Re: Strange noise from cam area
[Re: varunner]
#2561950
10/10/18 03:02 PM
10/10/18 03:02 PM
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Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
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That's what I would do (what Zippy said), start with the bare cam/bearings & add items/recheck as you add: cam plate/lifters/t chain etc I'd think the moaning is scraping or rubbing from inadequate clearance or even possible an interference fit. EDIT with more thought the cam bearing/journal fit sure sounds like a likely culprit.
Last edited by RapidRobert; 10/10/18 03:12 PM.
live every 24 hour block of time like it's your last day on earth
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Re: Strange noise from cam area
[Re: varunner]
#2562309
10/11/18 06:12 AM
10/11/18 06:12 AM
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Joined: Jun 2014
Posts: 5,183
Porter67
master
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master
Joined: Jun 2014
Posts: 5,183
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Just re read your whole post, Ive had about the same trouble, your spring pressure might be flexing the cam or the core material is sub standard. Either way your probably gonna wear something out prematurely. IMO your near needing a billet core, at least thats what I ended up doing. Or what rockers are you running, have you inspected them? Ya got a vid of this moaning? Is it like "My legs caught in the combine" moaning?.... ummm "God im too drunk" type moaning? The wifes like "Thats it, thats the spot" moaning? We need a vid. Like CAB wrote, its talking to you but in what way? Or you could just make a vid of what you think it sounds like, like this. https://www.youtube.com/watch?v=nJIu4O-Jnfk BUT REALLY you seem to know its not natural. Last timing belt I put on, I couldnt follow the tensioner arrow and it was moaning letting me know I f-ed up and had I way too tight.
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Re: Strange noise from cam area
[Re: varunner]
#2562450
10/11/18 02:12 PM
10/11/18 02:12 PM
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Joined: Jan 2003
Posts: 14,531 So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
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So. Burlington, Vt.
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Way way before cams were nitrided, or tool steel lifters, or special polishing of the journals....... Look at what MP was recommending for springs for the .590, .620, .690 cams and what the open spring pressures were.
It was way more than 420 open.
I’m not saying those recommendations are right or wrong, but just think of all the motors that were built according to the MP manuals and ran those exact combinations of parts with no problems(or noises).
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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Re: Strange noise from cam area
[Re: varunner]
#2562451
10/11/18 02:16 PM
10/11/18 02:16 PM
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Joined: Jan 2003
Posts: 11,786 Portage,michigan
B3422W5
I Live Here
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I Live Here
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Posts: 11,786
Portage,michigan
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Coil bind possibly Checked all the pushrods closely to see if any are maybe bent a little
Last edited by B3422W5; 10/11/18 02:16 PM.
69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight 418 BPE factory replacement headed stroker, 565 lift solid cam, footbrake street/strip car Best so far, 10.32 1/4 1.41 best 60 foot 6.56 at 104.17
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Re: Strange noise from cam area
[Re: varunner]
#2562456
10/11/18 02:39 PM
10/11/18 02:39 PM
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Joined: Jan 2003
Posts: 14,531 So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
Joined: Jan 2003
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So. Burlington, Vt.
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I remembered something I did back before I knew any better.......
I had enountered a valve float type situation with a ssh-44 cam I tried. The motor had some Crower springs in it, and before I installed it I called and asked them if they felt those springs were adequate for the cam, and they said the springs should be fine. The motor would just flatten out, at an rpm quite a bit lower than what it did with the old Crower cam. I tried all kinds of things related to fuel and ignition, nothing made any difference. I brought the car to the local speed shop I was buying stuff from at the time and took the owner for a ride. He felt it seemed like valve float and asked me about spring pressures and installed heights..... which I couldn’t answer. He said to put some shims under the springs and see if it helped. I installed a .060 shim under each spring, and it totally fixed the problem.
About a year later I want to install a solid lifter cam, but it needs dual springs. I have some new heads to put on which already have the spring pads cut for the dual springs. I’m working at a parts store, and we sell TRW engine parts, so I look up some dual springs in the performance parts catalog for a 440. I thought....... hey...... if one shim was good..... two will be better!!
So I assemble the heads with my new dual springs and two shims under each one. There was no soft springing for cam break in..... i just fired it up and ran it at 2000+ for about 15 mins. No problems with break in. I ended up trying 4 different cams with the heads set up like that...... no problems with any of them. And the car ran pretty well too.
Years later when I’m working at a machine shop, I pull the heads apart for freshening. Everything was holding up fine....... and I had a chance to see how the springs were set up. As it turns out....... they were a pretty high rate spring. The highest lift cam I had run with them was around .550, and the springs were like 155 closed/450 open with that cam.
Sometimes ignorance really is bliss.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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Re: Strange noise from cam area
[Re: fast68plymouth]
#2562459
10/11/18 02:54 PM
10/11/18 02:54 PM
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Joined: Sep 2014
Posts: 4,457 Washington
madscientist
master
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master
Joined: Sep 2014
Posts: 4,457
Washington
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I remembered something I did back before I knew any better.......
