[Z06] What should it Cost?
07-24-2014, 11:46 PM
#21
Melting Slicks
Not much info on anyone that's had any head modifications done over the long term. I'm curious to hear how long "a while back" actually is in time and mileage. As well as any additional modifications to the car such as a cam or anything else. We also know that the original machining specs from them were a little larger than the most current specs so that could be significant.
I'd love to see data on ANY head work in the long term, AH included.
I'd love to see data on ANY head work in the long term, AH included.
As we know there is very little long term results from WCCH. I am curious as well what "a while back" is. Most likely not that long ago.
Regardless a WCCH head addressed with the SS modification coming back out of spec is not good at all. Mods would play a role I am sure but that goes back to other discussions on this forum and my feeling as well on how bronze guides being a softer metal may not be the best choice for the 1.8 rocker due to side load which would lead to guide wear. Mods or not bronze still might not be the best replacement.
Aside from that.. where there is smoke there is fire. Most have not reinspected or do not have enough on this mod to say "everything is fine" if this car has 50K miles and was stock and out of spec that would not be a good sign or proof of longevity and those who are running this modification would be justified being concerned.
Last edited by propain; 07-24-2014 at 11:48 PM.
07-24-2014, 11:56 PM
#22
Le Mans Master
............or buy aftermarket PRC 265 heads, $3300, then sell you oems for $800 or so.............great head and no down time
07-25-2014, 01:22 AM
#23
Team Owner
How many miles on your new R&R to claim all is good? Do you think your set up will fair better than the WCCH that you say were out of spec after the same usage?
Does this car belong to a forum member?
You should call Richard and tell him what you found. I'm sure he would like to know. My WCCH SS valve/Bronze guide heads had 25K miles and over 12 track days but easily passed the wiggle test by a top GM Corvette specialist.
I'm not condeming these new valves or PM guides but I would like to see some results from this new setup. Especially some that are driven hard on the track.
DH
07-25-2014, 01:25 AM
#24
Team Owner
Well they checked the heads and said they were ok at the time, but there is no telling what could happen after a few more thousand they have seen no set pattern of when they go... It already had the G7X3 cam in it.
I asked about going aftermarket heads, but they said it was a overkill for for my set up, they could do it if I wanted. So I did what they recommend and had the heads redone with their LG Motorsports prepared LS7 cylinder head package, Includes both heads, valves, dual springs, and titanium retainers. (Just reading off the receipt) Not sure of all the exact specs (trust their opinion). I did have them add FAST Intake/Fuel rails and 102 Throttle body since they had to take them off anyways, kind of like getting free labor. Got 560 at the wheels
There was full exhaust on her already as well. Now getting ready to order the brake duct kit from them
I asked about going aftermarket heads, but they said it was a overkill for for my set up, they could do it if I wanted. So I did what they recommend and had the heads redone with their LG Motorsports prepared LS7 cylinder head package, Includes both heads, valves, dual springs, and titanium retainers. (Just reading off the receipt) Not sure of all the exact specs (trust their opinion). I did have them add FAST Intake/Fuel rails and 102 Throttle body since they had to take them off anyways, kind of like getting free labor. Got 560 at the wheels
There was full exhaust on her already as well. Now getting ready to order the brake duct kit from them Your setup sounds awesome and LG is a top notch outfit and also supports our local Corvette Challenge
DH
07-25-2014, 01:31 AM
#25
Team Owner
Actually, I think might trust you more 
..... 
DH
07-25-2014, 01:32 AM
#26
Team Owner
Not much info on anyone that's had any head modifications done over the long term. I'm curious to hear how long "a while back" actually is in time and mileage. As well as any additional modifications to the car such as a cam or anything else. We also know that the original machining specs from them were a little larger than the most current specs so that could be significant.
I'd love to see data on ANY head work in the long term, AH included.
I'd love to see data on ANY head work in the long term, AH included.
DH
07-25-2014, 02:04 AM
#27
What constitues a "while back"? How many miles? What kind of usage?What kind of cam?
How many miles on your new R&R to claim all is good? Do you think your set up will fair better than the WCCH that you say were out of spec after the same usage?
Does this car belong to a forum member?
You should call Richard and tell him what you found. I'm sure he would like to know. My WCCH SS valve/Bronze guide heads had 25K miles and over 12 track days but easily passed the wiggle test by a top GM Corvette specialist.
I'm not condeming these new valves or PM guides but I would like to see some results from this new setup. Especially some that are driven hard on the track.
