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Valve Train Issues

Did the shop that installed the cam bearings have your cam on hand for test fitting?

Stock BB Mopar blocks can often be a PITA to get the cam bearing clearances correct on.

How does the bottom of the lifter that goes along with the short cam lobe look?

I doubt this caused your problem with the cam, but I’d say “most” of the hyd lifters sold by Comp are made by Hylift Johnson.

Their preload recommendation is(taken from their website):

“How much preload is right? The Hydraulic lifter only needs a small amount of preload. This preload is just to take up any lash in the system and then to remove any contact between the internal components of the lifter and the retaining ring. We only recommend .020” to .040” of preload on any of our lifters.

Since it sounds like you’ve already had a failure, I’d suggest you have the replacement cam nitrided.
Unfortunately, I don’t believe Comp sells any BB Mopar cams nitrided as an “off the shelf” option.
Meaning, it’ll be priced as a custom, with the nitriding as an extra cost option.
 
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Did the shop that installed the cam bearings have your cam on hand for test fitting?

Stock BB Mopar blocks can often be a PITA to get the cam bearing clearances correct on.

How does the bottom of the lifter that goes along with the short cam lobe look?

I doubt this caused your problem with the cam, but I’d say “most” of the hyd lifters sold by Comp are made by Hylift Johnson.

Their preload recommendation is(taken from their website):

“How much preload is right? The Hydraulic lifter only needs a small amount of preload. This preload is just to take up any lash in the system and then to remove any contact between the internal components of the lifter and the retaining ring. We only recommend .020” to .040” of preload on any of our lifters.

Since it sounds like you’ve already had a failure, I’d suggest you have the replacement cam nitrided.
Unfortunately, I don’t believe Comp sells any BB Mopar cams nitrided as an “off the shelf” option.
Meaning, it’ll be priced as a custom, with the nitriding as an extra cost option.

We had to polish 0.003" off two of the cam journals to get it to fit right initially. It was too tight at first. After that it seemed to spin freely by hand. They didn't seem to be concerned about the 0.019" wear on one cam lobe and told me to keep running the cam. They also told me to buy OEM style lifters from (johnson hylift) this time, I had comp high energy lifters previously. One lifter had started to make a flat spot and two others dont seem to stay pumped up even after priming them on the bench. When I called comp they told me 0.020"-0.080" pre load, thats also in the instructions provided. As far as "nitriding", I had never heard of that until just now, I had to look it up. Comp will do this as an extra cost I assume?
 
I've come across a couple big blocks with valve train noise using Comp lifters. After a good parts inspection, I replaced with Crane anti-pump up lifters that solved the issue.
 
They also told me to buy OEM style lifters from (johnson hylift) this time, I had comp high energy lifters previously.

I think if you called Comp, you’d find the HE lifters(822-16) are OE style Hylifts.

Although, they may also have other sources for them.

If your motor eats that failing lobe and ingests all that metal and ruins a bunch of parts, is that shop going to rebuild the motor for you?
 
I think if you called Comp, you’d find the HE lifters(822-16) are OE style Hylifts.

Although, they may also have other sources for them.

If your motor eats that failing lobe and ingests all that metal and ruins a bunch of parts, is that shop going to rebuild the motor for you?
Good point.......they probably would not.
 
I recently rebuilt my 440, engine has stealth heads, comp lifters, comp cam, and stock stamped rockers. I did the cam break in without much trouble. Drove the car for about 10 min. Parked it and all of a sudden got a bunch of valve train noise. When I run the rpms up, it stops. I pulled the valve cover, the rocker bolts are tight. I set the preload at 0.070", by using a length checker and buying push rods that fell between 0.020"-0.080" recommended by comp. The rockers are slightly loose, you can move them side to side. And I can push some of the lifters in by hand, like they aren't pumped up. I didn't soak them first, but they should be pumped up after running awhile. I'm certain that's the issue. I primed the engine before I started it. What should my next step be?


How much wear was present in the Blocks Lifter Bores in the area below where the Oil gallery intersects ?
You know.... the ~.250" to .300" load area below the Oil gallery in the Lifter Bore ?

What was the V/Spring Seat and OPEN Loads on the Stealth Heads as installed ?
 
I guess I didn't notice any "wear" that caught my eye when I pulled the lifters out . At least nothing that stood out. I'm not sure what the loads are.
 
I guess I didn't notice any "wear" that caught my eye when I pulled the lifters out . At least nothing that stood out. I'm not sure what the loads are.

That's one of the problem areas on these 40-50 years old blocks with 100's thousands of miles, when contemplating a Hydraulic Flat Tappet Cam rebuild ?
or,
a Hydraulic Roller deal ?

