Newbie with LS7 Questions - Page 6 - CorvetteForum - Chevrolet Corvette Forum Discussion



C6 Corvette ZR1 & Z06
General info about GMs Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track

Newbie with LS7 Questions

Reply
 
 
 
Thread Tools Search this Thread
Old 06-25-2017, 12:09 AM   #101
rockinSeat
CF Senior Member
 
rockinSeat's Avatar
 
Member Since: May 2008
Location: Colorado Springs Colorado
Posts: 659
Thanks: 0
Thanked 6 Times in 6 Posts
Default

I did a statistical analysis once (see my prior posts). It was something like, with 30,000 z06s as a population, to get within +/- 10% accuracy we need a sample size of like 4 or 5 hundred cars. So if you look at the out of spec registry thread below, and it's sister thread the in-spec registry, there were 200 out of spec and about 25 in spec.

So my statistics are a bit rusty, but I think I could say with about 100 percent confidence that at least half of them are f'd up.

also, there was a helpful member here who used to keep a record of all the ls7 failures, see his old posts. He had about 35 dropped valve cases documented in his spreadsheet. That was years ago.

Another statistical analysis I did was on the mileage distribution...I concluded that the z06 population was not accumulating mileage very fast, in fact we wouldn't see most failures for years.

Guess what? Gm concluded the same thing. They'll be out of warranty before they pop, so as long as nobody spins into a semi on the interstate, we don't have to do a recall. Lol there have been two fires posted due to dropped valves with pictures.

So believe it or not, 6.5 failures per thousand may have been a true statement at one point in time, say, when the vast majority of all the ls7 had less than 20k miles. But what will the failure rate be when they've all had a 100k miles?

Hopefully it will be a lot lower because of people being proactive on this forum.


https://www.corvetteforum.com/forums/c6-corvette-zr1-and-z06/3386141-the-out-of-spec-guide-wear-registry.html

https://www.corvetteforum.com/forums/c6-corvette-zr1-and-z06/3385533-the-in-spec-guide-wear-registry.html
rockinSeat is offline   Reply With Quote
The Following User Says Thank You to rockinSeat For This Useful Post:
MTPZ06 (Yesterday)
Old 06-25-2017, 12:19 AM   #102
Dirty Howie
CF Senior Member
 
Dirty Howie's Avatar
 
Member Since: May 2004
Posts: 25,262
Thanked 88 Times in 64 Posts
Default

Quote:
Originally Posted by rockinSeat View Post
I did a statistical analysis once (see my prior posts). It was something like, with 30,000 z06s as a population, to get within +/- 10% accuracy we need a sample size of like 4 or 5 hundred cars. So if you look at the out of spec registry thread below, and it's sister thread the in-spec registry, there were 200 out of spec and about 25 in spec.

So my statistics are a bit rusty, but I think I could say with about 100 percent confidence that at least half of them are f'd up.

also, there was a helpful member here who used to keep a record of all the ls7 failures, see his old posts. He had about 35 dropped valve cases documented in his spreadsheet. That was years ago.

Another statistical analysis I did was on the mileage distribution...I concluded that the z06 population was not accumulating mileage very fast, in fact we wouldn't see most failures for years.

Guess what? Gm concluded the same thing. They'll be out of warranty before they pop, so as long as nobody spins into a semi on the interstate, we don't have to do a recall. Lol there have been two fires posted due to dropped valves with pictures.

So believe it or not, 6.5 failures per thousand may have been a true statement at one point in time, say, when the vast majority of all the ls7 had less than 20k miles. But what will the failure rate be when they've all had a 100k miles?