DH
How many miles on your new R&R to claim all is good? Do you think your set up will fair better than the WCCH that you say were out of spec after the same usage?
Does this car belong to a forum member?
You should call Richard and tell him what you found. I'm sure he would like to know. My WCCH SS valve/Bronze guide heads had 25K miles and over 12 track days but easily passed the wiggle test by a top GM Corvette specialist.
I'm not condeming these new valves or PM guides but I would like to see some results from this new setup. Especially some that are driven hard on the track.
DH
Not much info on anyone that's had any head modifications done over the long term. I'm curious to hear how long "a while back" actually is in time and mileage. As well as any additional modifications to the car such as a cam or anything else. We also know that the original machining specs from them were a little larger than the most current specs so that could be significant.
I'd love to see data on ANY head work in the long term, AH included.
I'd love to see data on ANY head work in the long term, AH included.
The first mention of one of the recent alternative setups that we see discussed on this forum as of late, and that I have been able to find, dates back about 8 months
http://forums.corvetteforum.com/c6-z...d-special.html
So in terms of long term, I'd like to see more examples of alternative setups, including this one, as well.
However since Hib Halverson wrote the following posts, it indicated to me right away that "valvetrain weight" just might not the be all and end all, and using a valve with what Hib claims is the "worst" in terms of heat transfer capabilities of all available aftermarket choices, doesn't seem to me to be any "better" of an idea, and the way I look at it, might be an even worse idea, than using a "heavier" SS valve to address the issue were I in a decision making process on managing the issue.
LS7 exhaust choices are:
stock, hollow stem, sodium-filled
hollow stem, air-filled
sold SS
Inconel
titanium.
The worst choice, IMO, is a "air-filled", hollow-stem valve.
Why?
Air is a terrible conductor of heat. You gun drill the stem and do nothing else, you now have a valve with a head which will run much hotter than the stock valve head because 1) the heat path: valve head > stem > guide > head > coolant is now severely restricted and 2) the heat path: valve head > seat > head > coolant cannot carry the extra thermal load.....
stock, hollow stem, sodium-filled
hollow stem, air-filled
sold SS
Inconel
titanium.
The worst choice, IMO, is a "air-filled", hollow-stem valve.
Why?
Air is a terrible conductor of heat. You gun drill the stem and do nothing else, you now have a valve with a head which will run much hotter than the stock valve head because 1) the heat path: valve head > stem > guide > head > coolant is now severely restricted and 2) the heat path: valve head > seat > head > coolant cannot carry the extra thermal load.....
....
Another issue I question about hollow-stem valves with no sodium in them. Whether the valve stem is metal, hollow-with-no-sodium or hollow-with-sodium filling, the stem is still the heat path from the valve head to the guide, to the head and then to the coolant.
With an "unfilled" or "dry" hollow stem valve, you replace metal with air which is a very poor conductor of heat compared to metal, so without sodium in the hollow stem, what are you doing to prevent the valve head from overheating?
Another issue I question about hollow-stem valves with no sodium in them. Whether the valve stem is metal, hollow-with-no-sodium or hollow-with-sodium filling, the stem is still the heat path from the valve head to the guide, to the head and then to the coolant.
With an "unfilled" or "dry" hollow stem valve, you replace metal with air which is a very poor conductor of heat compared to metal, so without sodium in the hollow stem, what are you doing to prevent the valve head from overheating?
http://forums.corvetteforum.com/c6-z...post1582632612
Actually we have been changing them in the cars since approx Sept/October of 2005 when we did Tim Kerrigan of Red Line Engine Oil's 2006 Z06.
During the first cam package Z06 cars we did here, all of them received head work, One piece Ti intake valves (no lash cap), and stainless exhaust valves. We actually had to purchase around 150 intake valves to have them made as it was a new item at the time.
So if you had one of our first 100 or so H/C Z06's all of the guides and both valves were replaced. A lot of the early cars also had a replacement piston due to worries about them pulling the wrist pin out of the bottom of the piston at high RPM (this coming from Tim at Red Line).
I will say this, all of the above cars, to my knowledge, are all still currently running and doing so both fine on the street and race track. These cars were done this way to increase valve train stability and worry about loosing lash caps during over-rev conditions plus increasing exhaust flow with a better valve. At that time, no one had seen one break.
While we have done a number of cam kits w/o valve replacement and have been fine (my neighbors Z is almost at 100k with stock heads) most of them have had some degree of head work.