If you ever get the chance on a HOT engine, pull the Dizzy and run a primer with a Borescope down the Lifter Valley..... watch the Oil Pressure PISSING out the bottom side of the Lifter backside by the Oil Gallery. I know pressure is supposedly to be "pressure" in a closed system.... but that's the only common denominator we've found with Flat Tappet tics/noisey Lifter bleed downs.

If there is wear in that small area, for whatever reason, in our experience only anyways, the Hyd Lifter may not see sufficient Oil Pressure to maintain pump up against the V/Spring loads, yes, even a lowly F.T. type spring depending on how much wear = bleed down and V/Train noise.
On the Stealth's, we typically don't run anymore than ~120 Seat and well under 290# open for Hyd Flat Tappets, which is very safe for Cam Run-in with Zinc in the Oil, and really..... you don't need anymore with most of the .842" Dia Lifter Cam Grinds like your Thumpr deal.

When we see anymore than .0005" wear below the Oil Gallery in the Lifter Bore and above .0016" clrc in the Bore itself ?
For budget street stuff we automatically:
Re-Do the Stealth V/Seat Angles with our own multi-angle, and place the V/Tip UP out of the Head on the topside from the V/Spring seat pad to around 2.145" to 2.160" to raise the V/Spring installed Ht(lower Pressure).
A quick Bowl blend where our seat cutters stop after that.... and That's it, That's all with a Back-cut Valve.
and
Tighten our bottom end Oil clearances to .0026" to .0028" Mains(requires Line Honing to set the Brg Clrc), and Rod Clrc to .0024" to .0026", which using the M63HV and 10-40 or 15-40 Oil provides Hot Idle Oil Pressure of 45 psi and running at relief of 77-80 psi

Long story short here...
we see wear in the Lifter Bore we:
* UP the Oil pressure
* Mill the Block(10.71") & Heads(.020") to provide .100" + Lifter preload on the stock Stamped Steel Rockers in conjunction with our Tip Ht/Seat Angles upgrade.

Dyno'd one again yesterday, .030 over 440, ICON 9953 Pistons, STEALTH Heads as above,(NO Intake or Opening Porting just the Bowls),ARP Rod Bolts, Comp XE284H FT Cam, 10.14:1 C.R., Holley Street Dom & 850 Carb, Stock Stamped Rockers & Pushrods.
504hp @ 5,400 rpm and 525 Ft/Lbs
WITH....
the Big oval N96 6-Pack style 4 BBL Air Cleaner installed.

Quiet as a tit mouse !
Problem free Cam run-in !
 
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Did the shop that installed the cam bearings have your cam on hand for test fitting?

Stock BB Mopar blocks can often be a PITA to get the cam bearing clearances correct on.

How does the bottom of the lifter that goes along with the short cam lobe look?

I doubt this caused your problem with the cam, but I’d say “most” of the hyd lifters sold by Comp are made by Hylift Johnson.

Their preload recommendation is(taken from their website):

“How much preload is right? The Hydraulic lifter only needs a small amount of preload. This preload is just to take up any lash in the system and then to remove any contact between the internal components of the lifter and the retaining ring. We only recommend .020” to .040” of preload on any of our lifters.

Since it sounds like you’ve already had a failure, I’d suggest you have the replacement cam nitrided.
Unfortunately, I don’t believe Comp sells any BB Mopar cams nitrided as an “off the shelf” option.
Meaning, it’ll be priced as a custom, with the nitriding as an extra cost option.

We've had great success on Hydraulic F.T. Lifters running the Hyd Lifter Plungers much more compressed, like .100"+ and NOT leaving much room for the plunger to compress at all.
And we've talked to Comp Tech at length around rpm break-down with their HR Lifters as well.... the cure for us once again was to run down the Plungers leaving FAR less for them bleed down against the HR's much higher V/Spring loads.
When push comes to shove on the phone.... Comp tech agrees .130" preload on their HR's is fine(it has .165" travel), be dammed if the .030" extra can bleed down sufficiently to cause higher rpm dud power, yet it will still fill with enough Oil to run quiet.
 
So by adjusting the pre load on the lifters more, the sewing machine sound goes away?
 
So by adjusting the pre load on the lifters more, the sewing machine sound goes away?

That's what has worked for us, your results may vary.
With stock stamped rockers we plan/do it during the Block/Head Machining, then 1 mock-up before setting final Seat Angles/V-Tip Hts.
or,
I suppose a DIY guy using stock stamped rocker arms, if he has Comp Cams 10* Retainers/Locks that accept them, could install V-Tip lash caps for an extra .040" Lifter compression(.060" thick on the V/Tip = .040" at the lifter plunger on 1.5 RR).
Just say'in....
if you are already running and sounding like a "sewing machine" ? might be a viable inexpensive option to try more plunger compression with Lash Caps, but obviously you should CHECK first to see how much is there beforehand ?
 
