Engine builders/Gurus, I need your help.

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I know this is gonna sound odd and simple, but it's how I diagnose. (Odd and simple)
Have you tried a really thick oil in it and see if it changes the sound?
Like Valvoline 60 wt racing.
 
It's been a while, but we tried adding a bottle of Lucas oil stabilizer to it to see if that would do anything. This was on top of 20w-50. I don't remember if the tick got quieter, but I do know it was still there and loud.


Also, the tick does not get any quieter or louder as the engine warms up.
 
UOP,I vaugely remember some of the more aggressive Comp cams ramps doing similar sounds in Chevys.My .02 ¢
 
UOP said:
All we did was upgrade the intake, cam, heads, and valvetrain. The engine was in perfect working order before we did the upgrade, but we noticed the tick right away after idling the the motor down after cam break-in.
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The problem must be in the parts/areas that were changed out. If need be I'd change them all out one at a time if a visual of all of them (heads/intake/cam/valvetrain) reveals nothing obvious
 
Have you checked the engine bay or body for a source? I had a tick coming from the drivers side that I traced to the valve train but it turned out to be a screw hitting the back of the engine. Took me months to figure it out.
 
Rapid Robert said:
The problem must be in the parts/areas that were changed out. If need be I'd change them all out one at a time if a visual of all of them (heads/intake/cam/valvetrain) reveals nothing obvious
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It's something. We've eliminated everything with the heads, pushrods, and valvetrain. Must be something with the cam, that's the only thing left that we changed.

7dswinger said:
Have you checked the engine bay or body for a source? I had a tick coming from the drivers side that I traced to the valve train but it turned out to be a screw hitting the back of the engine. Took me months to figure it out.
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This we did try. Removed all accessories including the fuel pump. Checked all sorts of stuff. It's inside the engine somewhere.

needsaresto said:
Have you confirmed oil to both rocker shafts?
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Yes.

We're wondering if the lifters themselves aren't getting enough oil volume or pressure for some reason or another. There wasn't a tick with the old cam, so maybe the more aggressive lobe profile and/or higher spring pressure makes the difference between tick or no tick.
 
UOP said:
Got some news, though we still haven't figure it out. We decided to take the head off and take it to a machine shop to see if there was possibly something wrong with it, like a bad valve job or loose valve seat or something like that. Well, it came back with a clean bill of health. Looks like it's something in the shortblock somewhere, though it sure seems like a valvetrain issue.

I do have a question. What path does the oil take in a B motor? Just a guess, but is it oil filter -> oil pump -> mains -> cam bearings -> lifters -> rocker shafts? The reason I'm asking is I'm wondering if it's possible we're losing oil pressure to the lifters for # 6 and 8. I seem to remember when we swapped the cam that the cam bearings looked like they've seen better days. Is it possible oil pressure is bleeding off at the cam bearing, making it impossible for the lifter to pump up enough to hold up to the faster lift and spring pressures with this combo? The engine shows good oil pressure on the gauge (60+ cold, 20 @ hot idle), but maybe that's not the whole story.
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First off Comp XE grinds are noisy .

Oil path , pickup tube > oil pump > filter > passenger side main galley ... which feeds all the lifters > there is a path down to the main bearings > main bearing feed also feeds the cam bearings , #4 main feeds the #4 cam wihich hit and miss feeds the rockers > passenger side maingaley wraps around back of the block and feeds the drivers side galley.

Are your pushrods the proper length ? How much preload on the lifters ?
 
a couple of ideas to check look at the inside of the valve cover to see if the rocker is tapping the cover.ive seen this happen.also seeif the rocker shafts are on the properly as they can be switched side to side and flipped upside down and i believe can impede the flow of oil to the head

if a vale cover problem you can get a set of gaskets that are thicker.

just throwing a few ideas out there for ya
 
paul smart said:
a couple of ideas to check look at the inside of the valve cover to see if the rocker is tapping the cover.ive seen this happen.also seeif the rocker shafts are on the properly as they can be switched side to side and flipped upside down and i believe can impede the flow of oil to the head

if a vale cover problem you can get a set of gaskets that are thicker.

just throwing a few ideas out there for ya
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Good point on the valvecover but it appears to be tapping wihout the cover also . As far as the shaft impeding the flow , that won't happen . What happens is the rockers don't get oil to the high stress area where it needs it. It would be a good idea to pull the rockers and shaft and look for galling ?

I don't know if the hughes rocker is an alum body on the steel shaft , bushed , or full roller on the shaft ???
 
JohnRR said:
First off Comp XE grinds are noisy .