During the first cam package Z06 cars we did here, all of them received head work, One piece Ti intake valves (no lash cap), and stainless exhaust valves. We actually had to purchase around 150 intake valves to have them made as it was a new item at the time.
So if you had one of our first 100 or so H/C Z06's all of the guides and both valves were replaced. A lot of the early cars also had a replacement piston due to worries about them pulling the wrist pin out of the bottom of the piston at high RPM (this coming from Tim at Red Line).
I will say this, all of the above cars, to my knowledge, are all still currently running and doing so both fine on the street and race track. These cars were done this way to increase valve train stability and worry about loosing lash caps during over-rev conditions plus increasing exhaust flow with a better valve. At that time, no one had seen one break.
While we have done a number of cam kits w/o valve replacement and have been fine (my neighbors Z is almost at 100k with stock heads) most of them have had some degree of head work.
http://forums.corvetteforum.com/auto...e-package.html
Last edited by '06 Quicksilver Z06; 07-25-2014 at 02:51 AM.
07-25-2014, 09:44 AM
#28
As of yet there is still no known magic bullet.
07-25-2014, 09:54 AM
#29
This character assassination routine against anyone who has a factual discouraging word is really getting old . . . . .
07-25-2014, 10:16 AM
#30
Melting Slicks
Why would my interpretation be biased? I am pretty consistent. I am simply looking for facts. If AH says they inspected a head and it was from WCCH with bronze/ss and it was out of spec I believe them. Why wouldn't I believe them?
07-25-2014, 10:23 AM
#31
Racer
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I would advise you to send them into us for reworking.
Our most popular package which contains Hollow Ferrea vales and aftermarket HARDENED PM guides starts at only $1,228 (plus return shipping)
We also have 2 core sets avaliable and ready to ship out (with a refundable core deposit)
We have been reworking 3-4+ sets a week for a few months now.
Support your corvetteforum.com vendors!!!!
http://www.americanheritageperformance.com/Contact.html
Search on here about our heads, lots of people running them and all satisfied customers.
PS...
I would higly advise against running a 98+ gram heavy stolid stainless steel valve. The LS7 valve train was designed to be light. It was engendered this way for a reason. Some company's love to throw a heavy heavy SS valve in put bronze guide in and call it good... why? Because that's they way it used to work years and years ago. Technology has improved drastically since then. Some people refuse to change and accept advancements. Powder metal is used by the manufacture for a reason (longevity). We use a hardened aftermarket PM guide that is superior to the GM oem Pm guide and the bronze guides used by many competitors.
what ever you do keep your LS7 valve train as light as possible.
We recently had a Z in the shop that had heads that were reworked by wcch a while back, had bronze and heavy ss valves. it was out of spec. We R&R'd the heads, put our package 4 heads on and all was good.
Our most popular package which contains Hollow Ferrea vales and aftermarket HARDENED PM guides starts at only $1,228 (plus return shipping)
We also have 2 core sets avaliable and ready to ship out (with a refundable core deposit)
We have been reworking 3-4+ sets a week for a few months now.
Support your corvetteforum.com vendors!!!!
http://www.americanheritageperformance.com/Contact.html
Search on here about our heads, lots of people running them and all satisfied customers.
PS...
I would higly advise against running a 98+ gram heavy stolid stainless steel valve. The LS7 valve train was designed to be light. It was engendered this way for a reason. Some company's love to throw a heavy heavy SS valve in put bronze guide in and call it good... why? Because that's they way it used to work years and years ago. Technology has improved drastically since then. Some people refuse to change and accept advancements. Powder metal is used by the manufacture for a reason (longevity). We use a hardened aftermarket PM guide that is superior to the GM oem Pm guide and the bronze guides used by many competitors.
what ever you do keep your LS7 valve train as light as possible.
We recently had a Z in the shop that had heads that were reworked by wcch a while back, had bronze and heavy ss valves. it was out of spec. We R&R'd the heads, put our package 4 heads on and all was good.
07-25-2014, 10:28 AM
#32
Over the last few months, there have been a few contributions made to the knowledge base regarding the LS7 valve and valve train related issues.
AH indicates a couple of discoveries during their observations and experiences in the management of this issue.
The one which stands out to me is their report of inconsistent and varying wall thickness in the stock hollow stemmed exhaust valve in their examinations of the stock exhaust valves.
