Flat tappet lifters, wear patterns, cam lobe taper and other things. Let's swap opinions and ideas.

[OneWheelPeel]

I just moved the Coronet and heard what may be some lifter tick, I talked to a friend about lifters nowadays and even this thread and I started to wonder, has any company ever offered an "adapter" roller lifter that could drop in on a flat tappet cam? I understand some of how a flat cam is ground to encourage the lifter to rotate and that would have to be accounted for. Has anyone heard of such a thing?

 

[Ceedawg]

I just moved the Coronet and heard what may be some lifter tick, I talked to a friend about lifters nowadays and even this thread and I started to wonder, has any company ever offered an "adapter" roller lifter that could drop in on a flat tappet cam? I understand some of how a flat cam is ground to encourage the lifter to rotate and that would have to be accounted for. Has anyone heard of such a thing?

Won’t work, 2 different principles

 

[Geoff 2]

Unbelievable.
What's the old saying....you can lead the horse to water, but you cannot
make it......

 

[Kern Dog]

I just moved the Coronet and heard what may be some lifter tick, I talked to a friend about lifters nowadays and even this thread and I started to wonder, has any company ever offered an "adapter" roller lifter that could drop in on a flat tappet cam? I understand some of how a flat cam is ground to encourage the lifter to rotate and that would have to be accounted for. Has anyone heard of such a thing?

Unfortunately, no.
The lobes of the flat tappet cam have an angle to them. It is known as lobe taper. The angle is supposed to only be 1.5 to 2 degrees. Unfortunately, the wheel of a roller lifter wouldn’t ride squarely on the lobe.

 

[OneWheelPeel]

Unfortunately, no.
The lobes of the flat tappet cam have an angle to them. It is known as lobe taper. The angle is supposed to only be 1.5 to 2 degrees. Unfortunately, the wheel of a roller lifter wouldn’t ride squarely on the lobe.

I was picturing the roller would have a corresponding taper. I’m not so much asking about feasibility and more if there were products that attempted it that anyone heard of. Like one of those things that shows up at sema one year and is never seen again.

 

[Geoff 2]

I know some brands of roller lifters have a crown on the roller wheel. I am not sure if all of them have it. The crown ensures the load on the wheel is distributed evenly across the width of the wheel.

 

[Ceedawg]

I was picturing the roller would have a corresponding taper. I’m not so much asking about feasibility and more if there were products that attempted it that anyone heard of. Like one of those things that shows up at sema one year and is never seen again.

The roller is always centered to the lifter, cam is made to induce lift from center. It rolls up the ramp. Non roller lifters start to lift from the outside edge of lifter (on the ramp face) then move to the center then back to edge. Because of the taper on lifter and on cam lifter never rides on its whole face, if it does it’s wiped. One reason mopars bigger lifters are better over the other brands (smaller diameter) mopars mushroom lifters were designed so as to have more lift and duration then conventional ones (NASCAR mainly because they were not allowed to use roller cams).

 

[Geoff 2]

More wrong info from Ceedawg in post #107. Non-roller lifters do NOT ride on the outside edge of the lifter.

The crown on the lifter together with the slight side to side taper of the lobe [ 0.001-2" ] means the contact point is inboard from the edge of the lifter. What spins the lifter to minimise & distribute wear is the fact that the centre line of the lobe is offset slightly from the centre line of the lifter.

 

[Ceedawg]

More wrong info from Ceedawg in post #107. Non-roller lifters do NOT ride on the outside edge of the lifter.

The crown on the lifter together with the slight side to side taper of the lobe [ 0.001-2" ] means the contact point is inboard from the edge of the lifter. What spins the lifter to minimise & distribute wear is the fact that the centre line of the lobe is offset slightly from the centre line of the lifter.

View attachment 1754057

What is wrong with you? Are you an idiot that just loves to stomp around claiming you’re the best?
Nothing I’ve said is wrong especially the part about circumference measurements or the ‘edge’, lifter cant turn from center. WHY do the Chevy guys want the bigger diameter Mopar lifters? To ride in close proximity of the center? Now IF your picture is showing how they make lifters and cans now, there is the problem of wiped cams. Please educate yourself before spewing out stuff you read on the internet. BTW look at any wiped lifter, is the ‘bowl’ in center over does it cover the entire face? Look at the wear pattern of any old cam, on the edge back to center. I’ll agree lifter is not all the way to edge but it’s farther out than that generic picture you put up. Cam placement in block is another issue for further dissusion.

