[Z06] Talked to Rich at WCCH today...
08-29-2012, 09:50 PM
#1
Safety Car
Thread Starter
Talked to Rich at WCCH today...
Thought Id share a quick conversation I had with Rich today from WCCH. I was looking at purchasing a set of used LS7 heads that would need some machine work. Didn't get them, they were sold to someone else, but this morning I decided to get a quote on what cost would be to make these like new again. As we were talking, mind you, I'm in FL and called at 9am. That's 6am in Cali. Answered on second ring. 
Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad. He said that when they started getting in so many worn LS7 heads, they had to reinvest in all new equipment to meet the demand and needs. He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves.
Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set
But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.
Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad. He said that when they started getting in so many worn LS7 heads, they had to reinvest in all new equipment to meet the demand and needs. He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves. Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set
But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
Last edited by forg0tmypen; 08-29-2012 at 09:53 PM.
08-29-2012, 10:07 PM
#2
Burning Brakes
Thought Id share a quick conversation I had with Rich today from WCCH. I was looking at purchasing a set of used LS7 heads that would need some machine work. Didn't get them, they were sold to someone else, but this morning I decided to get a quote on what cost would be to make these like new again. As we were talking, mind you, I'm in FL and called at 9am. That's 6am in Cali. Answered on second ring. Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad. He said that when they started getting in so many worn LS7 heads, they had to reinvest in all new equipment to meet the demand and needs. He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves.
Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.
Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad. He said that when they started getting in so many worn LS7 heads, they had to reinvest in all new equipment to meet the demand and needs. He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves. Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set
But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
08-29-2012, 10:34 PM
#4
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08-29-2012, 10:35 PM
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How come we dont see all of these issues with LS6 engines? They featured hollow stemed, sodium filled exhaust valves. I not sure but I think it could be the whole combination of big cylinder, big intake valve, small exhaust valve. Maybe there just isnt enough flow through the exhaust causing the valve to take on alot of heat. Or maybe the added compression transfers too much heat up the stem to the guide. Maybe tuners and GM are running them leaner for more power or cleaner burn. Has there been any E85 users have failures? I havent noticed any so I'm wondering if its linked to EGTs.
08-29-2012, 10:40 PM
#6
Maybe things have changed since then.
08-29-2012, 10:50 PM
#7
.. but this morning I decided to get a quote on what cost would be to make these like new again. As we were talking, mind you, I'm in FL and called at 9am. That's 6am in Cali. Answered on second ring. Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad.
Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad.Hopefully not, because that motor is a lot more expensive to replace even than an LS7.
He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves.
Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.
Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves. Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set
But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
OEM guides are steel aren't they? They know the specifics but there is no "excessive play" of my valves because the guides are not worn down as so many people have been posting. The only thing I know I do different than most is drive the **** out of my car every second I'm in it, and maybe that's why she's been so good to me.
So there you have it. By my account, the OEM valves and guides in LS7 heads are perfectly fine, even when used on a mild-aggressive h/c/i setup.
So there you have it. By my account, the OEM valves and guides in LS7 heads are perfectly fine, even when used on a mild-aggressive h/c/i setup.
http://forums.corvetteforum.com/c6-z...n-an-09-a.html
I recall the post by hoefi listing .0037 as the service limit. but if it's .0025", as the poster in the above thread says that Katech told him, then I doubt that pure tactile sensation would allow most human beings to distinguish from .0025 to .0037 inches.
I don't know about you but I don't believe that I can "feel" the difference in terms of "excessive play" between say, .0037 inches and .0041 inches.
Last edited by '06 Quicksilver Z06; 08-29-2012 at 11:11 PM.
08-29-2012, 11:04 PM
#8
Burning Brakes
Thought Id share a quick conversation I had with Rich today from WCCH. I was looking at purchasing a set of used LS7 heads that would need some machine work. Didn't get them, they were sold to someone else, but this morning I decided to get a quote on what cost would be to make these like new again. As we were talking, mind you, I'm in FL and called at 9am. That's 6am in Cali. Answered on second ring. Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad. He said that when they started getting in so many worn LS7 heads, they had to reinvest in all new equipment to meet the demand and needs. He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves.
Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.
Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad. He said that when they started getting in so many worn LS7 heads, they had to reinvest in all new equipment to meet the demand and needs. He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves. Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set
But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
08-29-2012, 11:06 PM
#9
Burning Brakes
Those heads looked like they had been in a fire. Thank your lucky stars that you didn't get them.
