[Cliff R]

"Funny how LS engines can run hydraulic roller lifters for 200,000 and more miles trouble free............."

GM started using HR lifters in the SBC's clear back in 1987 if memory serves me correctly. Have never once observed any type of failure with one. They are a completely different design than retro-fits AND I'll mention again that the spring loads on those engines are very light compared to what folks are running on these engines.

I've rebuilt several 4.3 and 5.7 Chevy factory HR engines with several hundred thousand miles on them and put the factory cam and lifters right back in them to go another couple hundred thousand miles or so. NEVER had the first issue with one to date.

So what are we missing here with this "retro-fit" stuff that they can't be whisper quiet and go the distance w/o issues?.........

[Murf]

I’ve lost track of the thread on adapting OEM rollers to Pontiac V8’s. Did anything every become of that? It seemed promising when I first read it.

Murf


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[GTOLou]

Originally Posted by Cliff R

"Funny how LS engines can run hydraulic roller lifters for 200,000 and more miles trouble free............."

GM started using HR lifters in the SBC's clear back in 1987 if memory serves me correctly. Have never once observed any type of failure with one. They are a completely different design than retro-fits AND I'll mention again that the spring loads on those engines are very light compared to what folks are running on these engines.

I've rebuilt several 4.3 and 5.7 Chevy factory HR engines with several hundred thousand miles on them and put the factory cam and lifters right back in them to go another couple hundred thousand miles or so. NEVER had the first issue with one to date.

So what are we missing here with this "retro-fit" stuff that they can't be whisper quiet and go the distance w/o issues?.........

I'm upgrading the cam on a 455 w/ aluminum heads spec'd by one of the larger Pontiac shops. I told them 100 times it was for a HR app. My mistake not checking them when I installed the heads.

I am finally upgrading the cam and the spring pressures are a VERY low. Under 100 closed. Its an older build - but no way it lost that kinda pressure over the years. Had to have been set up for Hflat tappet.

Anyway - except for some wear, the comp roller lifters seem fine to me. And this motor was always pretty quiet. I am not going to re-use.

Maybe going w/ pressures on the lower end of acceptable for HRoller is beneficial - IDK. All I know is that my lifter bearings "should" have been wrecked - and it doesn't seem that way...

[RocktimusPryme]

Is the moral of the story here to just take it easy on the springs with street/strip applications? If factory rollers are fine to at least the high 5000s with weak springs, why does a mild 462 need that much more seat pressure?

[Murf]

Originally Posted by RocktimusPryme

Is the moral of the story here to just take it easy on the springs with street/strip applications? If factory rollers are fine to at least the high 5000s with weak springs, why does a mild 462 need that much more seat pressure?

Heavy valve train?


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[steve25]

Years ago I had a Comp roller lifter fail the needles and it was getting large volume of oil!

Your failure is kind of strange though
Can you take a few close up shot of the roller axle hole on that failed side?

[chuckies76ta]

I've used these in a stroked 400 which I sold and is still running no issues. https://www.johnsonlifters.com/Produ...ST2112OPR.aspx . The lash has to be set properly though.

I currently am running Crower solid lifters on the hydraulic cam with no issues.

I have been told by the lifter manufacture no to run any oil heavier than 40w as it is to thick for the lifter action.

Charles

[FrankieT/A]

Originally Posted by Murf

Heavy valve train?


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Oldsmobiles take the same lifter, are they having these issues too.? I'm sure anybody with an Olds is changing to adjustable rockers.

Is it really not worth going back to the drawing board for this? What are we talking about here? A new CNC program?

[Formulajones]

Originally Posted by RocktimusPryme

Is the moral of the story here to just take it easy on the springs with street/strip applications? If factory rollers are fine to at least the high 5000s with weak springs, why does a mild 462 need that much more seat pressure?

Heavy valve train, which is why I like to take measures to install lighter parts.

Aftermarket camshafts that have some aggressive lobes require more pressure.

30 degree valve seats require more pressure.

There are quite a few reasons and probably more.

Typically, even with a soft closing ramp like the voodoo lobes, the hydraulic roller needs about 150 lbs. spring pressure on the seat and they run near 400 lbs. open. That's how the last few Pontiac Hydraulic Rollers were setup that I built with a custom voodoo roller and they are in service working fine.

Generally after some run time they'll loose about 10-15 lbs. seat pressure anyway so it's safe to say they are actually running around with 135-140 lbs. seat pressure, which isn't excessive on a hydraulic roller at all. No reason to be loosing needle bearings or breaking wheels with those kinds of pressures.

My 454 Chevelle has been in service with it's hydraulic roller and spring pressure like that for 20 years, never had a valve cover off of it. It's a pretty heavy valve train with 2.25/1.88 valves. It still spins to 63-6400 without skipping a beat and runs whisper quiet.