 

[Geoff 2]

Ceedawg,
I am not the idiot. Have a look at how many ticks your posts are getting........
You are making wrong statements. Get it? I am correcting them so that others do not absorb your faulty advice.
I don't need to 'read the internet', as I was building engines & fault finding looooong before the i'net arrived.
Don't write rubbish & then nobody will question your info. Grow up!

 

[DeltaV]

I used to think that all camshafts were hardened. I was surprised to learn that they were not.
Many years ago, Comp Cams advertised of a process they offered known as Pro Plasma:

Your statement (not hardened) and example (which is hardening) is confusing...not sure what you're trying to say.

The Pro Plasma process is their method for nitriding the material which is used for hardening...

4.2 Nitriding​

Nitriding is a surface hardening process where atomic nitrogen is introduced into the surface of a ferrous alloy. There are several different nitriding processes such as gas, plasma, and salt bath nitriding.

Since nitriding does not require quenching, and due its low temperature, generally between 500°C and 580°C, this surface hardening process produces components with much less distortion than carburising. Due to this, nitriding can be performed on finished components. Depending on the process parameters, a nitrided zone will be generated in the material, which is often divided into the compound layer and diffusion zone. The compound layer consists mainly of iron nitrides, with a thickness that can reach tens of microns. However, the compound layer will not always be present and will be dependent on the alloying elements, time, and temperature of the process. The diffusion zone, on the other hand, can be as thick as several hundred microns and can be described as the original microstructure with some solid solution and precipitated nitrides [29].

The main objectives of nitriding are to increase the surface hardness of the material, as well as its wear resistance, fatigue life, and corrosion resistance [30], which are achieved by the presence of the nitrided layer. The hardness of the nitrided layer can be higher than that achieved by carburising and is in the range of 800–1200 HV.

https://www.sciencedirect.com/topics/engineering/nitriding-process#:~:text=The main objectives of nitriding,presence of the nitrided layer.

______________________________________

COMP Cams developed the process of ion nitriding for camshafts, or Pro Plasma Nitriding.[9] This is a 36-hour process that uses pulsed nitrogen plasma in a vacuum controlled environment to embed chains of nitrogen ions into the camshaft surface approximately .008” - .010” deep, significantly hardening the surface.

Ref:
Fisher, Rob. "Engine Lubricants - Solving The Flat-Tappet Puzzle". Circle Track. Interlink Media. p. 3. Retrieved 2008-09-29.

 

[Kern Dog]

My point was that I was under the impression that as part of the manufacturing process, I thought that camshafts and lifters were somehow treated with some measure of protection. I assumed that all camshafts were done this way, OEM and aftermarket. Once I learned that they were not, I was surprised. Sometime later, I read about this "Pro Plasma" treatment that Comp Cams was offering.

 

[DeltaV]

Once I learned that they were not

Got an example or a link?

 

[Kern Dog]

To what?
I was told something like 20 years ago that camshafts and lifters are just untreated metal. Is that disputed now? Are you refuting that?

 

[DeltaV]

I was told something like 20 years ago that camshafts and lifters are just untreated metal

Told by an expert? Got an example of just untreated metal?

 

[Kern Dog]

Magazine articles, word of mouth, internet forums, etc. It was so long ago, I don't remember. I don't remember who taught me how to change a tire.
Where has it been stated that camshafts are actually hardened? Are you asserting that they actually are?
If I'm wrong, I'm okay with it. I don't recall anyone else in this thread or elsewhere disputing this topic.

 

[RemCharger]

Camshaft hardening myth? - Don Terrill’s Speed-Talk

 

[Kern Dog]

Well, son of a bitch.....



This is yet another shock to me.

 

[Kern Dog]

Dang....It was so long ago, I really don't remember where I "learned" that regular flat tappet camshafts were just cast iron. This belief was supported by instances of worn off lobes. Hey, if a part is heat treated, that wouldn't happen, right? It has been maybe 25 years now that I thought that cams were just machined and shipped out to be put into use. The topic never came up for discussion to prove me wrong in all that time like it just did here.
It would explain how camshafts are able to survive in their high stress environment.

 

[DeltaV]

Chilled steel or chilled iron casting process was used in the 1950's in the mass produced automotive world.

Speaking of the automotive world, @RJRENTON can probably provide a short historical perspective on materials & processes used for surface hardening of "lifters" and camshafts.