Roller rockers
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
The thing is if the preload exists at all times as it should in a hydraulic lifter, then the axles on the pivot and the tips never get "unloaded" in order to get the slack required to make noise.
I would guess also that something is amiss in the set up somehow. I can hear my lifters but it's not what I would qualify as noisy. Quieter than the roller tipped lifters that had pivot *****. Quieter than the stock lifters too.
How aggressive the lobe is on the cam I would guess would have some influence, but I would think only at high RPM if the lifter lost contact with the valve stem tip due to inadequate spring pressure, or at least was unloading at the time it was reversing direction and significantly reducing the pressure exerted on the valve stem tip and pivot point.
Maybe the noise you're hearing is the valves slamming shut due to an aggressive closing ramp combined with high spring pressure that is necessary to control and aggressive lobe profile.
I would guess also that something is amiss in the set up somehow. I can hear my lifters but it's not what I would qualify as noisy. Quieter than the roller tipped lifters that had pivot *****. Quieter than the stock lifters too.
How aggressive the lobe is on the cam I would guess would have some influence, but I would think only at high RPM if the lifter lost contact with the valve stem tip due to inadequate spring pressure, or at least was unloading at the time it was reversing direction and significantly reducing the pressure exerted on the valve stem tip and pivot point.
Maybe the noise you're hearing is the valves slamming shut due to an aggressive closing ramp combined with high spring pressure that is necessary to control and aggressive lobe profile.
I just encountered valve train noises on a friends engine. That went away with a valve cover swap . LMFAO .. He was furious everyone else was selling horror stories on his new motor. Now he can change the oil and filter, let it run for 20 minutes preferably with 1qt of trans fluid to flush the oil passages out. And then put his second new filter on and new oil..
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
No real benefit on the street......the Comp Magnum roller tip deal is a sturdy piece....and as stated, the ratio will be spot on compared to mass produced stamped rockers which can be as much as .1 off......
I do believe there is some friction benefit....that is why the LS engines have them.....maybe a little less heat.
But I will use them a lot on a performance build over .500 lift and always with hydraulic roller.....as spring pressures approach 400+ psi over the nose.....they make sense to me.
As far as noise though......they should not be audible enough to be concerned about it......it is quite possible that some hyd. lifters are not happy with 400 psi open.....once the rocker hits the polar moment of inertia and changes direction after being plunged by too much pressure, you would here the rocker catching up.....
Jebby
I do believe there is some friction benefit....that is why the LS engines have them.....maybe a little less heat.
But I will use them a lot on a performance build over .500 lift and always with hydraulic roller.....as spring pressures approach 400+ psi over the nose.....they make sense to me.
As far as noise though......they should not be audible enough to be concerned about it......it is quite possible that some hyd. lifters are not happy with 400 psi open.....once the rocker hits the polar moment of inertia and changes direction after being plunged by too much pressure, you would here the rocker catching up.....
Jebby
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I know first hand that a modern LS3 factory h-roller will make a racket if you install too thin of oil. Friend had an oil change at some place like Jiffy Lube and on the window sticker reminder on mileage for next change said 5W-20 and this was 100 degree summer season. Right on the cap said 10w-30 and over a certain temperature like 90 in the book said 10W-40.
I drained out the oil and filled it with 10w-40 and It was back to quiet
I drained out the oil and filled it with 10w-40 and It was back to quiet
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 492
From: Salmon Arm, BC
I am more than happy to hear realistic, and factual "technical" information about the noise and how to fix it.
I have a Mike Jones cam that I can provide numbers for, but which is a rather intense cam......but again, there is a very common statement on multiple threads that roller rockers have a "sewing machine" sound to them. Which is not the sound of a factory rocker and is not quiet.
I have a Mike Jones cam that I can provide numbers for, but which is a rather intense cam......but again, there is a very common statement on multiple threads that roller rockers have a "sewing machine" sound to them. Which is not the sound of a factory rocker and is not quiet.
I had a very noisy hydraulic roller valvetrain a few years ago....sounded like a damn sewing machine
Like many others I tried every adjustment method I could with no relief from the noise. I also tried changing the oil viscosity as well with no luck at all. I had the Comp XR276HR in my engine with Comp 1.6 ultra pro magnum roller rockers. I can't remember exactly what the lift was but in the neighborhood of .540" liftAfter much reading on the web about this I figured out it was my camshaft....lobe profiles that were just too aggressive for quiet operation. I changed out the cam to a Crower Cam with slightly more duration and similar lift, and with that one change my valvetrain is now quiet to 6300 RPM.
You say your cam is "rather intense" you should ask Mike Jones what lobe profiles he used to see if it was the Comp XE series of lobes or something with similar aggressive profiles.... he may be able to tell you whether it is a noisy lobe or not.
---------------------------------------------------------------------
Back to the topic at hand....To the opening poster, Jebby touched on it some, but if your lift is over .500" the stamped rockers tend to put allot of side load on the valve stems, and will wear the guides out quickly. The real benefit of a roller is the lack of side load they impose on the guides.....plus they look cool
Racer
Joined: Jan 2020
Posts: 470
Likes: 147
From: Va.Beach Va.
When lifters may not pump up due to excessive spring pressure, a test using a 0wt oil can allow pump them up to prove out a possible solution
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
Gkull says that oil TOO thin is the problem with noisy valve train......and GordonR says the solution is thin oil.......is it no wonder that a person cannot find a consensus on something as simple as a V8 engine. And posters on here try to tell me to just "do what they say"?????