And this method has the potential to work with adjustable rockers?
 
How many turns would you tighten from zero lash on adj rocker arms? To get the .030 plunger height? Nodular iron rockers.
 
I have always been leery of Comps lifters since they are usually noisier than most. So when I upgraded the cam in my stock 383 recently I wanted to use the old MP "Hemi Grind" cam. I looked at the specs and wasn't wanting a 108 CL so saw Comp had the newer version in their "Nostalgia Cams" with 110 CL. After
some reluctance went for it. After a proper break-in all seemed fine but it had the dreaded slight lifter noise they are known for. I took the car for a 10 mile ride and then after about an hour restarted it and valve tap bigtime!! I thought it ate a lobe. Took off VC and found #2 exhaust lifter wouldn't stay pumped so replaced it and all is fine again. In the back of my mind what's going to stop another lifter from premature failure so next time the covers are off (hopefully never) I will change out all the lifters with a Crane or other quality brand.
Ron
 
That's one of the problem areas on these 40-50 years old blocks with 100's thousands of miles, when contemplating a Hydraulic Flat Tappet Cam rebuild ?
or,
a Hydraulic Roller deal ?

If you ever get the chance on a HOT engine, pull the Dizzy and run a primer with a Borescope down the Lifter Valley..... watch the Oil Pressure PISSING out the bottom side of the Lifter backside by the Oil Gallery. I know pressure is supposedly to be "pressure" in a closed system.... but that's the only common denominator we've found with Flat Tappet tics/noisey Lifter bleed downs.

If there is wear in that small area, for whatever reason, in our experience only anyways, the Hyd Lifter may not see sufficient Oil Pressure to maintain pump up against the V/Spring loads, yes, even a lowly F.T. type spring depending on how much wear = bleed down and V/Train noise.
On the Stealth's, we typically don't run anymore than ~120 Seat and well under 290# open for Hyd Flat Tappets, which is very safe for Cam Run-in with Zinc in the Oil, and really..... you don't need anymore with most of the .842" Dia Lifter Cam Grinds like your Thumpr deal.

When we see anymore than .0005" wear below the Oil Gallery in the Lifter Bore and above .0016" clrc in the Bore itself ?
For budget street stuff we automatically:
Re-Do the Stealth V/Seat Angles with our own multi-angle, and place the V/Tip UP out of the Head on the topside from the V/Spring seat pad to around 2.145" to 2.160" to raise the V/Spring installed Ht(lower Pressure).
A quick Bowl blend where our seat cutters stop after that.... and That's it, That's all with a Back-cut Valve.
and
Tighten our bottom end Oil clearances to .0026" to .0028" Mains(requires Line Honing to set the Brg Clrc), and Rod Clrc to .0024" to .0026", which using the M63HV and 10-40 or 15-40 Oil provides Hot Idle Oil Pressure of 45 psi and running at relief of 77-80 psi

Long story short here...
we see wear in the Lifter Bore we:
* UP the Oil pressure
* Mill the Block(10.71") & Heads(.020") to provide .100" + Lifter preload on the stock Stamped Steel Rockers in conjunction with our Tip Ht/Seat Angles upgrade.

Dyno'd one again yesterday, .030 over 440, ICON 9953 Pistons, STEALTH Heads as above,(NO Intake or Opening Porting just the Bowls),ARP Rod Bolts, Comp XE284H FT Cam, 10.14:1 C.R., Holley Street Dom & 850 Carb, Stock Stamped Rockers & Pushrods.
504hp @ 5,400 rpm and 525 Ft/Lbs
WITH....
the Big oval N96 6-Pack style 4 BBL Air Cleaner installed.

Quiet as a tit mouse !
Problem free Cam run-in !
Good info, after reading that I realize I don't know anything about this. This is the first motor I've put together myself, wish I had known some of that before I got to the point I am. Dumb question, I bought some OEM style lifters from sealed power. They don't have an oil through hole like the comp high energy lifters do. I'm running solid pushrods. Could that have caused some of my lifter bleed down issues? When I took this engine apart it had oil through pushrods, even though it has stock rockers
 
If you bought Sealed Power HT-976’s, those are the correct BB style lifter(68 and newer) with the high thin oil band and no pushrod oiling.
Stock pushrods are solid, so no need to oil thru the lifter.
 
If you bought Sealed Power HT-976’s, those are the correct BB style lifter(68 and newer) with the high thin oil band and no pushrod oiling.
Stock pushrods are solid, so no need to oil thru the lifter.
Yeah that's what I bought
 
Did they come in little “4 packs”?

Did it happen to have a country of origin on the box?

The reason I ask is, I recently saw some Sealed Power Chevy lifters that were made outside the US.
 
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