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Hey crew

Picked up an 03 z06 with 32k. I've read about the unfortunate occurence of valve spring issues. For my ease, would you guys recommend BTR dual springs on stock cam. I don't plan on doing more than your basic bolt ons. Also, would I need pushrods as well?
 

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I read an article in a Vette magazine a couple of months ago regarding this issue. I have an '02 Z that I track 4-5 times a year. I have had no problems but went ahead and replaced them with stock '04 Z springs. The stock springs were very reasonable less than $100. for the set. Worth the piece of mind!
 

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I am working from memory here, and this was over a decade ago....

I recall GM admitting that they had a bad set of springs from a supplier in 2Q 2002 which resulted in many spring/engine failures. I was during that build period and was one of them.

While GM ultimately admitted there was a problem, they cited a "statistical insignificance" to warrant a recall.
 

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I just purchased a 2003 z06 with 53K miles. its build date is between Sept 6 and Sept 16th according to the build table (was there a shutdown in between those dates?). Anyway my question is should I change the valve Springs if the bad springs were a Q2 2002 problem? I don't plan to race the car other then the occasional street drag/race. THANKS
 

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I was driving my 2002 Z06 at Autobahn CC in an HPDE when the check engine light came on. The OBD code was #2 cylinder misfire. Several of us (including a couple of Corvette engineers who just happened to be there) listened for noise, and checked for oil contamination. We also pulled the spark plug to look in the cylinder as much as we could. Based on that, everyone agreed I could drive it home (about 4 hours drive with me keeping engine and car speed slow). The mileage when this happened was about 49,500.

When I got home, I tried everything I could to diagnose it, electrical and fuel, swapping components with #4. The OBD code always showed the problem on #2. I ran a regular compression test, nothing wrong. So I took it to a Chevy dealer who had a dedicated Corvette mechanic. He skipped over everything that I had already done, and went right to doing a "running compression test." He concluded it was a valve problem, and pulled the cover and found what you can see in the photo. After removing the valve train, he examined the cylinder, piston, and valve guide, and concluded there was no other damage, not even a sign of wear on the valve guide. Apparently the break occurred so close to the end of the coil that the broken piece was contained, and the rest of the spring prevented valve to piston damage. But the weakened spring was not enough to keep the valve from floating at higher engine speeds, causing the misfire. Unless this is characteristic of all of the defective valve spring failures, I have to conclude that I was EXTREMELY lucky.

I had the mechanic put in a new full set of springs. The replacement springs were painted blue. I like to think that they were painted blue to designate that they were "good" springs, but maybe they paint all parts system springs blue.

I've put 14,400 miles on it since, and that included five track days. I've had no problems. So there is life after valve failure.
 

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