Last edited by Shovels and Vettes; Dec 29, 2021 at 08:20 PM.
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Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 492
From: Salmon Arm, BC
Le Mans Master
Joined: May 2008
Posts: 9,063
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2022 C3 of the Year Finalist - Modified
Mike Jones
[QUOTE=sstocker31;1604515157]OK I'll try....
I had a very noisy hydraulic roller valvetrain a few years ago....sounded like a damn sewing machine Like many others I tried every adjustment method I could with no relief from the noise. I also tried changing the oil viscosity as well with no luck at all. I had the Comp XR276HR in my engine with Comp 1.6 ultra pro magnum roller rockers. I can't remember exactly what the lift was but in the neighborhood of .540" lift
After much reading on the web about this I figured out it was my camshaft....lobe profiles that were just too aggressive for quiet operation. I changed out the cam to a Crower Cam with slightly more duration and similar lift, and with that one change my valvetrain is now quiet to 6300 RPM.
You say your cam is "rather intense" you should ask Mike Jones what lobe profiles he used to see if it was the Comp XE series of lobes or something with similar aggressive profiles.... he may be able to tell you whether it is a noisy lobe or not./QUOTE]
I sent email to Mike Jones.....he usually responds.
I had a very noisy hydraulic roller valvetrain a few years ago....sounded like a damn sewing machine
Like many others I tried every adjustment method I could with no relief from the noise. I also tried changing the oil viscosity as well with no luck at all. I had the Comp XR276HR in my engine with Comp 1.6 ultra pro magnum roller rockers. I can't remember exactly what the lift was but in the neighborhood of .540" liftAfter much reading on the web about this I figured out it was my camshaft....lobe profiles that were just too aggressive for quiet operation. I changed out the cam to a Crower Cam with slightly more duration and similar lift, and with that one change my valvetrain is now quiet to 6300 RPM.
You say your cam is "rather intense" you should ask Mike Jones what lobe profiles he used to see if it was the Comp XE series of lobes or something with similar aggressive profiles.... he may be able to tell you whether it is a noisy lobe or not./QUOTE]
I sent email to Mike Jones.....he usually responds.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Gkull says that oil TOO thin is the problem with noisy valve train......and GordonR says the solution is thin oil.......is it no wonder that a person cannot find a consensus on something as simple as a V8 engine. And posters on here try to tell me to just "do what they say"?????
To the poster. You can make a cam bigger than yours work if you put some thought into the springs. Xtreme Energy 248/254 Hydraulic Roller Cam for Chevrolet Small Block (compcams.com) This is in a friends 434 SBC with 1.6 RR. I specked out 146# seat and 400 ish at max lift. high vol pump Dart block max oil pressure about 75 hot. It's a dyno 650 hp with AFR 245 heads
Pumping Up: Is Hydraulic Lifter Pump-Up A Real Problem Today? (enginelabs.com)
Le Mans Master
Joined: May 2007
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From: North tonawanda NY
Racer
Joined: Jan 2020
Posts: 470
Likes: 147
From: Va.Beach Va.
gkull you are correct I am not one for writing novels. It is one of my weakness's for sure. Beehives although are the best choice for street strip applications IMO for sure as the spring harmonics are constantly changing. Spring install heights aren't as critical either.
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Funny comparison. I was the proud owner and builder of a V-8 Vega. Equipped with the same motor the Vega would win every time because of the 800 - 1000 pounds less weight. I'd rather go fast than have a pretty, but slow car!
Le Mans Master
Joined: May 2008
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2022 C3 of the Year Finalist - Modified
Mike Jones responded.
"The cam is aggressive, but not so aggressive it would cause the lifters to collapse and make noise.
It's the same cam I have in my boat. If you want to reduce the aggressiveness the valvetrain sees, you can switch to 1.5 rockers.
That would reduce the valve acceleration by over 6%.
The issue is, you are running stock lifters with high pressure springs.
You've got high performance heads, high performance valve springs, high performance camshaft, High Ratio rocker arms, and stock lifters.
This is what I told you 9 days ago, and it's still the issue: "That's too much spring pressure for stock lifters"."
"The cam is aggressive, but not so aggressive it would cause the lifters to collapse and make noise.
It's the same cam I have in my boat. If you want to reduce the aggressiveness the valvetrain sees, you can switch to 1.5 rockers.
That would reduce the valve acceleration by over 6%.
The issue is, you are running stock lifters with high pressure springs.
You've got high performance heads, high performance valve springs, high performance camshaft, High Ratio rocker arms, and stock lifters.
This is what I told you 9 days ago, and it's still the issue: "That's too much spring pressure for stock lifters"."
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
It was in my specific example of an unmodded factory motor. I'm not referring to bubba the mechanic that uses cheaper parts and doesn't understand the dynamics of valve train weight. BeeHive springs are not cheap.
If someone brought me a noisy HR the first thing I would do is the simplest. adjustments and oil. The next easy item would be to look at the springs. Very easy to change on an installed motor. lifters and last thing would be the cam.
If someone brought me a noisy HR the first thing I would do is the simplest. adjustments and oil. The next easy item would be to look at the springs. Very easy to change on an installed motor. lifters and last thing would be the cam.
Melting Slicks
Joined: Jun 2016
Posts: 2,979
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From: Woodinville WA
Whether they fit or not depends upon quite a few things.
Adam