• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

How Loud are Adjustable Rocker Arms with Hydraulic Cam?

PurpleBeeper

Well-Known Member
Local time
7:39 AM
Joined
Mar 20, 2011
Messages
5,340
Reaction score
4,087
Location
Chicago
How loud are adjustable rocker arms with a hydraulic cam? I haven't driven this car enough lately to know for sure, but mine is "sounding" like a solid lifter cam.

Background:
440 with Isky ductile iron rockers & Isky pushrods
Mopar "purple stripe" double springs
Just set the valve lash (3/4 turn in)
New Summit "cheap/stamped" valve covers for increased rocker arm clearance
Hand on valve covers doesn't "feel" like any rocker arms are hitting them
Have let engine warm up & drove it about 2 miles

What are your thoughts gentlemen?
 
Shouldn't be very noisy unless it has Rhodes
hyd.type lifters. They bleed down Abit at lower rpm.
 
Can’t hear mine at all.
 
Same here. I don't have them in the car now but I put a set of comp cams adjustable rockers in the Cuda before I sold it and no noise at all
 
I could hear mine with stamped valve covers. Aluminum M/T covers are a lot quieter and I don't hear them at all now.
 
You didn't mention your cam, but if it's any sort of modern fast ramp design, they're noisy with either rocker arm. I would almost think, you could get them to be quieter with adjustables because you could adjust your lash some to quiet them down if desired? My old XE274 gives that 'sewing machine' sound... lighter oil, heavier oil, doesn't make much difference. That said, I'm not sure if it would be as noticeable with factory exhaust manifolds.
 
Not sure if this is your problem but I will relate what happened to me.
If you have a set of lifters that bleed off more and reasonable spring pressure you can sometimes hear valve noise at idle. It must allow the preload to back off when the engine is warm and oil pressure is less. They do not really clack or tick but they are noisier than you would want them to be. Bit hard to exactly put in words.
My engine was silent when cold but valve noise at idle came in as it warmed up fully.
I did my own Ford engine and it did this. I used a Comp grind Magnum series cam and matching lifters.
The engine went really well but I was worried about the noise. I went to an engine shop and asked the owner to have a listen to the motor.
He said it is valve gear noise but I know what sort of cam you have used. He was right it was Comp. He asked if I could hear valves ticking at higher engine speeds.
I said no dead quiet above idle. He advised me not to worry it was OK.
I did own that car for a while longer and it never got worse just stayed the same.
 
Well, I'm now running a comp cams XE274 cam & lifters and the engine does have headers & cheap, stamped valve covers. The valvetrain sure seems loud though.

Some history, I just replaced some factory valve covers. The valve train was noisy, I removed valve covers & saw contact marks on the baffles, so I removed the baffles. The engine was sucking oil through the PCV hose (had air compressor drier installed in PCV hose to verify), which is why I went to these cheap ones from Summit. They seem to fit/seal fine with Felpro cork gaskets.
SUM-G3331_ml.jpg

https://www.summitracing.com/parts/sum-g3331/overview/make/plymouth

Since I've had a rocker-to-baffle interference problem in the past, that's why I put my hands on the valve covers. They didn't "feel" like I was getting any contact. Also, I set my valve lash 3/4 turn in (instead of 1/2 turn) to be sure I didn't have any "slop" in the valve train. The sound does seem to come from both sides.

Any more thoughts/ideas guys?
 
Beanhead is right the newer design of ramp is most likely the problem. The engine guy I asked for advise mentioned this.
Interesting his comment about different oils having little effect on the noise.
If the engine goes good perhaps try to forget about it like I did.
One thing I forgot to mention was with the hood shut you could barely make out any noise.
 
Well, I'm now running a comp cams XE274 cam & lifters and the engine does have headers & cheap, stamped valve covers. The valvetrain sure seems loud though.

Some history, I just replaced some factory valve covers. The valve train was noisy, I removed valve covers & saw contact marks on the baffles, so I removed the baffles. The engine was sucking oil through the PCV hose (had air compressor drier installed in PCV hose to verify), which is why I went to these cheap ones from Summit. They seem to fit/seal fine with Felpro cork gaskets.
View attachment 703148
https://www.summitracing.com/parts/sum-g3331/overview/make/plymouth

Since I've had a rocker-to-baffle interference problem in the past, that's why I put my hands on the valve covers. They didn't "feel" like I was getting any contact. Also, I set my valve lash 3/4 turn in (instead of 1/2 turn) to be sure I didn't have any "slop" in the valve train. The sound does seem to come from both sides.

Any more thoughts/ideas guys?
Just curious, do those covers have baffles?
 
I don't think there's really a difference in noise between adjustable rockers vs stamped, it's hyd vs solid lifters where there's usually a difference. That being said I've got a solid lift cam and Comp rockers and it's pretty darn quiet.
 
You didn't mention your cam, but if it's any sort of modern fast ramp design, they're noisy with either rocker arm. I would almost think, you could get them to be quieter with adjustables because you could adjust your lash some to quiet them down if desired? My old XE274 gives that 'sewing machine' sound... lighter oil, heavier oil, doesn't make much difference. That said, I'm not sure if it would be as noticeable with factory exhaust manifolds.
I have the XE268 and mine sounds the same. kind of worried me at first. I'm running 10w-40, too.
 
I'm running the Summit 6401 (298/303, Lift .466/.488) and Crane adjustables. They are semi quiet. More like a sewing machine than a typewriter.

I have my preload @ .020 Some run more .040 - .060
 
Comp XE lobes........ all the noise of a solid.

Only it doesn’t usually sound as good as a solid.

Hylift Johnson slow bleed(S suffix) lifters would be a little quieter.

My first experience with one was an XE284 shortly after they came out.
440-6 with ported 906’s and HS 1.5 rockers....... wow!! What a racket!!
 
Just curious, do those covers have baffles?
Yes, these valve covers have baffles. I have "considered" pulling off one side again to see if there are any rocker arm contact marks. I have since learned that you can just drill some holes in the baffles instead of removing them completely.
 
I'm running the Summit 6401 (298/303, Lift .466/.488) and Crane adjustables. They are semi quiet. More like a sewing machine than a typewriter.

I have my preload @ .020 Some run more .040 - .060
Well, mine is sounding more like an old typewriter with the Isky ductile iron rockers.
 
What procedure did you use to adjust the rockers?
 
What procedure did you use to adjust the rockers?
Followed the old Direct Connection valve adjustment decal. Start at TDC #1 firing and adjust one intake/one exhaust, rotate clockwise 45-degrees (I have degree tape on my harmonic balancer) & repeat.

At each 45-degree rotation, I loosened the appropriate adjustment nuts & backed off the screws. Then I rotated the pushrod with one hand, while I slowly turned the screw in, until I felt the pushrod seat in the lifter. Each time, I went in/out with the adjustment screw 3-4 times to be sure I had found the "zero pre-load", noted the direction of the adjustment screw, turned it in 3/4 turn & tightened the lock nut.
 
Auto Transport Service
Back
Top