Our Noisy Valvetrains
Thread Starter
Instructor
Joined: Jun 2008
Posts: 220
Likes: 0
From: Somers Point New Jersey
Our Noisy Valvetrains
Just did H/C swap to ported 5.3 heads and a 222/228 .567/.567 113 with patriot's extreme valve springs. I am getting a lot of valvetrain noise. The typical sewing machine sound. I was wondering how to quiet this down. I have a lot of preload on my lifters, a good 1 3/4 turns which I figure should equate to about .080 - .085 preload.
Thread Starter
Instructor
Joined: Jun 2008
Posts: 220
Likes: 0
From: Somers Point New Jersey
no, stock rockers, pusrods, and lifters. Only the spring are aftermarket. I'm trying to figure out why the hell our motors get so noisy. There MUST be something wrong somewhere.
Melting Slicks
Joined: Feb 2006
Posts: 2,163
Likes: 5
From: Houston
The rockers are non-adjustable. Tq to 22 lb-ft. If you feel like messing with it for a very long time you can shim the rockers over and over until it gets pretty damn quiet. I did that in the past with some comp-R rockers, and the valvetrain was super quiet!
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Burning Brakes
Joined: Mar 2003
Posts: 1,156
Likes: 2
From: Arlington VA
I am going to throw this out there to you. Take it for what it is worth. I am running a cam in the upper 230s with over .600 lift on 113LSA and TF 215s. When I picked the car up from ECS this past March I was pretty suprised at how much valvetrain noise it made especially right at 2200RPM. All the sources I spoke said it was normal. I put about 2500 miles on this setup. This Fall, I decided to add a bottle of ZMax micro lubricant to my normal annual oil change. All I can say is that after a couple hundred miles the noise is significantly improved. I still have some slight sewing machine noise but the noise at 2200RPM is gone. You might give this a shot. Good luck with it.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
What ramp rate is the cam you are using? I just went from a Crane cam with a slower ramp rate to an XER Comp and the noise increase was dramatic. My valve train geometry is perfect and I am using YT roller rockers.
If you didn't check your geometry and measure for pushrod length, you should really do this as part of the installation. According to my calcs, 1-3/4 turns on a M8-1.25 bolts accounting for rocker ratio is 0.137" pre-load so you are almost bottomed in the lifter. I would definitely measure.
If you didn't check your geometry and measure for pushrod length, you should really do this as part of the installation. According to my calcs, 1-3/4 turns on a M8-1.25 bolts accounting for rocker ratio is 0.137" pre-load so you are almost bottomed in the lifter. I would definitely measure.
Melting Slicks
Joined: Oct 2007
Posts: 2,464
Likes: 2
From: Cedarburg, WI
What ramp rate is the cam you are using? I just went from a Crane cam with a slower ramp rate to an XER Comp and the noise increase was dramatic. My valve train geometry is perfect and I am using YT roller rockers.
If you didn't check your geometry and measure for pushrod length, you should really do this as part of the installation. According to my calcs, 1-3/4 turns on a M8-1.25 bolts accounting for rocker ratio is 0.137" pre-load so you are almost bottomed in the lifter. I would definitely measure.
If you didn't check your geometry and measure for pushrod length, you should really do this as part of the installation. According to my calcs, 1-3/4 turns on a M8-1.25 bolts accounting for rocker ratio is 0.137" pre-load so you are almost bottomed in the lifter. I would definitely measure.
Team Owner
Joined: Mar 1999
Posts: 22,025
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From: At the beach in little Rhody
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
Le Mans Master
Joined: Dec 2003
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From: Atlanta metro Ga.
The fact that his setup now exhibits valve train noise should serve notice to all the folks out there that claim "if you have a noisy valve train it must be user error". It’s simple physics; higher ramp rates are going to accelerate and decelerate parts in a way that is impossible to completely suppress audible artifacts.
Last edited by Dan_the_C5_Man; Nov 15, 2008 at 11:54 AM.
Team Owner
Joined: Sep 2003
Posts: 43,084
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From: Raleigh / Rolesville NC
Better oiling will cut some of that noise down. I run a 3 qt accusump with a simular cam. Yes there is noise, but not too bad
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
As stated, they are not adjustable, but what I did gain was a wipe pattern that is only 0.045" wide centered on the valve stem. You won't get that with stock rockers.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Actually, I think one of the worst offenders for noise is the FAST intake. Once installed its almost like a megaphone on the lifters as there is very little noise attenuation with it.
Thread Starter
Instructor
Joined: Jun 2008
Posts: 220
Likes: 0
From: Somers Point New Jersey
What ramp rate is the cam you are using? I just went from a Crane cam with a slower ramp rate to an XER Comp and the noise increase was dramatic. My valve train geometry is perfect and I am using YT roller rockers.
If you didn't check your geometry and measure for pushrod length, you should really do this as part of the installation. According to my calcs, 1-3/4 turns on a M8-1.25 bolts accounting for rocker ratio is 0.137" pre-load so you are almost bottomed in the lifter. I would definitely measure.
If you didn't check your geometry and measure for pushrod length, you should really do this as part of the installation. According to my calcs, 1-3/4 turns on a M8-1.25 bolts accounting for rocker ratio is 0.137" pre-load so you are almost bottomed in the lifter. I would definitely measure.
Also, I am using a lunati voodoo cam. part #60511