Attention Valve Spring Failures/Concerns
Race Director
Joined: Oct 2008
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From: NJ
Instructor
Joined: Oct 2014
Posts: 100
Likes: 9
From: Woodlands Texas
Valve springs keep popping up as a recurring GM V8 problem. A friend’s 2017 Denali had one fail and dealer tech told him they were handling replacements on multiple trucks/SUV every day. I don’t understand why GM tolerates suppliers who produce faulty products. They are ruining their reputation.
Banned Scam/Spammer
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From: Bonita Springs FL
Drifting
Joined: Feb 2017
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Valve springs keep popping up as a recurring GM V8 problem. A friend’s 2017 Denali had one fail and dealer tech told him they were handling replacements on multiple trucks/SUV every day. I don’t understand why GM tolerates suppliers who produce faulty products. They are ruining their reputation.
Drifting
Joined: Feb 2017
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Safety Car
Joined: Oct 2015
Posts: 4,128
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From: St Louis Area IL
A guy in our club was building a C2 resto mod, and showed me the LS3 truck motor he was installing. He said it was far cheaper and just as good as the Corvette version. I still remain skeptical of that. I doubt you are going to exceed triple digit speeds or do 3 second launches in a C2, but still.
Instructor
Joined: Nov 2004
Posts: 232
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From: New Port Richey, Fl
maybe a minor point, but Corvettes LT2 engines would require ALL Spring be replace (per the Advisory) which my read says if a spring goes, then ALL of them need to be replace. ?
i believe the point on the 5000 affected made by NextOne is tied to that many cars being built over the time frame in question.
Last edited by Dan Delena; Sep 24, 2020 at 09:47 AM.
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Instructor
Joined: Oct 2014
Posts: 100
Likes: 9
From: Woodlands Texas
Frustrating because GM and reputable suppliers know how to build springs that work. Look at the millions of Chevy V8 engines produced and the thousands of miles covered by each and valve spring failures have always been rare until recent history.
E-Ray, 3LZ, ZER, LIFT
Joined: Sep 2007
Posts: 35,018
Likes: 12,400
From: NE South Carolina
^^^
Yep GM could use high end spring suppliers like the Manley Performance info I posted in #57 above.
But I condensed their comments; their 1st intro paragraph said:
"With seemingly square-lobe camshafts being produced today that provide tappet acceleration rates previously unheard of and valvetrain motion so aggressive it can turn the stoutest of pushrods into a spaghetti noodle, the need for superior valve spring technology combined with unsurpassed durability is greater than ever before."
Yep the small block I had in my '56 Chevy with the same bore spacing (albeit smaller diameter pistons and less stoke) as the LT2 never saw anything like today's valve spring strength performance requirements. Heck NHRA ProStock cars are probably replacing their 10,500 max rpm valve springs every race (they were turning ~13,000 before NHRA put on a limit.) Yep producing their ~1500 NA hp power requires huge valves on 500 cid engine and not doubt close to "Square" cam lobs as Manley said "tongue-in-cheek!" 495 NA from a small block also requires lots of lift, fast!
Yep GM could use high end spring suppliers like the Manley Performance info I posted in #57 above.
But I condensed their comments; their 1st intro paragraph said:
"With seemingly square-lobe camshafts being produced today that provide tappet acceleration rates previously unheard of and valvetrain motion so aggressive it can turn the stoutest of pushrods into a spaghetti noodle, the need for superior valve spring technology combined with unsurpassed durability is greater than ever before."
Yep the small block I had in my '56 Chevy with the same bore spacing (albeit smaller diameter pistons and less stoke) as the LT2 never saw anything like today's valve spring strength performance requirements. Heck NHRA ProStock cars are probably replacing their 10,500 max rpm valve springs every race (they were turning ~13,000 before NHRA put on a limit.) Yep producing their ~1500 NA hp power requires huge valves on 500 cid engine and not doubt close to "Square" cam lobs as Manley said "tongue-in-cheek!" 495 NA from a small block also requires lots of lift, fast!
Last edited by JerryU; Sep 24, 2020 at 10:08 AM.
Race Director
Joined: Oct 2008
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From: NJ
Please. The springs are not even the real issue. Mfrs do not build them to last. Look how much plastic and rubber is on the inside? It's amazing to me any of these engines last as long as they do. It doesn't benefit chevy or Ford or any mfr to make the engines out of materials that will last a lifetime even if they charged 20k more for the car.
Melting Slicks
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From: Rochester New York
https://www.corvetteforum.com/forums...already-9.html
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From: Bonita Springs FL
Once again, can't wait to hear our conspiracy theorists take on reality. Fire at will!
Team Owner
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From: Raleigh
I remember my C5 z06 and always being asked if it was an oil burner. On to the C6 z06 and always being asked if the heads were done yet or if it had dropped a valve. And now this.
Believe me you guys are going to love it !
Believe me you guys are going to love it !
Le Mans Master
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From: Metro Detroit Michigan
Banned Scam/Spammer
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From: Bonita Springs FL
Any rational person who follows the automotive world is able to understand this as that scenario has been seen many times before, bad gears from China, killer air bags from Japan, and on. Don't waste your time with this clown, he has a death grip on his C8 hate. Really weird indeed.
Race Director
Joined: Oct 2008
Posts: 16,671
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From: NJ
Valve springs keep popping up as a recurring GM V8 problem. A friend’s 2017 Denali had one fail and dealer tech told him they were handling replacements on multiple trucks/SUV every day. I don’t understand why GM tolerates suppliers who produce faulty products. They are ruining their reputation.
Le Mans Master
Joined: Apr 2020
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and I'l possibly be the next to raise the limit?I remember when companies like Boeing did everything in house to control quality vs make the most Dinero. The trade off is $$$ vs no (less) problems.
Last edited by C8J; Sep 24, 2020 at 04:18 PM.
E-Ray, 3LZ, ZER, LIFT
Joined: Sep 2007
Posts: 35,018
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From: NE South Carolina
First surprise was there was no drama! No wheel spin (I could detect.) Faster than my street rod that has more power/torque, 53% of it's weight on the rear 420 section width Mickey Thompson tires! It has lots of drama on the start of a banzai run! Have to check my PDR! Shifted at 6000 rpm and all valve springs still fine!
Last edited by JerryU; Sep 24, 2020 at 04:49 PM.
Drifting
Joined: Feb 2017
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OK, so the auto press who you know for a fact lies about everything then lied once again about the 992S? 0-60 is not 2.9? Is it really 3.9? 4.9? Why don't you tell the rest of us here the whole truth and nothing but the truth. What are the real #s since you seem to be so sure about the absolute lack of integrity on the part of the auto press.
Once again, can't wait to hear our conspiracy theorists take on reality. Fire at will!
Once again, can't wait to hear our conspiracy theorists take on reality. Fire at will!