AH indicates a couple of discoveries during their observations and experiences in the management of this issue.
The one which stands out to me is their report of inconsistent and varying wall thickness in the stock hollow stemmed exhaust valve in their examinations of the stock exhaust valves.
Last edited by '06 Quicksilver Z06; 07-25-2014 at 10:30 AM.
07-25-2014, 10:36 AM
#33
We're all in this together and its really unbelievable how every one of these conversations turns into BS.
Lets just wait for AH to bring some more info for us. I'm looking forward to it and it will be a service to the forum. If they don't provide more info then I'll have to dismiss the comment as unsubstantiated, though I have no reason to believe they won't be able to provide us with at least:
(1) a list of mods
(2) when the heads were serviced by wcch
(3) miles on the heads since being done
(4) parts used in the heads
(5) guide clearance measurements
07-25-2014, 10:41 AM
#34
I'm not arguing with you AT ALL!!!! But can you explain or show me something that says the PM guides you use are really that much better than bronze? I'm seriously just trying to make an educated decision on this. I'm in the midst of getting ready to have a set of heads re-worked and I find what you said about the PM guides very interesting. Meaning, it makes sense that PM guides would last longer but, I always like to know why when I can. [...]
The PM guides are harder than the bronze guides. That alone should mean that they will last longer and stand up to more abuse (like side loading of the valve stem).
However, it seems that once PM starts to wear it contaminates itself (little bits of PM acting like sandpaper) and then the wear accelerates rapidly, unlike a bronze guide.
So one goal is a PM guide that doesn't experience the initial wear that is probably making the stock PM guides go bad. But we don't really know what is causing that initial wear. Earlier Chevy engines with PM guides have been reported with hundreds of thousands of mile with essentially no guide wear at all, so the LS7 deal is a mystery.
Heat transfer capabilities aside, the PM guide should be the longest life guide (and has proven itself so in the past in other engines) -- if that initial wear deal can be eliminated (which could be bad machining or lubrication/heat related). If it is side load that is causing the wear, and if that side load is inherent in the LS7 design and not a result of some machining/assembly/lubrication error/shortcoming, then neither guide is probably going to last long (say, up to 50K miles). Without formal long term testing/inspection it will remain a mystery, so all you can do is make your best guess.
The bronze guide doesn't seem to have these self-contaminating issues and should be a better conductor of heat (quite possibly important on the exhaust side). However, it can normally expected to wear out quicker than a properly-functioning PM guide. Now if it makes it to 50K or 75K miles then that shorter life is probably enough for most sports car owners, but it appears that in a few instances it is not going to make it that far. Again, we don't know exactly why (valve stem side load would seem to be the most likely culprit, and that may not be something that can be corrected without extensive modification like roller tipped rockers).
.
Last edited by Mark2009; 07-25-2014 at 10:46 AM. Reason: added last para.
07-25-2014, 10:55 AM
#35
Melting Slicks
I don't think you're bias and I believe AH. We just all need some more info before this turns into a war between those that think WCCH has released minions on the forum, those that live and breath WCCH, and those of us in between that have no allegiances and only want the facts.
We're all in this together and its really unbelievable how every one of these conversations turns into BS.
Lets just wait for AH to bring some more info for us. I'm looking forward to it and it will be a service to the forum. If they don't provide more info then I'll have to dismiss the comment as unsubstantiated, though I have no reason to believe they won't be able to provide us with at least:
(1) a list of mods
(2) when the heads were serviced by wcch
(3) miles on the heads since being done
(4) parts used in the heads
(5) guide clearance measurements
We're all in this together and its really unbelievable how every one of these conversations turns into BS.
Lets just wait for AH to bring some more info for us. I'm looking forward to it and it will be a service to the forum. If they don't provide more info then I'll have to dismiss the comment as unsubstantiated, though I have no reason to believe they won't be able to provide us with at least:
(1) a list of mods
(2) when the heads were serviced by wcch
(3) miles on the heads since being done
(4) parts used in the heads
(5) guide clearance measurements
I agree and I want more facts.
But yes, its sad isn't it? I made one post and we have already received a flurry of posts defending SS valves and accusations of me being biased or AH having an agenda. Some have even gone steps above to attack OEM valves when they aren't even being discussed or Ferrea hollow valves when they aren't part of the conversation either. The gloves sure did come off fast in this one.
