Wiped Cams

So a member here was interested in my old Mopar Performance / Direct Connection 509 cam. I ran this cam for a short while in the 80's in a stock bottom end 440 with home ported 906 heads (I did not do good work back then). In race trim the 67 Coronet went 11.70's. I was happy. Then I built a new motor and this cam stayed in the short block for decades. I had run 20w-50 Kendall oil in it.

I take the cam off the shelf and it looks purty darn good till I measure the lobes in the lathe. Its really bad. When I really looked at it close I could visually see some rounded lobes - at first glance I missed it.

Fast forward a few months. I find another 509 cam hanging in the garage. No idea where it came from but its been there around 25 years - that's when I put the shelves up and tucked the cam away. It looked even better. Back in the lathe and lo and behold 2 wiped lobes. One 0.036" and the other 0.062". WTH?

I always thought I was totally successful with my hydraulic cams back in the day. My paradigm is shot. Anyone else have similar experiences on old school cams and oil? Here I thought it was just a new era phenomenon............ I have a couple more used cams in the basement. I will measure those too just to see.

I have a 509 from about 30 years ago that a friend ran for 2 seasons of bracket racing.
I don’t know what he ran for springs, but probably the 933 springs, which are a pretty high rate spring, that don’t have a lot of extra space til coil bind if installed at the stock 1.860 installed height and opening to .500” lift.
If the installed height is a little short, I can see that leading up to accelerated wear.

It was given to me, I looked it over quick....... saw nothing obvious at that time.

If I get a chance I’ll measure it up this weekend.

I mark my pushrods and make sure they are spinning while rolling the crank. I'm told the lifter is always the cause of wiped cams and the cam has nothing to do with it. Howards also told me nitrating is a waste of money and someone just taking your money because of this. check your lifters and make sure they spin while cranking. EDM lifters with good oil high in zinc and phosphate as well.

Absolutely, positively........ not true.

If the cam is ground with inadequate lobe taper, causing the lifters to not turn...... how is that not a cam problem?

I’ve seen that situation many many times.

Or the guy over on FABO that had the SBM Hughes cam(ground at Howard’s) that had .007(7 thou) lobe taper that had the lobes chipping away from the edge loading.
Again...... not a lifter problem.

This lifter came off a hyd cam that had under a half thou lobe taper:
No taper...... no spin.

Can we invent a lifter with an oil band turbine so it rotates on the base circle no matter what

Looks like lifters should always be checked. https://youtu.be/9EBsMqqu8Bo
I believe what the gentleman at Howards was saying is a cam with a good core and properly machined would not be the fault of its own if it lost a lobe. The gentleman i spoke with said he built and raced pro stock motors, so i took him on his word.

Uuuhh....... seems like a “Captain Obvious” statement to me.

A properly machined cam made from a casting with the correct heat treat won’t go bad on its own??
Huh.

Well, I had a post all typed out about the 509 cam..... and poof..... it disappeared before I could enter it.
I’m not typing it out again and the new shorter version is.......

It’s not a 509 cam after all...... looks like it’s a 484 cam.

Lobe lift varies about .006”, even when measured in areas of the lobe with zero wear.

The wear pattern doesn’t go all the way across of the nose of the lobe.

I checked several lobes for taper...... they’re right about .0015”.

this statement should read " IF THE LIFTER DOESNT SPIN , FAILURE IS COMING QUICKLY" !! it is a good idea to make sure their is rotation in the lifters ......

I went roller instead of hyd flat tappet because of all the flat cam lobe drama.ive talked to a ton of people about cams in the last 2-3 months,and the consensus is insufficient taper on the lobes. General opinion seems to be they need .003 out of the box?

taper is on both the cam and lifter faces... tool steel lifters can fix a lot of this.....

Yep, who makes/grinds that cam? Do you know if nitriding would have saved that cam lobe?

If you’re referring to the cam in my pic...... it doesn’t look good in the pic, but that lobe is perfectly fine.
As are all the others.
The brighter area on the left is untouched by the lifter.
The lift on both sides of the lobe is within .001”.

The color of the cam and lack of parkerizing should be a dead giveaway as to where it came from.

Ok, well thats interesting. I would say it's a purple shaft, but i never ran one. I know nothing about them.

Lifter is supposed to be flat, taper on the cam. That’s why the lifter turns. I think another problem is the cam load center has to be on the outside of lifter (cam to far in or out) to close to the center it’s harder to turn. Look at the cam in the hole, roller dead center, solid-hydraulic offset. imo

Lifter should be Convex, & cam ground on a taper

Exactly.

I call bs on that

Hilarious.

The fact that the lifter faces aren’t flat is common knowledge.
It isn’t some new revelation.

Here’s a pic from the old DC engine manual from the 80’s:

Sorry, cudaman, but you are wrong, no BS... the name "flat tappet" is a misnomer anyway. There is about a 30 inch radius on the curvature, pretty much impossible to see with the naked eye over a .904" diameter, but it is there.

The usual test is to put two lifter bottoms together and they should rock, since they are both convex. That will also let you see the gap as you rock them.

Sorry Didn’t see the ‘exaggerated view’

http://toplineauto.com/wp-content/uploads/2019/04/Lifter-Application-Catalog.pdf

Page 6

[align:right][/align] roller cams must use a thrust button. they will walk out of the front of the block without one. they have no taper ... a flat tappet, whether solid or hyd. has the offset ground in them that keeps them in the block and spins the lifter on the cam. if the lifter stops turning , they both will gall and fail even with the best motor oil in the world. I will bet 99 % of all failures are due to this. the more rare event is bad metal in the cam or lifter... and a good set of matched tool steel lifters will prevent that . they cost more but , you can swap them into any hole on any cam over and over ... if you don't want a failure , check all the parts for correct tolerance - lifter bores too. just be certain they rotate ..

i thought the only lifters able to be swapped cam to cam, and hole to hole were the shubeck's ?
even being tool steel, i would think each lifter would wear the cam lobe [at least] to the way the bore was machined.

AND as I have said before, NO Tool Steel lifters for me ever again on the street.

Didn't I read somewhere that extremely hard lifters (Schubeck or tool-steel) will cause that same work-hardening and flaking of the cam nose?
Doesn't sound like a good idea for street use...

I have a Howards FT in my 360. I am a little worried we went a bit nuts with the seat pressure, as I am not sure how great the lobes look now. I might check the lifters before it goes on the dyno again, it's been sitting for a long time.

years ago trend performance was working on this... if you get the correct parts ,it has been done. I have done it on circle track engines that had some lobe profiles that were considered impossible ... to live long if at all ! any seat pressure over 135-140 was asking for it...I went by that rate quick ! the cam and lifter must match. you can get tool steel lifters uncoated for std. type cams but the ultimate trend perf. lifter will live on a tool steel cam ! this link if it will work , should be saved for all the wiped lifter questions... it has a good grasp on how cams and lifters interact . also at one time you could have the lifters re-ground/polished to restore them to new !! ----EK3 https://blog.trendperform.com/inside-the-highest-tech-flat-tappet-lifers

And I did all of this, Trend Lifters & it was an VERY expensive lesson.

you wiped lobes ?? or lifters ?

The nose on every lobe, it was a long discussion on here, the lash never changed

sounds like the lifters lived and the cam died ! billet cam? i never saw the thread... I set records with my deal .. absolutely flawless ...they are still scratching their heads wondering how I did it . always trying to learn over here !!