part number change and how the two may be related.
But the point is, it's not just valve guide wear.
I'm beginning to wonder if there were not QC issues with some of the valves themselves, and not just the guides.
I certainly don't know the answer, in fact this whole matter leaves more questions than it does answers. But like any other concerned owner, and Z06 enthusiast, I would wonder about the two areas which are being heavily discussed. The guides, and the valves.
Just because they fail at or near the weld doesn't mean its the valve problem. Sure its the weak point on the valve but thats like saying if you get punched in the face and your nose shatters causing you to lose the fight its a nose problem. No, I think it was the punch to the face. If you blocked that punch your nose wouldn't be broken.
The guides are the problem. I think you could safely run the sodium filled no problem as long as the guides are in spec. The effect on the exhaust valve is from the guides being out of spec causing heat problems and or vibration and chatter. If the guides were in spec the issue would be negated and the sodium filled valve wouldn't have any problems and be operating outside of its spec. Its used in many other applications without issue.
I would personally rather stick to what the engine was designed to run. Taking an extra step is more like an insurance policy. To each their own though. If it makes you sleep better than it was worth it.
10-03-2012, 11:36 AM
#111
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Check out the 2:30 mark in the vid. Yes it is relative to the thread.
http://www.youtube.com/watch?v=s9JOg...feature=colike
http://www.youtube.com/watch?v=s9JOg...feature=colike
10-03-2012, 12:21 PM
#112
Melting Slicks
Check out the 2:30 mark in the vid. Yes it is relative to the thread.
http://www.youtube.com/watch?v=s9JOg...feature=colike
http://www.youtube.com/watch?v=s9JOg...feature=colike
Check the sticky above. I posted the same link yesterday and the time! Great minds think alike.
10-03-2012, 12:36 PM
#113
Interesting theory.
The latest information that I got centers around the valves themselves and "differences" in them.
So it could be both the valves and the guides, or it could be the valves or the guides. That's why I got rid of both.
But your theory above on the mass produced stock heads, I have heard elsewhere as well. It seems tp make sense, and I feel a lot more comfortable after having the work done on my heads
I agree, that it's not just guide wear, or bettter put, not consistently guide wear that might be at the root of this matter. The potential for poorly crafted parts like the valves as well as the guides, exist.
The inconsistent wall thickness of the hollow stemmed valves is probably playing a role as well, as well as the consistency or lack thereof, of the weld.
That was described here:
http://forums.corvetteforum.com/c6-z...post1581414149
http://forums.corvetteforum.com/c6-z...post1581427075
http://forums.corvetteforum.com/c6-z...post1581422693
The valves when they fail, often times fail at or near the weld.
Look at the pictures of the failure in this last 2009. At this time, I am waiting to hear more information about these welds, and the part number change and how the two may be related.
But the point is, it's not just valve guide wear.
I'm beginning to wonder if there were not QC issues with some of the valves themselves, and not just the guides.
I certainly don't know the answer, in fact this whole matter leaves more questions than it does answers. But like any other concerned owner, and Z06 enthusiast, I would wonder about the two areas which are being heavily discussed. The guides, and the valves.
The latest information that I got centers around the valves themselves and "differences" in them.
So it could be both the valves and the guides, or it could be the valves or the guides. That's why I got rid of both.
But your theory above on the mass produced stock heads, I have heard elsewhere as well. It seems tp make sense, and I feel a lot more comfortable after having the work done on my heads
I agree, that it's not just guide wear, or bettter put, not consistently guide wear that might be at the root of this matter. The potential for poorly crafted parts like the valves as well as the guides, exist.
The inconsistent wall thickness of the hollow stemmed valves is probably playing a role as well, as well as the consistency or lack thereof, of the weld.
That was described here:
http://forums.corvetteforum.com/c6-z...post1581414149
http://forums.corvetteforum.com/c6-z...post1581427075
http://forums.corvetteforum.com/c6-z...post1581422693
The valves when they fail, often times fail at or near the weld.
Look at the pictures of the failure in this last 2009. At this time, I am waiting to hear more information about these welds, and the part number change and how the two may be related.
But the point is, it's not just valve guide wear.
I'm beginning to wonder if there were not QC issues with some of the valves themselves, and not just the guides.
I certainly don't know the answer, in fact this whole matter leaves more questions than it does answers. But like any other concerned owner, and Z06 enthusiast, I would wonder about the two areas which are being heavily discussed. The guides, and the valves.
I could be added to this list or will be in the next 2-3 weeks. I decided to go with Jeremy Formoto at Fasterproms because of his reputation as a tuner and the fact that he lives 11 miles from me. He is going to do a fully ported head job, stainless valves, new stock valve guides, cam, headers w/hi flow cats, comp dual springs, titanium retainers, etc..
One of the parts I asked him about was the bronze valve guides. While he said he could install them, he recommended just using new OEM guides as he does in his builds.
10-03-2012, 12:49 PM
#114
Safety Car
11-15-2012, 08:32 AM
#115
Advanced
from my experience with my 07 zo6 purchased new,DONT DRIVE after camkit install with those hollow exhaust valves in heads,,,my ls7 lasted under 2 months and 400 miles after cam install and a few track runs before valve dropped and piston-cylinder came apart... so beware!
11-15-2012, 10:18 AM
#116
Team Owner
from my experience with my 07 zo6 purchased new,DONT DRIVE after camkit install with those hollow exhaust valves in heads,,,my ls7 lasted under 2 months and 400 miles after cam install and a few track runs before valve dropped and piston-cylinder came apart... so beware!
11-15-2012, 10:44 AM
#117
Le Mans Master
A little late to respond.
I had lots of blue smoke when my engine would come down from high revs after about 22 track days. Sent the car to ECS and found both heads were shot except for the Ti valves.
-Replace 16x valve guides with bronze guides, valve job
-New vavlespring set
-APR head studs
-Mill and bead blast
-New plugs
-Stainless Steel valves
-New Valve seats
-New 02 sensors
Approx $2500 for repair, car had 16k miles went it, and now has about 19k. So far so good.
I had lots of blue smoke when my engine would come down from high revs after about 22 track days. Sent the car to ECS and found both heads were shot except for the Ti valves.
-Replace 16x valve guides with bronze guides, valve job
-New vavlespring set
-APR head studs
-Mill and bead blast
-New plugs
-Stainless Steel valves
-New Valve seats
-New 02 sensors
Approx $2500 for repair, car had 16k miles went it, and now has about 19k. So far so good.
11-15-2012, 04:00 PM
#118
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I have just received my new brodix heads from WCCH. They have solid stainless valves in them. I did this for peace of mind on my 07 Z06. I will install them in the spring when I get the car out of storage. I am still trying to figure out which cam to use.
11-15-2012, 04:23 PM
#119
Racer
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11-15-2012, 04:51 PM
#120
I am looking into upgrading the stock valves and guides but the builder I want to use says that solid valves aren't ideal for a high reving engine like the ls7. He recommends sodium filled valves because they are a little lighter. Anyone running sodium filled valves other than the OEM? opinions?
Last edited by logan1080; 11-15-2012 at 04:55 PM.