When it came to AH's statement that the OEM valves have inconsistent wall thickness that was taken as gospel. But now that they have inspected a SS/Bronze WCCH head and found it to be out of spec we receive a flurry of attacks from the usual suspects. Please understand I am not lumping you into that category I am simply making an observation.
If they do not offer more info than I agree it would be unsubstantiated. Its only fair to expect that all sides play by the same rules in this matter. Inconsistent wall thickness in OEM valves observed by AH was never substantiated either yet it appears to be accepted by some at hard evidence. HIBS opinions on the hollow valves lacking sodium having possible heat issues have also not be substantiated yet they are quoted ad infinitum.
I think your list of 1 through 5 are all fair questions and I would like to see them answered as well. Instead of blind attacks and people trying to plug leaks before they even open up how about we just wait for those questions to be answered.
Last edited by propain; 07-25-2014 at 10:57 AM.
07-25-2014, 10:56 AM
#36
In general terms...
The PM guides are harder than the bronze guides. That alone should mean that they will last longer and stand up to more abuse (like side loading of the valve stem).
However, it seems that once PM starts to wear it contaminates itself (little bits of PM acting like sandpaper) and then the wear accelerates rapidly, unlike a bronze guide.
So one goal is a PM guide that doesn't experience the initial wear that is probably making the stock PM guides go bad. But we don't really know what is causing that initial wear. Earlier Chevy engines with PM guides have been reported with hundreds of thousands of mile with essentially no guide wear at all, so the LS7 deal is a mystery.
Heat transfer capabilities aside, the PM guide should be the longest life guide (and has proven itself so in the past in other engines) -- if that initial wear deal can be eliminated (which could be bad machining or lubrication/heat related). If it is side load that is causing the wear, and if that side load is inherent in the LS7 design and not a result of some machining/assembly/lubrication error/shortcoming, then neither guide is probably going to last long (say, up to 50K miles). Without formal long term testing/inspection it will remain a mystery, so all you can do is make your best guess.
The bronze guide doesn't seem to have these self-contaminating issues and should be a better conductor of heat (quite possibly important on the exhaust side). However, it can normally expected to wear out quicker than a properly-functioning PM guide. Now if it makes it to 50K or 75K miles then that shorter life is probably enough for most sports car owners, but it appears that in a few instances it is not going to make it that far. Again, we don't know exactly why (valve stem side load would seem to be the most likely culprit, and that may not be something that can be corrected without extensive modification like roller tipped rockers).
.
The PM guides are harder than the bronze guides. That alone should mean that they will last longer and stand up to more abuse (like side loading of the valve stem).
However, it seems that once PM starts to wear it contaminates itself (little bits of PM acting like sandpaper) and then the wear accelerates rapidly, unlike a bronze guide.
So one goal is a PM guide that doesn't experience the initial wear that is probably making the stock PM guides go bad. But we don't really know what is causing that initial wear. Earlier Chevy engines with PM guides have been reported with hundreds of thousands of mile with essentially no guide wear at all, so the LS7 deal is a mystery.
Heat transfer capabilities aside, the PM guide should be the longest life guide (and has proven itself so in the past in other engines) -- if that initial wear deal can be eliminated (which could be bad machining or lubrication/heat related). If it is side load that is causing the wear, and if that side load is inherent in the LS7 design and not a result of some machining/assembly/lubrication error/shortcoming, then neither guide is probably going to last long (say, up to 50K miles). Without formal long term testing/inspection it will remain a mystery, so all you can do is make your best guess.
The bronze guide doesn't seem to have these self-contaminating issues and should be a better conductor of heat (quite possibly important on the exhaust side). However, it can normally expected to wear out quicker than a properly-functioning PM guide. Now if it makes it to 50K or 75K miles then that shorter life is probably enough for most sports car owners, but it appears that in a few instances it is not going to make it that far. Again, we don't know exactly why (valve stem side load would seem to be the most likely culprit, and that may not be something that can be corrected without extensive modification like roller tipped rockers).
.
Good explanation
07-25-2014, 10:58 AM
#37
I agree and I want more facts.
But yes, its sad isn't it? I made one post and we have already received a flurry of posts defending SS valves and accusations of me being biased or AH having an agenda. Some have even gone steps above to attack OEM valves when they aren't even being discussed or Ferrea hollow valves when they aren't part of the conversation either. The gloves sure did come off fast in this one.
When it came to AH's statement that the OEM valves have inconsistent wall thickness that was taken as gospel. But now that they have inspected a SS/Bronze WCCH head and found it to be out of spec we receive a flurry of attacks from the usual suspects. Please understand I am not lumping you into that category I am simply making an observation.