I had enountered a valve float type situation with a ssh-44 cam I tried. The motor had some Crower springs in it, and before I installed it I called and asked them if they felt those springs were adequate for the cam, and they said the springs should be fine. The motor would just flatten out, at an rpm quite a bit lower than what it did with the old Crower cam. I tried all kinds of things related to fuel and ignition, nothing made any difference. I brought the car to the local speed shop I was buying stuff from at the time and took the owner for a ride. He felt it seemed like valve float and asked me about spring pressures and installed heights..... which I couldn’t answer. He said to put some shims under the springs and see if it helped. I installed a .060 shim under each spring, and it totally fixed the problem.
About a year later I want to install a solid lifter cam, but it needs dual springs. I have some new heads to put on which already have the spring pads cut for the dual springs. I’m working at a parts store, and we sell TRW engine parts, so I look up some dual springs in the performance parts catalog for a 440. I thought....... hey...... if one shim was good..... two will be better!!
So I assemble the heads with my new dual springs and two shims under each one. There was no soft springing for cam break in..... i just fired it up and ran it at 2000+ for about 15 mins. No problems with break in. I ended up trying 4 different cams with the heads set up like that...... no problems with any of them. And the car ran pretty well too.
Years later when I’m working at a machine shop, I pull the heads apart for freshening. Everything was holding up fine....... and I had a chance to see how the springs were set up. As it turns out....... they were a pretty high rate spring. The highest lift cam I had run with them was around .550, and the springs were like 155 closed/450 open with that cam.
Sometimes ignorance really is bliss. I agree. I'm not so sure that some of these issues occurring today with flat lifter engines is spring rate and load related. We all run longer, bigger valves, turn more RPM, with way more aggressive lobes than back in the day and we are still trying to run 350 over the nose. My current cam has 420 over the nose and I'm not having issues. I think the biggest thing is idle speed. I know most of the stuff I was doing in the early and mid 1980's had an idle speed of 1300-1500 and that was our street/strip junk. Today, guys want an idle speed of 750 max because that's where their Prius idles. I'm 255 at .050 and .620 gross lift. My can will idle at 750 without an issue. I don't let it, because that slow idle means the lifters rotate slower, the pump is producing less oil and everything is just grinding along. So I keep my idle at 1000ish and that's as low as I go. I learned a long time ago the biggest killer of roller lifters was cranking an engine over to build oil pressure (a serious no no) and low idle speeds. That came directly from Dan Jesel when I sent him a set of lifters to evaluate for one of my customers.
Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
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Re: Strange noise from cam area
[Re: varunner]
#2562463
10/11/18 03:21 PM
10/11/18 03:21 PM
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Joined: Jan 2003
Posts: 14,531 So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
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So. Burlington, Vt.
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About 15 years ago I freshened a set of 516’s a guy had been running on a 440 with the MP620 cam. I never saw the cam or lifters, but he said they looked fine, and he continued to run them after he got the heads back. I have no idea what springs they were, but they were set up at about 500lbs open...... and I set them back up like that.( Btw, using the specs from the load chart in the MP engine manual, the recommended spring for that cam shows 491lbs open load @.600 lift.)
Around that same time frame I was doing a fair about of dyno work for some guys that were building dirt track SBC motors. They were using fast rate flat tappet cams, and the first couple I ran for them had some pretty serious valve float issues. The cam supplier had told them to use their springs and set them up at around 130/330....... which just wasn’t getting it done.
The motors we built for that class were using springs set up more like 150/370, and they would rev about 1000rpm higher.
As to the OP’s strange noise....... IMO, it’s related to the cam bearing clearance and or material.
This is the test I would do...... Remove the spark plugs so the engine can be turned over manually as easy as possible. Verify you’re still hearing the noise. Then remove the distributor and drive gear...... install and run the priming tool, and see if the noise is decreased or eliminated(or if the motor seems to rotate easier) when there is oil pressure at the cam bearings.
I’d be trying to figure out if the noise was related to the cam rotating in the bearings, or the lifters rubbing on the cam.
Another thing that could be done is remove most of the pushrods. Say, all but one cylinders worth. This would greatly reduce the friction between the cam and the bearings, but the two remaining lifters would still be rubbing on the cam just as hard.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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Re: Strange noise from cam area
[Re: fast68plymouth]
#2562586
10/11/18 08:37 PM
10/11/18 08:37 PM
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Joined: Jan 2003
Posts: 14,531 So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 14,531
So. Burlington, Vt.
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As to the OP’s strange noise....... IMO, it’s related to the cam bearing clearance and or material.
With high spring loads the cam bends slightly, and if the bearing clearance is too tight to allow for this, the cam can start to bind in the bearing bores. It’s the same situation as when too light/thin of a wrist pin is used and it flexes in the piston pin bores and starts to gall the bores up. Sometimes you just need more room for things to move around.
This is the test I would do...... Remove the spark plugs so the engine can be turned over manually as easy as possible. Verify you’re still hearing the noise. Then remove the distributor and drive gear...... install and run the priming tool, and see if the noise is decreased or eliminated(or if the motor seems to rotate easier) when there is oil pressure at the cam bearings.
I’d be trying to figure out if the noise was related to the cam rotating in the bearings, or the lifters rubbing on the cam.
Another thing that could be done is remove most of the pushrods. Say, all but one cylinders worth. This would greatly reduce the friction between the cam and the bearings, but the two remaining lifters would still be rubbing on the cam just as hard.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123 Dealer for Comp Cams/Indy Heads
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