[Formulajones]

Originally Posted by tom s

If I was to not use Hyd roller lifters I would try a tight lash solid roller cam and lifters.Putting solids on a Hyd roller is a crutch and you loose about 8 degrees of posted duration and lift depending on what you set them at.I used to set mine at 6 thou.FWIW,Tom

I got dad away from the solid roller deal after his tight lash solid roller ate one. It was a Crower bushed roller with pressurized oiling too. Supposed to be the cure all. That didn't work. Lash was always spot on and spring pressures were good, set at 240 lbs. on the seat which is typical for a solid roller running on the street.

It locked up a roller and egg shaped it, ate the cam in the process. Crower had no explanation for it. Only had a few thousand miles on it.

So even going down this road isn't a 100% safe deal.

I think it's just the chance you take when building these engines with aftermarket high performance parts. The more aggressive you get the risk goes up.

[i82much]

what happens to my man card if i pull old faithful out of my 505 and put an 068 in?

[Formulajones]

Originally Posted by i82much

what happens to my man card if i pull old faithful out of my 505 and put an 068 in?

Oh no

[FrankieT/A]

Originally Posted by i82much

what happens to my man card if i pull old faithful out of my 505 and put an 068 in?

I'm thinking 041...

[RocktimusPryme]

Let me rephrase slightly. Is it a useful question to ask when putting together a top end "What is my lightest spring I can safely run to meet goals here?" And go with that spring.

On the surface to me it seems like having valve float slightly earlier than you want, is a better option than increased likelihood of catastrophic valvetrain failure.

This particular debate not withstanding, I have become a big believer that most classic motor builds probably run too much spring in general. No matter the cam type.

[i82much]

I hate the internet. I've been driving my car more than ever lately, I had more or less just accepted that I have a noisy valvetrain and was enjoying it. Now I'm in my shop staring at a box of new Isky EZ Roll pontiac solid roller lifters thinking I should tear into the thing and replace my Comp hydraulic rollers before something blows up.

I love this forum, but every time I come back and start reading again I convince myself that I need to start making changes to my car. Which, for once, is actually running pretty well and not causing me any problems!

[Steve C.]

'Valve float'.

If this situation occurs it has been said that if it continues after time the springs can further deteriorate to the point it can cause issues other than nosing over at rpm.



.

[Formulajones]

Originally Posted by FrankieT/A

I'm thinking 041...

That's not much better lol

[Formulajones]

Originally Posted by RocktimusPryme

Let me rephrase slightly. Is it a useful question to ask when putting together a top end "What is my lightest spring I can safely run to meet goals here?" And go with that spring.

On the surface to me it seems like having valve float slightly earlier than you want, is a better option than increased likelihood of catastrophic valvetrain failure.

This particular debate not withstanding, I have become a big believer that most classic motor builds probably run too much spring in general. No matter the cam type.

Like Steve mentioned, and several well known engine builders are in agreement with, that too light of spring pressure and valve float or bouncing off the seat is much worse than too much pressure.

And who's to say what is too much? In the grand scheme of things I don't believe that 10 or even 20 lbs. of pressure on the high side is going to do squat. Plus like mentioned, you have to consider where the spring is going to settle after a short amount of run time. They'll loose a bit of pressure anyway.

Case in point is dad's engine. When Paul spec'd that cam, the springs had a 1.91 installed height. So he had to find a spring that had his recommended 150 lbs. seat pressure, yet kept the open pressures in check. He wanted to see open pressures around 400 lbs. But when you have a set install height, and a certain diameter spring and guide to retainer clearances to work with, plus a retainer with a certain inner spring dimension you're trying to match, it limits your choices.
The closest he could come up with was 150 at the seat and 420 open. So that's how I set it up. It's been perfect, no noise, and runs right up to the 6200 rev limit dad has set on the box. Paul wasn't worried about the extra open pressure, he knew, and as I mentioned, with the lost pressure after run in they have probably settled right in line with what he wanted anyway.
Next time I have a valve cover off I'll check a couple of them.

[Steve C.]

I've mentioned this before, we pulled a few springs after a dyno session and one spring lost 14 pounds seat pressure. Another 11 pounds. Others slightly less and all from the batch of springs.


.

[RocktimusPryme]

I see the point, but I didn’t mean to purposely float your valves often. More that, if it noses over at 6100 then your shift point is below that. And that’s just for us that even race a little. How many of these engines never make a real pass in anger?

I’ve listened to the Drag Week guys talk about how much harder the road trip is on the NA cars. The boosted stuff doesn’t have to have the harsh radicals cam profiles with crazy spring pressures. We were just talking about factory setups with lighter springs that live forever.

It seems to me that no matter if it’s by lightening the valve train etc. if you can reduce the spring pressures it will at least help with a longer life.