Cam Swap = Valvetrain Noise

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Mar 1, 2006 | 12:24 AM

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Cam Swap = Valvetrain Noise

I just changed the cam, valve springs, oil pump, and timing chain in my 5.3 SC truck. I have a loud ticking noise that will come and go. It doesnt matter what the rpm and temperature of the engine is. Truck has 44k on the odometer.

I have about 60 psi of oil pressure at idle and about 75 at 2000+ rpm.

I double checked the rockers and they are torqued to 22ft lbs of torque.

What could it be? Bad lifters?

PLEASE HELP!!!

Mar 1, 2006 | 03:19 AM

co.6z28

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From: huntingtown ,MD

its prob the heavier valve springs

Mar 1, 2006 | 03:25 AM

cantdrv65

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From: TEXASS

Quote:

Originally Posted by j's01silverado

The combination of beefier valvesprings and less preload on the lifers will result in a little more valvetrain noise. Shouldnt be too bad though, if so you may have a problem.

Mar 1, 2006 | 05:28 AM

vettenuts

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From: Little Rhody

If it comes and goes, I would go in and double check the rockers, pushrods, etc. This indicates a problem rather than just general valve train noise associated with a cam swap. Do you have more details on your setup? (Cam, pushrod length, etc.)

Are your supercharged? I remember someone on the truck forum having a noise issue setting off the KR and it was the supercharger that turned out to be the issue. If I remember correctly, he had installed a Vinci cam and Roger Vinci found the problem as they had run across it before. You might want to search on the truck forum if you haven't already.

Mar 1, 2006 | 07:13 AM

orangeapeel

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From: Justin, TX

Sounds like it might be a slightly bent pushrod. Well, you will definitely have some valve train slack as well like was said before with heavier duty valve springs.

Mar 1, 2006 | 09:22 AM

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The truck has a Magnacharger on it. I did double check the rocker bolts and torqued them down to 22 ft lbs of torque.

The cam is rather mild, Lingenfelter GT2-3 207-220 .571/.577 on a 118.5 lsa. I am using the yellow ls6 springs. Pushrod length is standard 7.4" I was told by Lingenfelter that the stock pushrods would be fine.

What confuses me is the noise will come and go. I know that some valve train noise is normal, I just dont understand why it would get louder at times at times and then go away.

Some have made the suggestion of a bad/collapsed lifter, I reallydont know though. This noise is really bothering me.

Mar 1, 2006 | 09:41 AM

ArKay99

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That cam is not that big, but the base circle is defintely going to be smaller than stock. Since you didn't change heads or mill and haven't changed your gasket thickness, I would say your pushrods are too short. The best way to determine the proper PR length is with a PR length checker. It takes about 10mins. Then order new pushrods.