Hopefully it will be a lot lower because of people being proactive on this forum.


https://www.corvetteforum.com/forums...-registry.html

https://www.corvetteforum.com/forums...-registry.html
Excellent post


DH
Dirty Howie is offline   Reply With Quote
Old Yesterday, 01:41 PM   #103
MH663
CF Senior Member
 
MH663's Avatar
 
Member Since: Jul 2014
Location: Dayton OH
Posts: 756
Thanked 71 Times in 66 Posts
Default

Quote:
Originally Posted by rockinSeat View Post
I did a statistical analysis once (see my prior posts). It was something like, with 30,000 z06s as a population, to get within +/- 10% accuracy we need a sample size of like 4 or 5 hundred cars. So if you look at the out of spec registry thread below, and it's sister thread the in-spec registry, there were 200 out of spec and about 25 in spec.

So my statistics are a bit rusty, but I think I could say with about 100 percent confidence that at least half of them are f'd up.

also, there was a helpful member here who used to keep a record of all the ls7 failures, see his old posts. He had about 35 dropped valve cases documented in his spreadsheet. That was years ago.

Another statistical analysis I did was on the mileage distribution...I concluded that the z06 population was not accumulating mileage very fast, in fact we wouldn't see most failures for years.

Guess what? Gm concluded the same thing. They'll be out of warranty before they pop, so as long as nobody spins into a semi on the interstate, we don't have to do a recall. Lol there have been two fires posted due to dropped valves with pictures.

So believe it or not, 6.5 failures per thousand may have been a true statement at one point in time, say, when the vast majority of all the ls7 had less than 20k miles. But what will the failure rate be when they've all had a 100k miles?

Hopefully it will be a lot lower because of people being proactive on this forum.


https://www.corvetteforum.com/forums...-registry.html

https://www.corvetteforum.com/forums...-registry.html
Yes, nicely stated.
MH663 is offline   Reply With Quote
Old Yesterday, 06:02 PM   #104
MTPZ06
CF Senior Member
Support Corvetteforum!
 
MTPZ06's Avatar
 
Member Since: Dec 2008
Location: Honolulu HI
Posts: 8,537
Thanked 484 Times in 427 Posts
Default

Hard to believe in 2017 that people still drink the 1% Kool-Aid...
MTPZ06 is offline   Reply With Quote
Old Today, 11:52 AM   #105
Michael_D
CF Senior Member
 
Michael_D's Avatar
 
Member Since: Aug 2010
Posts: 3,925
Thanked 188 Times in 152 Posts
Default

Quote:
Originally Posted by MTPZ06 View Post
Hard to believe in 2017 that people still drink the 1% Kool-Aid...
Stupidity does not have an expiration date.
Michael_D is offline   Reply With Quote
Go Back   CorvetteForum - Chevrolet Corvette Forum Discussion >
Reload this Page
  • Newbie with LS7 Questions
  •  
     
    Reply

    Related Topics
    Thread Thread Starter Forum Replies Last Post
    New member. Premier Edition C7 Blu-rayZ51 Intros 9 05-31-2017 09:07 PM
    [Z06] C6zo6 Bandairas C6 Corvette ZR1 & Z06 12 02-21-2017 02:44 PM
    Valve guide problems - LS3 vs LS7 pmt67usa C6 Tech/Performance 3 12-22-2016 12:02 PM
    Good deal on this 2007 Z06? corvettes4ever C6 Corvette General Discussion 14 05-27-2016 10:26 AM
    LS9 cam w/boost + ls3 / ls6 valve springs? mourat C6 Forced Induction/Nitrous 9 10-20-2011 04:21 AM


    Thread Tools Search this Thread
    Search this Thread:

    Click for Advanced Search

    Posting Rules
    You may not post new threads
    You may not post replies
    You may not post attachments
    You may not edit your posts

    BB code is On
    Smilies are On
    [IMG] code is On
    HTML code is Off
    Trackbacks are Off
    Pingbacks are Off
    Refbacks are Off

    Forum Jump


    All times are GMT -4. The time now is 06:28 PM.


     
    • Ask a Question
      Get answers from community experts
    Question Title:
    Description:
    Your question will be posted in: