Let’s Tune This Engine

Hm. Now this is interesting:

“The XE or "extreme energy" cams are fast ramp cams that take maximum advantage of the lobe ramps that are possible with a hydraulic roller cam. This offers a power advantage over more milder lobe ramps. The XE cams will tend to make more noise than the milder ramp cams - this shouldn't be surprising to anybody. Because of the cams fast ramps, the cams will tend to sound like a solid lifter cam. If you look at the duration at .050 and then look at duration at .200 on Comp Xtreme energy cams and compare it to others, you realize that the comps have extremly fast lobes.“

This seems to me the issue.

The lifter noise is a result of the cam’s extreme ramps and not a failure of the lifters.

The vacuum needle vibration may well be related to this.

If this is the case... as long as I know it’s normal, I can live with it. Under the hood is unsettling. But I don’t drive around with my head under the hood.

I think I’ll reset the valve lash one last time to the recommended 1/2 turn and call it good. In a year or three, I may swap out to a quieter cam.

source:
https://www.fordmuscleforums.com/threads/xe-cams-some-valvetrain-noise-see-this.475049/
 
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DorianL said:
If you look at the duration at .050 and then look at duration at .200 on Comp Xtreme energy cams and compare it to others, you realize that the comps have extremly fast lobes.“
Click to expand...
But you don't have an XE series cam, you have the XR series. Are you confused or just
explaining the noise.

Faster ramps make for better performance, but it's harder on the valve train. The Hydraulic
Intensity of your XR270HR is 52 (270 - 218 = 52), which seems about right for a street
camshaft. HI only considers the first 0.050 inches of lift.

CompCams_HR_XR270HR_495_502.jpg considers the first 0.050 inches of l
 
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Indycars said:
I think Bob was talking about the clearance between the bottom side of the rocker arm and
the valve retainer. Location "C" in the photo below.

rpo1x.JPG
Click to expand...
Yes, you are exactly right Rick! Mine had a rough corner like looking spot right there in your picture and it did clear but it was just too close for my comfort, so I used a cartridge roll and relieved it just a little. They all had the little, I guess you could call it a flaw maybe. But, I rounded it with the cartridge roll and it went from 1/32 all the way through the movement of valve/rocker and pushrod, after it was minimum of 1/16 maybe even more, maybe 3/32. I never actually measured it. My reason for mentioning this, is the bent pushrod, just that all of the valvetrain geometry needs to be checked, that was one that I encountered with my engine, it's not always mentioned. I think Grumpy was the only one I saw that mentioned the rocker to retainer clearance is sometimes a problem. So I mentioned it, so it would be something that Dorian is aware of sometimes causing clearance issues.
 
DorianL said:
Hm. Now this is interesting:

“The XE or "extreme energy" cams are fast ramp cams that take maximum advantage of the lobe ramps that are possible with a hydraulic roller cam. This offers a power advantage over more milder lobe ramps. The XE cams will tend to make more noise than the milder ramp cams - this shouldn't be surprising to anybody. Because of the cams fast ramps, the cams will tend to sound like a solid lifter cam. If you look at the duration at .050 and then look at duration at .200 on Comp Xtreme energy cams and compare it to others, you realize that the comps have extremly fast lobes.“

This seems to me the issue.

The lifter noise is a result of the cam’s extreme ramps and not a failure of the lifters.

The vacuum needle vibration may well be related to this.

If this is the case... as long as I know it’s normal, I can live with it. Under the hood is unsettling. But I don’t drive around with my head under the hood.

I think I’ll reset the valve lash one last time to the recommended 1/2 turn and call it good. In a year or three, I may swap out to a quieter cam.

source:
https://www.fordmuscleforums.com/threads/xe-cams-some-valvetrain-noise-see-this.475049/
Click to expand...
I only go 1/4 turn past zero lash myself, it sometimes causes a lifter click, but I will just readjust it to quieten it down.
 
Indycars said:
But you don't have an XE series cam, you have the XR series. Are you confused or just
explaining the noise.

Faster ramps make for better performance, but it's harder on the valve train. The Hydraulic
Intensity of your XR270HR is 52 (270 - 218 = 52), which seems about right for a street
camshaft. HI only considers the first 0.050 inches of lift.

View attachment 15014 considers the first 0.050 inches of l
Click to expand...
Yes Rick, that is actually a Xtreme Energy cam, CS XR270HR-10 is the grind number, go to Compcams website and its in the XE series. The hydraulic flat tappet cams have the XE in their grind number. The roller version have XR to show they are a roller cam!
 
I guess the marketing department got priority consideration again to help the bottom line.
 
High energy are like a step above stock replacement, I went through all their series when I was choosing my cam!
 
It all seems to fit. The vague noise. The vacuum needle.

There is a lot of material out there on these Xtreme Energy Retrofit hydraulic roller cams and how noisy they are. They describe exactly what I’m going through to a T.

The valve train noise isn’t excessive. It’s just enough to make me raise an eyebrow. It’s not what I’m used to. It’s how I would imagine mechanical lifters would sound, or better yet, Rhoads lifters.

Were this a lifter related issue, I could understand if 1, 2, or 3 liters even had failed and were making noise. Here it seems to be all of them.

All sources say it’s the aggressive ramps. Even Comp Cams website boasts about them as “taking maximum advantage of roller technology”.

Would I take this cam again ? Not likely. Will I get used to it ? Maybe. Can I live with it for a little while ? Yes.

My plan is to bring preload back down, replace the gaskets on my valve covers :mad: and learn to live with the vague valve train chatter. Most of the time you can’t hear it from the driver’s seat.
 
Yeah Dorian, that was my reason for picking mine in the Magnum Series of cams. Few of my buddies in the Nova club here, say their XR rollers are a little noisey.
 
one reason I prefer CRANE and CROWER and ERSON CAMS,
is that most are designed for long term DURABILITY and less valve train stress,
yeah you might give up 5-7 peak hp, compared to a similar COMP version,
but you also tend to get 60-70K plus miles or more without a valve train wear issue
thats in my experience double to triple the mileage between,
having to do a minor maintenance rebuild on the valve train, components
 
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Well, I would have happily given up a few HP for a few decibels less.

At this point it’s time to drive it for the season... you know, enjoy ?

My feeling is I will replace this next year or the year after.
 
Compcams Magnum rollers are pretty good, if you contact them on the phone they can make them on a billeted core. Mine originally was on a standard core, I called and it cost 50 bux plus shipping. I think your engine would do pretty good with the cam I have. Its the Magnum 280 roller, 224/224 dur @ 50, 525 lift(with 1.55 = 542), LSA 110, LCA 106, valve overlap is 60.
 
Valve train noise aside, what I would be investigating is the vacuum gauge needle bouncing. You said it is perfectly rhythmic, correct?
What happens on the vacuum gauge if you pull the plug wires one at a time at idle?
 
I re-did the preload to all my valves. It’s not as noisy as I remember. Maybe I’m being paranoid with a new cam.

Loves302Chevy said:
Valve train noise aside, what I would be investigating is the vacuum gauge needle bouncing. You said it is perfectly rhythmic, correct?
What happens on the vacuum gauge if you pull the plug wires one at a time at idle?
Click to expand...

This is to find if it’s dropping ignition to a cylinder, yes ? Wouldn’t temp gun reveal that as well ?

Where are my rubber gloves. I always get zapped !
 
42545.jpg

yes a decent infrared temp gun is a helpful diagnostic tool
keep in mind , even if everything running well,
the front two cylinders tend to run a small amount cooler (20 degrees) simply because the increased cooler air flow over the header tubes
the actual exhaust gas and header temp will vary with the combo specs , your looking for consistency not a specific temperature at the exhaust ports
http://www.testequipmentdepot.com/extech/thermometers-and-humidity-meters/infrared-thermometers/high-temperature-infrared-thermometer-58to1832f-50to1-laser-pointer-42545.htm?utm_source=bing&utm_medium=cpc&utm_campaign=NEXT - Bing Shopping - Extech&utm_term=1100200223789&utm_content=All Extech Products


http://garage.grumpysperformance.com/index.php?threads/odd-exhaust-temps-and-failed-smog-test.15817/
 
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DorianL said:
I re-did the preload to all my valves. It’s not as noisy as I remember. Maybe I’m being paranoid with a new cam.



This is to find if it’s dropping ignition to a cylinder, yes ? Wouldn’t temp gun reveal that as well ?

Where are my rubber gloves. I always get zapped !
Click to expand...

ZZZZAP !!!! Well the rubber gloves failed. My that ignition box is powerful.
 
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