Cam and follower tests.

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Extract from an article "What's In a Camshaft". Autor Kris Wieber. The Shop Magazine, Dec. 2, 2009 :

Another factor that contributes to camshaft performance [life, added by KS] is oil. The lubricity of oil has been a recent issue for nearly all manufacturers of internal engine components.
"Motor oil has changed over the years, mainly with the removal of zinc-phosphates (ZDDP). The reason for the removal is because today’s new cars have roller tappet camshafts. Roller tappet cams do not require these additives that flat tappet (hydraulic or mechanical) camshafts need. Flat tappet camshafts require this extra protection because the lifter slides across the cam lobe. This metal-to-metal contact between the cam and lifter will not last long without this additive, especially during ‘break-in,’" says John Steely, sales manager for Howards Cams.
There are specialty oil manufactures, such as Brad Penn, that have this additive, he notes. But most of the common name brands (including Shell Rotella) no longer have zinc-phosphates at all.
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Is this common knowledge?

-Knut

Well, It is for me.
Actually the roller follower in gasoline engines came about because of the catalytic converter.
The converter requires elimination of the heavy metals like ZDDP to prevent failure of the converter. Once the ZDDP was reduced then cam failures became common. [around 1980] The quickest fix by the manufacturers was the adoption of the roller follower which does not need ZDDP.
 
The followers went from design where the pad was simply brazed to the bottom of a flat steel body to a spiggoted design where the pad fits into a depression in the bottom of the steel body. This solved the problem of spitting the pads.

The change was made in the mid 80's as I recall.

So if you buy a new set of lifters from AN they will have the spigot? Do you have pictures of the differences?
 
So if you buy a new set of lifters from AN they will have the spigot? Do you have pictures of the differences?

Yes, they will be have the spigot.

They appear the same externally but if you look inside toward the bottom of the follower you can see the bronze colored weld around the inside bottom corner of the spigotted units.
 
Now to be fair someone running 45+ year old parts that take a serious pounding can expect occasional failures.

It’s nice that they are making improvements to the new parts.
 
Should a wary person have any follower they want to use tested for hardness?

After what I have seen recently, I would.

When using a case hardened billet cam like OEM or a hardweld buildup like a Megacycle or Webcam, I would want the follower to be at least 3 degrees harder than the cam.

I don't know the follower requirements for a chilled iron or a nitride hardened cam. Jim
 
Now to be fair someone running 45+ year old parts that take a serious pounding can expect occasional failures.

It’s nice that they are making improvements to the new parts.

Firstly, we're talking NEW parts here, not 45 year old parts. Secondly, They are not making improvements in this case. The followers are faulty. Simple as that.
 
Firstly, we're talking NEW parts here, not 45 year old parts. Secondly, They are not making improvements in this case. The followers are faulty. Simple as that.

As noted. Doesn't mean they can't be resolved in the future. I'm sure your heads were perfect every time. :rolleyes:
 
Jim,
You have a radius on your follower on your spintron video that you are testing for your next cam for your bike correct? what radius are you running? 3"- 4"radius ?
Cheers,
Thomas
 
Would putting a radius on a follower of the old style weld type increase the likelihood of a separation failure or no difference.
Cheers,
Thomas
 
Will these followers became available ? :D

I probably missed it in the video but are these hard faced followers only suitable for the Web Cam type camshafts or the stock material (1970's) cam's also ?
 
Got this bit of info back from T Prince re the cams he supplied me for the 1360 Vincent. The problems showing up with Norton's had me wondering about these cams, which are very high lift but looking good so far.

Seems the hardness difference requirement between cam and follower for Stellite has been known about for awhile.


"Hi Glen, How you going, My cams are case hardened EN36 62-64 Rock .40” deep the follower are 56-58 RH.

Stellite is funny stuff again the must be a difference in cam to follower hardness.
I used many stellited cams in the past. After a short time they looked like tram lines but did not wear any more.

The main reason why I started to make my own was when you weld old cams up they distort all over the place and the press fit is no longer good, by the time you have done all that the cost is more that making a new cam."


I'm assuming .40" deep is probably .040" deep.

Glen
 
All interesting stuff, but in this case, totally irrelevant.

I thought my post was relevant because I assumed Jim was removing the stellite and doing a hardweld build up on the follower to prevent the delamination possibility that I experienced. Maybe I was wrong...
 
I thought my post was relevant because I assumed Jim was removing the stellite and doing a hardweld build up on the follower to prevent the delamination possibility that I experienced. Maybe I was wrong...

You were right.

I was removing the original welded stellite pad from the non-spiggoted followers and replacing it with hardweld.
Both as a way to prevent delamination and to get consistent hardness.
 
Got this bit of info back from T Prince re the cams he supplied me for the 1360 Vincent. The problems showing up with Norton's had me wondering about these cams, which are very high lift but looking good so far.

Seems the hardness difference requirement between cam and follower for Stellite has been known about for awhile.


"Hi Glen, How you going, My cams are case hardened EN36 62-64 Rock .40” deep the follower are 56-58 RH.

Stellite is funny stuff again the must be a difference in cam to follower hardness.
I used many stellited cams in the past. After a short time they looked like tram lines but did not wear any more.

The main reason why I started to make my own was when you weld old cams up they distort all over the place and the press fit is no longer good, by the time you have done all that the cost is more that making a new cam."


I'm assuming .40" deep is probably .040" deep.

Glen


If there were cams available in the 62 to 64 range for a Norton then a 3 degree softer follower might work out OK, but I would be concerned about durability because of the small footprint of the Norton follower.
 
Will these followers became available ? :D

I probably missed it in the video but are these hard faced followers only suitable for the Web Cam type camshafts or the stock material (1970's) cam's also ?

I would not be making any followers available without quite a bit more testing in a real engine.
The idea is for hardweld cams or OEM type case hardened cams. I don't know how compatible they would be with cast iron or nitrided cams. I would just have to try it and see.
 
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