So there may come a time when we might start seeing the same valve failures in the LS9.
Hopefully not, because that motor is a lot more expensive to replace even than an LS7.
I talked to him Monday last week, and he told me that these LS7 heads are keeping them very busy.
With all due respect to Antonio, all he says is that there was "no excessive play" between his valves and the guides. He does not mention actual measurements.
What are the measurements?
http://forums.corvetteforum.com/c6-z...n-an-09-a.html
I recall the post by hoefi listing .0037 as the service limit. but if it's .0025", as the poster in the above thread says that Katech told him, then I doubt that pure tactile sensation would allow most human beings to distinguish from .0025 to .0037 inches.
So there may come a time when we might start seeing the same valve failures in the LS9.
Hopefully not, because that motor is a lot more expensive to replace even than an LS7.
I talked to him Monday last week, and he told me that these LS7 heads are keeping them very busy.
With all due respect to Antonio, all he says is that there was "no excessive play" between his valves and the guides. He does not mention actual measurements.
What are the measurements?
http://forums.corvetteforum.com/c6-z...n-an-09-a.html
I recall the post by hoefi listing .0037 as the service limit. but if it's .0025", as the poster in the above thread says that Katech told him, then I doubt that pure tactile sensation would allow most human beings to distinguish from .0025 to .0037 inches.
08-29-2012, 11:20 PM
#11
Safety Car
Thread Starter
I mentioned Antonio as an example, there were other members as well as a local tuning shop with 10,000 miles on bronze guides and SS valves with in spec guides when he redid his heads (don't know why he redid them). Not all wear it seems. Or wear at the same rate.
08-29-2012, 11:59 PM
#12
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Those heads looked like they had been in a fire. Thank your lucky stars that you didn't get them.
So there may come a time when we might start seeing the same valve failures in the LS9.
Hopefully not, because that motor is a lot more expensive to replace even than an LS7.
I talked to him Monday last week, and he told me that these LS7 heads are keeping them very busy.
With all due respect to Antonio, all he says is that there was "no excessive play" between his valves and the guides. He does not mention actual measurements.
What are the measurements?
http://forums.corvetteforum.com/c6-z...n-an-09-a.html
I recall the post by hoefi listing .0037 as the service limit. but if it's .0025", as the poster in the above thread says that Katech told him, then I doubt that pure tactile sensation would allow most human beings to distinguish from .0025 to .0037 inches.
I don't know about you but I don't believe that I can "feel" the difference in terms of "excessive play" between say, .0037 inches and .0041 inches.
So there may come a time when we might start seeing the same valve failures in the LS9.
Hopefully not, because that motor is a lot more expensive to replace even than an LS7.
I talked to him Monday last week, and he told me that these LS7 heads are keeping them very busy.
With all due respect to Antonio, all he says is that there was "no excessive play" between his valves and the guides. He does not mention actual measurements.
What are the measurements?
http://forums.corvetteforum.com/c6-z...n-an-09-a.html
I recall the post by hoefi listing .0037 as the service limit. but if it's .0025", as the poster in the above thread says that Katech told him, then I doubt that pure tactile sensation would allow most human beings to distinguish from .0025 to .0037 inches.
I don't know about you but I don't believe that I can "feel" the difference in terms of "excessive play" between say, .0037 inches and .0041 inches.
Intake -
Production 0.001 to 0.0024 inches
Service 0.0037 inches
Exhaust -
Production 0.001 to 0.0026 inches
Service 0.0037 inches
08-30-2012, 01:51 AM
#14
Team Owner
DH
08-30-2012, 02:06 AM
#15
You have people in here reporting that they are out of spec in as little as 4,000 miles, and if you asked Richard what was the lowest number of miles he had seen on a set of heads which demonstrated excessive wear, I wonder what he would say.
Katech also reports seeing excessive valve guide wear on LS7s and LS9s.
16,000 street miles did this to Musicman's valve guides.
http://forums.corvetteforum.com/c6-z...post1581603283
So like you allude to, clearly some are wearing down and some are not, and there appears to be no solid rhyme nor reason yet as to why.
That would be impossible as you know quite well. I can feel .25 to .50 mm very easily and do on a daily basis. But .0004 inch (difference between above mentioned specs) which is .01 of a mm is impossible. Even the entire .0037 inch which is .09 of a mm would be very difficult to discern.
DH
DH
Even if he removed the springs, he might not perceive much if any lateral movement at all and could still be out of spec.
