My LS1 Valve spring testing results....
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Joined: Aug 1999
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From: Lackey, my own dragstrip VA.
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My LS1 Valve spring testing results....
As some of you may remember I broke an Exhaust valve spring on my stroker back in October of last year. I replaced both intake and exhaust springs on the #6 cylinder only as I did find a factory defect causing a stress riser and an untimely spring break( Of course hitting the rev limiter doesn’t help either 
)
I finally had a chance to test the old Pioneer intake spring that did not break and a few of the new Patriot Performance Gold springs. (Thanks to Steve & Rob at Abacus) The results would tell me if after 7K hard miles I need to replace all 16 springs or just the 2.
Used 7K+ mile Pioneers from Cartek’s 4X heads
Installed Height 1.800" = 120lbs
Valve Spring Open Pressure 1.200" = 370-375 lbs
Brand spanking new unused PP Golds (Note, these will lose ~10% strength after break in)
Installed Height 1.800" = 145 lbs average
Valve Spring Open Pressure 1.200" = 375 lbs average
Based on my results and continued good performance I WILL NOT CHANGE ANYTHING ELSE AT THIS POINT
And for some good FAQ on the above here is a good place to go.
http://www.cranecams.com/?show=valveSpringsFAQ
) I finally had a chance to test the old Pioneer intake spring that did not break and a few of the new Patriot Performance Gold springs. (Thanks to Steve & Rob at Abacus) The results would tell me if after 7K hard miles I need to replace all 16 springs or just the 2.
Used 7K+ mile Pioneers from Cartek’s 4X heads
Installed Height 1.800" = 120lbs
Valve Spring Open Pressure 1.200" = 370-375 lbs
Brand spanking new unused PP Golds (Note, these will lose ~10% strength after break in)
Installed Height 1.800" = 145 lbs average
Valve Spring Open Pressure 1.200" = 375 lbs average
Based on my results and continued good performance I WILL NOT CHANGE ANYTHING ELSE AT THIS POINT
And for some good FAQ on the above here is a good place to go.
http://www.cranecams.com/?show=valveSpringsFAQ
Melting Slicks
Joined: Apr 2001
Posts: 2,877
Likes: 7
It's good to see your orginals are holding up well. I have about 2500 miles on my comp 921's. When I get the time I am going to check them all to make sure they are holding up as well.
I would rather not go through a dropped valve due to a faulty spring
I would rather not go through a dropped valve due to a faulty spring
