[Z06] The "Out of Spec" Guide Wear Registry
#521
Burning Brakes
Hello Shane,
Bellow are your "Raw" wiggle test results:
As follows:
1 int .009"
1exh .005"
3 int .007"
3exh .004"
5 int .007"
5exh .0035"
7 int .007"
7 exh.0045"
2 int .008"
2exh .004"
4 int .0095"
4exh .004"
6 int .011"
6exh .004"
8 int .011"
8exh .0035"
We have found that the actual dial bore gauge and mic measurements are roughly half of the raw wiggle test measurements. This means that any wiggle test measurement that is .008" is at the very end of the in tolerance spec and anything .009" or over is out of spec.
Here is my email from AHP.
2011 Z06 with 10k miles. Glad I went ahead and did the swap.
Bellow are your "Raw" wiggle test results:
As follows:
1 int .009"
1exh .005"
3 int .007"
3exh .004"
5 int .007"
5exh .0035"
7 int .007"
7 exh.0045"
2 int .008"
2exh .004"
4 int .0095"
4exh .004"
6 int .011"
6exh .004"
8 int .011"
8exh .0035"
We have found that the actual dial bore gauge and mic measurements are roughly half of the raw wiggle test measurements. This means that any wiggle test measurement that is .008" is at the very end of the in tolerance spec and anything .009" or over is out of spec.
Here is my email from AHP.
2011 Z06 with 10k miles. Glad I went ahead and did the swap.
#522
Instructor
Just got my results back from Kohle and here is what he found.
1 int .016"
1exh .011"
3 int .025"
3exh .013"
5 int .030"
5exh .011"
7 int .016"
7exh .012"
2 int .015"
2exh .009"
4 int .020"
4exh .010"
6 int .026"
6exh .009"
8 int .015"
8exh .009"
Summary:
This is one of the worst wiggle test we have seen in a while. We have seen much worse before but yours were in intimidate danger of failure. In fact with those large of clearances I would not be surprised to learn that you were having random misfire issues.
I am so glad I got these done. The car is a 2009 z06 with about 95,000 miles on it. I purchased it to restore from copart in december. When I got it home the car had a misfire on cylinder 5 and a random cylinder misfire. I still havnt driven the car and let it idle on the lift. I tried everything plugs, fuel injector coil pack ect. then I did a compression test and got big varying results on cylinder 5 you could here it have compression on some strokes and no compression on others. I was going to take it and get it aligned but instead decided to pull the heads right there and get them done. Im glad I did.
I found the phone number of the previous owner and learned that he put about 40k miles on it in about two years driving cross country. He was an older guy and didnt race it or track it. I had american heritage performance do the heads. did an awesome job. I just about have everything back together and will fire it up.
Thanks
1 int .016"
1exh .011"
3 int .025"
3exh .013"
5 int .030"
5exh .011"
7 int .016"
7exh .012"
2 int .015"
2exh .009"
4 int .020"
4exh .010"
6 int .026"
6exh .009"
8 int .015"
8exh .009"
Summary:
This is one of the worst wiggle test we have seen in a while. We have seen much worse before but yours were in intimidate danger of failure. In fact with those large of clearances I would not be surprised to learn that you were having random misfire issues.
I am so glad I got these done. The car is a 2009 z06 with about 95,000 miles on it. I purchased it to restore from copart in december. When I got it home the car had a misfire on cylinder 5 and a random cylinder misfire. I still havnt driven the car and let it idle on the lift. I tried everything plugs, fuel injector coil pack ect. then I did a compression test and got big varying results on cylinder 5 you could here it have compression on some strokes and no compression on others. I was going to take it and get it aligned but instead decided to pull the heads right there and get them done. Im glad I did.
I found the phone number of the previous owner and learned that he put about 40k miles on it in about two years driving cross country. He was an older guy and didnt race it or track it. I had american heritage performance do the heads. did an awesome job. I just about have everything back together and will fire it up.
Thanks
The following users liked this post:
Landru (05-11-2018)
#523
I don't have the numbers on mine, but my machinist said they were the worst he has ever seen!!
2013 427 Vert.
14k miles
Oh, zero mods before inspection.
2013 427 Vert.
14k miles
Oh, zero mods before inspection.
Last edited by S.U. Vette; 05-11-2018 at 12:06 AM.
#524
Burning Brakes
2009 Z06 - 9,800 miles - ALL INTAKE, MOST EXHAUST VALVES OUT OF SPEC
Okay, here's mine.
2009 Z06, 9,800 miles on it. As I am the 3rd owner, I managed to contact the 2nd (previous) owner, and he said he hardly drove it and never raced it, etc. I believe he said the 1st original owner was an older gentleman, who also hardly drove it. Safe to say that based on that and the immaculate condition the car is in, I don't think it was ever driven hard.
I did a hand wiggle before I sent the heads to Kohle and took video, which I will be publishing when I can. So, here we go...
Per Kohle's "raw" wiggle test results:
UPDATED: Here's a video of me doing the wiggle test by hand:
It is absolutely pathetic that a vehicle with a hand-built engine and a $70k sticker price that has been babied its entire life with less than 10,000 miles on it was already heading for self-cannibalization. I have been a GM supporter and customer my entire driving life and it is absurd that they have denied the fact that this is an issue. A few folks at GM should be embarrassed and ashamed.
2009 Z06, 9,800 miles on it. As I am the 3rd owner, I managed to contact the 2nd (previous) owner, and he said he hardly drove it and never raced it, etc. I believe he said the 1st original owner was an older gentleman, who also hardly drove it. Safe to say that based on that and the immaculate condition the car is in, I don't think it was ever driven hard.
I did a hand wiggle before I sent the heads to Kohle and took video, which I will be publishing when I can. So, here we go...
Per Kohle's "raw" wiggle test results:
We have found that the raw wiggle test results are roughly half of what the actual dial bore and mic measurements are. This means that any raw wiggle test results .008" are at the very end of the service spec and any raw wiggle test measurement .009" or over are out of spec.
As follows:
1 int .012"
1 exh .010"
3 int .014"
3 exh .008"
5 int .013"
5 exh .009"
7 int .016"
7 exh .009"
2 int .013"
2 exh .008"
4 int .011"
4 exh .008"
6 int .013"
6 exh .008"
8 int .010"
8 exh .008"
Going by the results it looks like every single intake valve was out of spec with most the exhaust also being out of spec. Its a good things you decided to rework your heads.
As follows:
1 int .012"
1 exh .010"
3 int .014"
3 exh .008"
5 int .013"
5 exh .009"
7 int .016"
7 exh .009"
2 int .013"
2 exh .008"
4 int .011"
4 exh .008"
6 int .013"
6 exh .008"
8 int .010"
8 exh .008"
Going by the results it looks like every single intake valve was out of spec with most the exhaust also being out of spec. Its a good things you decided to rework your heads.
It is absolutely pathetic that a vehicle with a hand-built engine and a $70k sticker price that has been babied its entire life with less than 10,000 miles on it was already heading for self-cannibalization. I have been a GM supporter and customer my entire driving life and it is absurd that they have denied the fact that this is an issue. A few folks at GM should be embarrassed and ashamed.
Last edited by JDebler; 05-17-2018 at 09:29 AM.
#525
Burning Brakes
I purchased AHP Heads for my 2007 Z06. Car has 17,500 miles, engine was replaced at 7332 miles. So current engine has 10,000 miles. Below are the test results for my old heads
Bellow are your Raw wiggle test results. We have found that the acutal dial bore and mic measurment are roughly half of what the raw wiggle test reasults are. This means any raw wiggle test .008" is at the very end of the spec and anything .009" or over is out of spec.
As follows:
1 int .006"
1exh .005"
3 int .008"
3exh .005"
5 int .0085"
5exh .0055"
7 int .008"
7exh .006"
2 int .0065"
2exh .005"
4 int .008"
4exh .006"
6 int .0085"
6exh .005"
8 int .007"
8exh .005"
I had 5 valves near end of spec. and only 10,000 miles on this engine.
Phil
Bellow are your Raw wiggle test results. We have found that the acutal dial bore and mic measurment are roughly half of what the raw wiggle test reasults are. This means any raw wiggle test .008" is at the very end of the spec and anything .009" or over is out of spec.
As follows:
1 int .006"
1exh .005"
3 int .008"
3exh .005"
5 int .0085"
5exh .0055"
7 int .008"
7exh .006"
2 int .0065"
2exh .005"
4 int .008"
4exh .006"
6 int .0085"
6exh .005"
8 int .007"
8exh .005"
I had 5 valves near end of spec. and only 10,000 miles on this engine.
Phil