Attempting to wiggle his valves under spring tension????
OK.....
So what if they don't move? Just put the valve covers on and rest easy???
Last edited by '06 Quicksilver Z06; 09-03-2012 at 07:06 PM.
08-30-2012, 02:37 AM
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And that's part of why I said what I did last week with regard to the gentleman who removed his valve covers and gave his valves the "wiggle test" while they were still under spring tension.
Even if he removed the springs, he might not perceive much if any lateral movement at all and could still be out of spec.
Attempting to wiggle his valves under spring tension????
OK.....
So what if they don't move? Just put the valve covers on and rest easy???
Even if he removed the springs, he might not perceive much if any lateral movement at all and could still be out of spec.
Attempting to wiggle his valves under spring tension????
OK.....
So what if they don't move? Just put the valve covers on and rest easy???
there is about 112lbs on the valve head to the seat....
08-30-2012, 08:02 AM
#17
Thought Id share a quick conversation I had with Rich today from WCCH. I was looking at purchasing a set of used LS7 heads that would need some machine work. Didn't get them, they were sold to someone else, but this morning I decided to get a quote on what cost would be to make these like new again. As we were talking, mind you, I'm in FL and called at 9am. That's 6am in Cali. Answered on second ring. Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad. He said that when they started getting in so many worn LS7 heads, they had to reinvest in all new equipment to meet the demand and needs. He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves.
Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.
Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad. He said that when they started getting in so many worn LS7 heads, they had to reinvest in all new equipment to meet the demand and needs. He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves. Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set
But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
If it was a heat issue, you would think my car and Antonios would have out of spec guides as ours were driven hard, but that doesn't appear to be the case (with these two examples anyway).
Last edited by ConfusedGarage; 08-30-2012 at 08:04 AM.
08-30-2012, 09:34 AM
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08-30-2012, 09:48 AM
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Every component on a car wears, even the laser in your cd player. If this statement read "in spec" rather than "wear", it would be worded fairly. My heads were in spec at 20,000 hard miles. My car is not a waxer, I have well over 100 drag passes in it. I realize you were somewhat joking, but still trying to keep these threads fair I felt the need.
If it was a heat issue, you would think my car and Antonios would have out of spec guides as ours were driven hard, but that doesn't appear to be the case (with these two examples anyway).
If it was a heat issue, you would think my car and Antonios would have out of spec guides as ours were driven hard, but that doesn't appear to be the case (with these two examples anyway).
Bill
08-30-2012, 09:51 AM
#20
Melting Slicks
Thought Id share a quick conversation I had with Rich today from WCCH. I was looking at purchasing a set of used LS7 heads that would need some machine work. Didn't get them, they were sold to someone else, but this morning I decided to get a quote on what cost would be to make these like new again. As we were talking, mind you, I'm in FL and called at 9am. That's 6am in Cali. Answered on second ring. Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad. He said that when they started getting in so many worn LS7 heads, they had to reinvest in all new equipment to meet the demand and needs. He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves.
Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.
Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
Rich mentioned that before the LS7, their head restoration equipment was old. He said that WCCH really never got a set of heads with worn out guides. Heads would come in, dating back to the early 90s with tens of thousands of miles and guides that were in perfect shape. Before the LS7, the only guides they replaced were the occasional broken ones. Guide wear in the LS9 is just as bad. He said that when they started getting in so many worn LS7 heads, they had to reinvest in all new equipment to meet the demand and needs. He mentioned the need to tumble polish the intake valves which he said the guides were also showing wear on that side. Just thought Id share that tid bit of info.... Thought it was interesting. Of course, there is still competing theories of QA problems VS. heat transfer issues or too good of heat transfer by the sodium valves. Antonio1988 just posted up how his heads were perfect with just normal wear on the guides after 27,000 hard miles. Makes you wonder....heat transfer in his case was obviously not an issue...
I asked Rich if he had seen a set of good LS7 heads with no guide wear, he said, yes, a new set
But in all seriousness, Antonio1988s heads, if true that they were in spec (my phrasing not his), would help to move this topic forward. We need more members pulling their heads...if only there was an easy way to check the guides without 10 hrs labor.Edit: Rich also said that bronze guides will wear just as bad...we all know he recommends SS valves and said the have excellent thermodynamic characteristics...this, like I said is a competing theory with the sodium valves.
Did he happen to mention the 2009 Z06 heads are fixed and there isnt any wear on those?