If they do not offer more info than I agree it would be unsubstantiated. Its only fair to expect that all sides play by the same rules in this matter. Inconsistent wall thickness in OEM valves observed by AH was never substantiated either yet it appears to be accepted by some at hard evidence. HIBS opinions on the hollow valves lacking sodium have also not be substantiated yet they are quoted ad infinitum.
I think your list of 1 through 5 are all fair questions and I would like to see them answered as well. Instead of blind attacks and people trying to plug leaks before they even open up how about we just wait for those questions to be answered.
But yes, its sad isn't it? I made one post and we have already received a flurry of posts defending SS valves and accusations of me being biased or AH having an agenda. Some have even gone steps above to attack OEM valves when they aren't even being discussed or Ferrea hollow valves when they aren't part of the conversation either. The gloves sure did come off fast in this one.
When it came to AH's statement that the OEM valves have inconsistent wall thickness that was taken as gospel. But now that they have inspected a SS/Bronze WCCH head and found it to be out of spec we receive a flurry of attacks from the usual suspects. Please understand I am not lumping you into that category I am simply making an observation.
If they do not offer more info than I agree it would be unsubstantiated. Its only fair to expect that all sides play by the same rules in this matter. Inconsistent wall thickness in OEM valves observed by AH was never substantiated either yet it appears to be accepted by some at hard evidence. HIBS opinions on the hollow valves lacking sodium have also not be substantiated yet they are quoted ad infinitum.
I think your list of 1 through 5 are all fair questions and I would like to see them answered as well. Instead of blind attacks and people trying to plug leaks before they even open up how about we just wait for those questions to be answered.
07-25-2014, 11:55 AM
#38
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The vehicle had headers only, no cam. The vehicle was brought into the shop by the new owner as a post purchase inspection. He was told when he purchased the car that the heads were rebuilt around 20,000 miles ago. I have no idea how the previous owner drove the vehicle (road, track, canyon runs, daily driving, ect...) or even if they were truly rebuilt 20,000 miles ago (sometimes when selling a car the seller doesn't tell the complete truth). We just did a wiggle test before removing and reworking the heads. Heads had bronze guides dual springs and SS exh valves. Most of the exhausts were right on the border of spec but two were substantially out of spec on the wiggle test (.0095" was the worst of the wiggle test results). Off the top of my head if I remember correctly it was the #5 and #6 exh valves that were the most out of spec.
I will try to find the full wiggle test result sheet for this customer and post it. The vehicle was in our shop 4 months ago.
I will try to find the full wiggle test result sheet for this customer and post it. The vehicle was in our shop 4 months ago.
Last edited by American Heritage; 07-25-2014 at 12:29 PM. Reason: wording
07-25-2014, 12:10 PM
#39
Melting Slicks
The vehicle had headers only, no cam. The vehicle was brought into the shop by the new owner as a post purchase inspection. He was told when he purchased the car that the heads were rebuilt around 20,000 miles ago. I have no idea how the previous owner drove the vehicle (road, track, canyon runs, daily driving, ect...)
As to the rest don't let these guys get to you. That is what they want. Just stick to the facts and stay professional. Personally I would edit that part out of my post if I were you.
07-25-2014, 12:31 PM
#40
Melting Slicks
The vehicle had headers only, no cam. The vehicle was brought into the shop by the new owner as a post purchase inspection. He was told when he purchased the car that the heads were rebuilt around 20,000 miles ago. I have no idea how the previous owner drove the vehicle (road, track, canyon runs, daily driving, ect...) or even if they were truly rebuilt 20,000 miles ago (sometimes when selling a car the seller doesn't tell the complete truth). We just did a wiggle test before removing and reworking the heads. Heads had bronze guides dual springs and SS exh valves. Most of the exhausts were right on the border of spec but two were substantially out of spec on the wiggle test (.0095" was the worst of the wiggle test results). Off the top of my head if I remember correctly it was the #5 and #6 exh valves that were the most out of spec.
I will try to find the full wiggle test result sheet for this customer and post it. The vehicle was in our shop 4 months ago.
I will try to find the full wiggle test result sheet for this customer and post it. The vehicle was in our shop 4 months ago.
Thanks again for the details. Yes the results would go a long way on this forum. You know how it goes around here. As well were the heads stamped with WCCH?
