Prostar heads valve seal question

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93ragtop

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I purchased a set of prostar heads for a 2000 5.9 engine.
In the picture below, the seal on the right is the ones that came on the heads. The seal to the left, I have from a rebuild kit.
Is there any advantage in swapping the ones on the left on the new heads?
Also, could you look at the last picture. That is with one of the kit seals installed. It does not go flat at the bottom. Is that a problem
Thanks

20200703_180846.jpg


20200703_180648.jpg
 
You get a couple notions...from various builders... one is that the one on the left 'manley' looks like, is more a short term race seal that isn't super tight around the stem ,will control the oil but for how long...
The other ,thicker, tighter with more 'area' will control the oil for longer life.

Like a drag motor, refreshed every sum odd races or every season vs a service truck for the city going 200k. I remember speaking with different builders in the late 90's...and, well... I thought that might be bs. I mean..'expensive fancy brand name , gotta last right.. ' ? Nope.
The one seal I replaced with a Manley viton seal vs a thick black viton...the back of the valve was all gunked up more than the others. More oil was going down the stem/guide than the others... too much and incoming fuel air wont get as much off and it just builds like frosting on a cake.
Fact is..You'll always have 'some'...you have to have oil in the guide or it will overheat ,hog itself and or seize...but extra oil here isnt what you want.. if it doesnt have a bearing, it doesn't need more oil.
Point is...use the one on the right or go get the black viton seals from a local builder/machine shop...other thing is if they is ANY warranty...you'll void it by changing parts.
 
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The style on the left is like what comes on virtually every current production passenger car engine made.
 
The one on the left came in a "enginetech" gasket set.
Does it not quite setting flat make a difference?
 
Nope.
As long as it grips the guide boss pretty well.

It’s been a while since I had any factory magnum heads here, but I’m pretty sure that’s the style of seal that came on the heads as OE.

Looking in two parts catalogs, SBI and Fel Pro, that’s what they show for factory replacements.
 
Find a piece of pipe or tubing that fits over the seal and does not touch the spring and lightly tap it on with a hammer. It should go flush, more important to have it straight on the stem than flush.
 
mderoy340 said:
Find a piece of pipe or tubing that fits over the seal and does not touch the spring and lightly tap it on with a hammer. It should go flush, more important to have it straight on the stem than flush.
Click to expand...
I used to use a 12 point socket.
I think the seal sitting square on the guide matters and all the way flush with the top of the guide, doesn'thave to hit the bottom. In a far out scenario retainers smacking seals isnt good for anything involved. Plain and simple...crooked is lame. Aka I agree except for the flush part, or I would have hit the green button.
As for seal style.. being that we have some chiming in, I'd like to know if they are saying that is a better seal and why they believe that if so.
 
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I look at it this way.
The companies that have to warranty emission control systems on new vehicles for a rather long period of time have adopted the metal clad style of seal for essentially all production vehicles for probably well over 10 years.

It’s a 3 piece design, so it should be more costly to produce, and yet these companies that are using literally millions and millions of them annually have determined they are superior to the technology used before.

That’s good enough for me.

I bought a new Dodge Dakota in 1993 with the 3.9 Magnum.
I sold it a couple years ago....... never even had a valve cover off.
Still not smoking or using oil at 147,000 miles.
It should have had the metal clad seals as OE.

The old Mopars with the all rubber seals usually had the seals all crumbled up into pieces, and down in the oil pan long before you got to that point.

The only time I see issues with the metal clad style seals is if the seal isn’t really the correct one for the size of the guide boss, or it got mangled up during installation.

As for whether it will sit flush on the bottom....... that’s really just determined by how tall the guide is, and how deep the seal is.
If the seal is deep enough to sit flush on the bottom great.
But they often don’t. The inside of the seal touches the top of the guide, and that’s as far as they go.

I don’t feel it’s the only style of seal that can be used....... but I do use them on “most” heads.

I’m a firm believer in using what you’re having good luck with.
You like umbrellas? White Teflon? Ring and band? All rubber?
I’m not trying to change anyone’s mind....... just keep using them.

If I had bought those Prostar heads...... would I have run them with the seals that they came with?
Sure.
 
PRH said:
I look at it this way.
The companies that have to warranty emission control systems on new vehicles for a rather long period of time have adopted the metal clad style of seal for essentially all production vehicles for probably well over 10 years.

It’s a 3 piece design, so it should be more costly to produce, and yet these companies that are using literally millions and millions of them annually have determined they are superior to the technology used before.

That’s good enough for me.

I bought a new Dodge Dakota in 1993 with the 3.9 Magnum.
I sold it a couple years ago....... never even had a valve cover off.
Still not smoking or using oil at 147,000 miles.
It should have had the metal clad seals as OE.

The old Mopars with the all rubber seals usually had the seals all crumbled up into pieces, and down in the oil pan long before you got to that point.

The only time I see issues with the metal clad style seals is if the seal isn’t really the correct one for the size of the guide boss, or it got mangled up during installation.

As for whether it will sit flush on the bottom....... that’s really just determined by how tall the guide is, and how deep the seal is.
If the seal is deep enough to sit flush on the bottom great.
But they often don’t. The inside of the seal touches the top of the guide, and that’s as far as they go.

I don’t feel it’s the only style of seal that can be used....... but I do use them on “most” heads.

I’m a firm believer in using what you’re having good luck with.
You like umbrellas? White Teflon? Ring and band? All rubber?
I’m not trying to change anyone’s mind....... just keep using them.

If I had bought those Prostar heads...... would I have run them with the seals that they came with?
Sure.
Click to expand...
I agree on the metal clad part, now the spring band lip, which one? They can come in different colors, blue , red, brown like later factory, black..seemed to me there different tensions at contact point of the seal to stem. The density of the material as well. I'm skeptical because how do I know that one from other that look the same that have not done well.
If the the ones on the right are viton, fit tight on the guide and when new hold the valve in place all by themselves, I'd leave'em is my train of thought..especially if there is a lil more seal co tact area. The other ones maybe fine too. For what it's worth i quit using the teflon seals,like cranes, they wore the stems.
Between the 2 seals ..OP can use either n the diff will be something so small n far down the line it wont matter what it is if there is .
 
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teflon wears stems and shortly thereafter wear out
you got that right
Viton is much more expensive than teflon or rubber or silicone like the chevy trucks use
 
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