[Z06] Broken valve spring replacements.
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Broken valve spring replacements.
Hey everyone. I am working on my Daily Driver C5z. Anyways Tuesday Am the car fired up and developed a nasty misfire. Chased down the basics but everything looked good. Well today I had some time and I yanked the valve covers to find a broken valve spring on intake #8. Car is a 2003 and looks to already have had a valve spring change as these are not yellow or blue. I knew this when I got the car. So next up I am going to inspect the piston and valve to make sure nothing touched. If so I plan to swap the springs and hopefully we are good to go. The car is a daily with a stock cam so if I am correct these springs are just the later stock replacements. Part number 19420455 or is it 12499224
For those you want to see the carnage. Still clean for 115k miles.
For those you want to see the carnage. Still clean for 115k miles.
Last edited by 96Formula6spd; Jan 6, 2024 at 05:40 PM.
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Hopefully there was not any collateral damage from the valve spring.
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PAC springs for the win!! Just don't buy them from Bozo (Amazon) or ebay. OP was lucky from the looks of things. 99% certain he is good to go. I have 52,000 miles on my modded LS7, cam has over .600" lift. PAC dual springs also have 52,000 miles. Set 'em, and forget 'em......
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I mean stuff happens. I know while driving it home before it saw redline. Most of the time it's bumming around below 2k rpm. But I'm not afraid to get on it. Hopefully the valve did not touch. If so I'm good to go with 16 new springs. Cause of one mystery meat valve spring failed who knows about the rest.
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Cam is stock. Sounds the same as any other stock c5z. Mine has a sway bar and some koni shocks. I added a corsa extreme a few years ago. But I bought it from he last owner as an A Street Autox car. Shoot it won first and second at solo nationals in 2018 in A Street.
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My Z was built in April of '03 and never had the springs changed before I got it (I know the previous owners). When I went to change mine to PAC 1218 the springs that were in there were bare metal. I expected yellow springs as well, but didnt see them.
I track my car and have a stock cam. No need for expensive or dual springs. PAC 1218 have been great for the last 3 years of abuse.
I track my car and have a stock cam. No need for expensive or dual springs. PAC 1218 have been great for the last 3 years of abuse.
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Well went ahead and ordered some stock replacement "blue" springs. They are no longer blue. They will be here Wednesday. My budget has been shot over the last few months of everything breaking. I just ordered two sets of tires. One for my truck and one for the miata. So blue springs are going in for now. I have been toying with selling the car so who knows what will happen after I fixed it.
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Blues are good too, but should probably be replaced a little more often. I am doing springs again in my car after 3 years of track use. I know some people do springs every year just as insurance before breaking one. The material is a better steel on the PAC springs so I felt more comfortable stretching it longer.
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Well went ahead and ordered some stock replacement "blue" springs. They are no longer blue. They will be here Wednesday. My budget has been shot over the last few months of everything breaking. I just ordered two sets of tires. One for my truck and one for the miata. So blue springs are going in for now. I have been toying with selling the car so who knows what will happen after I fixed it.