For a BB Mopar?

Cast cores used with roller lifters are made of a different material than what is used with flat faced tappets.

AFAIK, there are no SADI cores(ductile iron, the material used for roller lifters) made to fit BB Mopars.

I wouldn't personally run a 5150 core with those specs.

You would have better reliability out of an 8620 core but of course need to make sure spring pressure and everything else in the valvetrain is correct.

JMO

Yes, his was a steel billet but likely (99.99%) it was as Fast said 5150 base. I vaguely remember him saying that Comp would offer him no $break$ for a replacement and they did say that the 8620 SHOULD have been HIS request for his application AND would be a $ upcharge verses the 5150 cores.

Here's mine after 10 years on the street with Mobile 1 Yes it is a copper core.

I haven’t had any problems with the 5150 cores.
That’s what most of the BB Mopar cores are these days.
They simply don’t always have 8620 cores that are suitable for every combination.
And if they do, they’re usually more $$$.

Unless Marks cam looks way worse in person than in the pics...... I still say it looks pretty normal to me.

Is BES ok with reusing that cam? Maybe now is the time to let him spec your new one ?

I'm DOOOOOOOOOOOOOOOOOOOOOOOOOOOOMED!!! I have a BLACK CORE CAM!!!

( Hee hee! )

Years ago, early to mid 1970s, I had two Isky solid rollers that I'm sure where cast core camshafts also
None bought since from any other company

NOOOOOOOOOOOOOOOOOOOOOOOO,, dont take it apart & start over

The cam is being replaced. New one is on its way. That was always the plan.

If it's still straight and otherwise in good shape, might be a nice one to regrind, if there's
enough meat there in the right places to create a different profile.

Looked at it some more tonight.

It’s the worst on the opening side. At max lift not too bad and gets worse on the closing side but not as bad as the opening side. Base has no marks.

The worst groove is 0.0008 inches - so almost a thousandths. I actually thought it would be worse.

The worst ones have pretty significant burrs.

Have you compared the width of the contact portion of the roller wheel versus the edges of the contact patch on the lobe?

I have not but it looks to be pretty much the width of the roller.

Some additional pictures showing the damage better.

it looks like one side of that lifter is hitting the cam lobe before the other side, it looks like it is loosing contact with the lobe after max lift
I would replace (or have them rebuilt with new wheels, axles and bearings) all the lifters off of the lobes that look like that

Somewhat from out of left field...
- Rocker brand & ratio?
- Pushrod length, diameter & wall thickness?
- Did you find the spring specs and any info on how they were installed?

Speaking strictly as an amateur bystander, I'm wondering if the opening & closing flanks are showing the result of insufficient valve train control, or a lubrication issue.

Still looks totally normal to me.
The more pics I see the more normal it looks.

All 16 lobes on the cam I posted the pic of have the same impressions on the opening side, in the area where the big change in velocity and pressure angle occurs.

Anyone got a pic of a typical drag race roller cam, that’s been run with typical drag race spring pressures for 100 or more passes that doesn’t have those marks on the opening side?
Let’s see some pics and specs.

.0008
Give me a break. 😂
Lmao

I have a Bullet cam that looks just like that. And it eat a lifter and screwed it up....I could take some pictures and you wouldn't be able tell them from yours. When I first switched from a solid to a roller in my big block it was even worse. We sent the cam back to Bullet and they checked the hardness and it was ok, reground it, I put it back in and it did it again. I ended up upping the spring pressure and it helped, but I don't think I ever totally eliminated it. Since then I have been through several different lifter styles, cams and even blocks and it has always done it to some extent. I have to pull the engine and go through it here shortly and its got a few hundred passes on it and I bet there is some evidence of it still doing it.

I would like to know what the issue is if anyone ever figures it out. I have a theory that it might be related to the roller diameter, lobe profile and the geometry of the lifter bores, but that is just a guess.