Weird Suspected Valve Train Noise
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TECH Regular
Joined: Dec 2012
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From: San Diego
Weird Suspected Valve Train Noise Ok so i noticed a ticking noise shortly after i started driving my Camaro with its new iron 408. Then probably a day latter i noticed a squeeling almost like a belt. I dont think its a belt because all my belts are new. So what else could it be?
Teching In
Joined: Nov 2011
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I had the same exact issue in my 06 GTO. I am replacing my cam and lifters this weekend. I suspect you have a lifter failure. I had the tapping and strange squealing belt sound as well. There was a lifter tap, but also a rattle sound or clacking that could be heard if I revved through the 1,500-2,5000 rpm range.
I pulled my intake and lifter valley cover to peek at the few lobes that can bee seen this way. I have some interesting wear patterns there. It looks like one of my lobes was wearing some, although the roller for the lifter doesn't appear to be frozen or anything. A buddy suggested that my cam may have not been property heat treated. I expect to find a lifter with a roller that has failed once I pull the heads and lifters out.
I was running some lunati linkbar "street" lifters, but am going back to LS7 lifters/trays with my new cam. My old cam was an comp XER281 (232/234 .595/.598 113) and the new cam is an LSR 231/239 .617/.624 113. Replacing the valvesprings too, which are lunati dual golds.
I put about 30k miles on this cam and valvesprings, and maybe 25k on the lunati lifters. I will replace my valvesprings every 15k or so now. I may have mine tested just to see if they held up, or perhaps they got weak and contributed to my issues.
I pulled my intake and lifter valley cover to peek at the few lobes that can bee seen this way. I have some interesting wear patterns there. It looks like one of my lobes was wearing some, although the roller for the lifter doesn't appear to be frozen or anything. A buddy suggested that my cam may have not been property heat treated. I expect to find a lifter with a roller that has failed once I pull the heads and lifters out.
I was running some lunati linkbar "street" lifters, but am going back to LS7 lifters/trays with my new cam. My old cam was an comp XER281 (232/234 .595/.598 113) and the new cam is an LSR 231/239 .617/.624 113. Replacing the valvesprings too, which are lunati dual golds.
I put about 30k miles on this cam and valvesprings, and maybe 25k on the lunati lifters. I will replace my valvesprings every 15k or so now. I may have mine tested just to see if they held up, or perhaps they got weak and contributed to my issues.
Teching In
Joined: Nov 2011
Posts: 18
Likes: 1
I am done with my swap. I had some severe pitting on one of my lunati lifters, and few others had mild pitting. All the rollers were functional.
New cam is in, car runs great.
Did you pull the heads and inspect? What was the outcome of this?
New cam is in, car runs great.
Did you pull the heads and inspect? What was the outcome of this?
