[jonmachota78]

Butt its been a great engine for 16 years and over 40k miles. Built in 2008 with the 274ex flat hyd and upgraded to hyd roller OF cam in 2012. Plenty of dragstrip runs, i can't complain.

It started making an unfamiliar noise, valve train frequency except not a hammering like a colapsed lifter, rather a scuffing/sqweeky noise. Removed the belts and looked for vacuum leaks to no avail. Put a tube in my ear and couldn't pin it down to one side or the other so figured its time to look at the cam. I kinda felt i was on borrowed time.

Jon

[Half-Inch Stud]

Geez. As if Flat HYD is equally reliable at lower parts cost.

If engine builds were a MIL-Spec'd situation on Parts ratings and de-rated use in operation, i wonder what the Can durations, lifts and spring Seat Pressure and Max open Pressures would be. For Flat HYD, Flat Solids, and Roller cam versions.

You know, for 15-year life of daily use. Oh, 10 year and 5-year. Just to see quantitatively, which parameters ratchet down for long life.

[PAUL K]

Bummer!

[tom s]

Looks like the bearings went away?Tom

[NeighborsComplaint]

You should open a cam grinding business ... your "design" eliminates the link plates, lifter roller stays in the groove and the round lobes are easy on the rest of the valvetrain!

[jonmachota78]

Originally Posted by tom s

Looks like the bearings went away?Tom

I haven't inspected the rollers yet. Ill be sure to post pix

[jonmachota78]

Could this OF cam be reground down to a Stump Puller?

[78w72]

Which brand/version are the lifters?

[Steve C.]

Could this OF cam be reground down to a Stump Puller?

Possibly.

I had Bullet regrind a damaged solid roller years ago.
At the time it was $157.50 plus freight.

Example.....

"Should not be any issue, if the cam was made correctly to begin with.
We check the part# of the core to find out what the lobes were roughed to before it was heat treated, then we measure the current lobes to see how much material was taken off, and how much heat treat is left for regrinding."

https://www.yellowbullet.com/threads...-a-cam.483571/

.

[jonmachota78]

Originally Posted by 78w72

Which brand/version are the lifters?

Comp 857's from around 2012. Im thinking they are Morels?

[jonmachota78]

Originally Posted by Steve C.

Could this OF cam be reground down to a Stump Puller?

Possibly.

I had Bullet regrind a damaged solid roller years ago.
At the time it was $157.50 plus freight.

Example.....

"Should not be any issue, if the cam was made correctly to begin with.
We check the part# of the core to find out what the lobes were roughed to before it was heat treated, then we measure the current lobes to see how much material was taken off, and how much heat treat is left for regrinding."

https://www.yellowbullet.com/threads...-a-cam.483571/

.

Interesting. Especially if someone wanted to buy it 😁

[tom s]

I think back then they were using Morels as a sub lifter.For sure they are not the Shavers.Tom

[Dragncar]

Originally Posted by jonmachota78

Could this OF cam be reground down to a Stump Puller?

You have about .030 to play with and you might be able to re grind it to the original cam.

[tom s]

As I recall back then Johnson was supplying Comp their hyd roller lifter.After they went with Shavers and subbed Morels when out.Those could have been Johnsons.Tom

[Formulajones]

Does appear to be a bearing issue and wheel skipping or locked.

Like Tom said hard to nail down a brand as comp had 3 suppliers. I don't remember what year the 857 "S" lifters showed up as well. I think that was a little later.

May be more identifiable when you pull them out and snap a pic

[grivera]

Damn - that sucks! Sorry this happened.

[jonmachota78]

Thanks for the input all, ill try to get you some pix tonight.
Its was running 1.65 HS rockers and remember measuring. 660" lift on the exhaust when i measured for push rods. Im not sure if running that much lift on a street car is a contributing factor to the failure

[Formulajones]

I doubt it plays much of a roll only because we've run that much in street engines for many years, mine being together for 25 years for example, without issue.
I'm running the Johnson lifters.

Hard to say, a lot of factors play into these issues. Open pressures at those lifts would be interesting to compare though.

[jonmachota78]

Bearings didn't leave. They don't feel real bad honestly. Not quite as smooth as the other side butt.... Im not sure why if it quit rolling and started skidding. No flat spots but you can see fatigue pitting and it spins freely

[jonmachota78]

Pix