Oil path , pickup tube > oil pump > filter > passenger side main galley ... which feeds all the lifters > there is a path down to the main bearings > main bearing feed also feeds the cam bearings , #4 main feeds the #4 cam wihich hit and miss feeds the rockers > passenger side maingaley wraps around back of the block and feeds the drivers side galley.

Are your pushrods the proper length ? How much preload on the lifters ?
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Is the oil path listed for a small block? I'm wondering because of the oil filter location (rear passenger side for sb, front driver side for bb). But in any case, what you're saying is that the oil flow to the lifters have nothing to do with any of the cam or main bearings?

As for the pushrods, yes we believe they are the correct length. When the top-end upgrade was originally done it had adjustable rockers and we tried every pre-load between .25 turn to 2 turns with no change in this particular tick. Obviously at .25 turn the valvetrain was more noisy overall, but the main tick never changed.

Now that we've swapped to stock rockers and pushrods it's the exact same.
 
JohnRR said:
Good point on the valvecover but it appears to be tapping wihout the cover also . As far as the shaft impeding the flow , that won't happen . What happens is the rockers don't get oil to the high stress area where it needs it. It would be a good idea to pull the rockers and shaft and look for galling ?

I don't know if the hughes rocker is an alum body on the steel shaft , bushed , or full roller on the shaft ???
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The rockers definitely aren't hitting the valve cover. As for the Hughes rockers, they're aluminum (un-bushed), on a steel shaft, and as they aren't galled. The only blemish on them is my fault, and that's from when I accidentally tightened the shaft down with a pushrod out of alighnment.

bOb shingler said:
take the cam out and sell it.
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and then...............

500full.jpg
 
You could check to see if the timing chain or gears are hitting the block or cover somewhere. Also check alignment
 
I might be off base here, but just a thought. Would it be possible to measure the frequency of the tap, compare to rpm, and use that to narrow down the potential sources?
 
Just put the stock cam back in, no tap its the cam design. One more thing are those the recommended springs for that cam?
 
OLDSTYLE said:
You could check to see if the timing chain or gears are hitting the block or cover somewhere. Also check alignment
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I'll put that on the list.

Idaho said:
I might be off base here, but just a thought. Would it be possible to measure the frequency of the tap, compare to rpm, and use that to narrow down the potential sources?
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I dunno. I think that's a little over my head.

Purple Haze said:
Just put the stock cam back in, no tap its the cam design. One more thing are those the recommended springs for that cam?
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We think it's something to do with the cam, but not necessarily the camshaft itself. (Does that even make sense?)

The springs are box stock that come with 440source heads. Supposedly good to .600" lift.
 
UOP said:
Is the oil path listed for a small block? I'm wondering because of the oil filter location (rear passenger side for sb, front driver side for bb). But in any case, what you're saying is that the oil flow to the lifters have nothing to do with any of the cam or main bearings?

As for the pushrods, yes we believe they are the correct length. When the top-end upgrade was originally done it had adjustable rockers and we tried every pre-load between .25 turn to 2 turns with no change in this particular tick. Obviously at .25 turn the valvetrain was more noisy overall, but the main tick never changed.

Now that we've swapped to stock rockers and pushrods it's the exact same.
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Oil path is the same big block, small block and hemi , the mains are fed by the main galley , which runs thru the lifter bores and at the point where it feeds the mains it has a path to the cam bearings .

it is a little louder than I remember for a comp XE but I just went thru it with stamped steel rockers , I ended setting preload wit hthe intake and valley pan off , they are all within .010 of each other and the engine has quieted down , the cam is one of the smaller XE's though .

I'd still be looking for an EXH. leak ...
 
I just joined today, but I agree with looking for a crack in the flywheel, or flex plate. We just chased the same kind of noise in a 62, 372 impala. We tore apart everything top and bottom. Someone suggested the flywheel crack, and I thought they were crazy. Gues what! It runs very quiet now.
 
Idaho said:
I might be off base here, but just a thought. Would it be possible to measure the frequency of the tap, compare to rpm, and use that to narrow down the potential sources?
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I think this is a great idea. Valve train moves at half the speed of the crank. Anything exhaust related would also be at half the speed of the crank. Flywheel obviously spins at crank speed.

But how to measure the frequency?

Seems to me you could record the sound produced by the engine at a specific RPM, upload it to a PC and look at it with some kind of sound editing software. You should be able to see the ticks on the wave and compare the spacing with the timescale to get the ticks per minute compared to the revolutions per minute (RPM) that the file was recorded at.

Do you know any musicians?
 
is this a standard bore 383 because there could be an issue with the valve hitting the head or head gasket these heads will not fit a standard bore 383 unless you notch the top edge of the block.again my 2 cents and i had to notch mine
 
That's a good point, it is a .030" over 383. I wonder if that has something to do with it, but why in just that one spot?
 
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