[grivera]

Great YT video of numerous cams and lifters being tested on a Rockwell Hardness Tester - the short of it is hardness is not the issue with any of those in the sample:

https://youtu.be/DMFikj-TAqo

[tom s]

Mike Jones has had some posts on SpeedTalk.The way the lifter was s ground and also the way the cam lobe is ground seems to be more of a issue than hardness.Tom

[Formulajones]

This confirms what Tom is saying. Another one of Powell's videos that Grivera shared showing faulty machine work more of the cause.

https://youtu.be/MbRjAMhCEJk

[Ram Air IV Jack]

Originally Posted by tom s

Mike Jones has had some posts on SpeedTalk.The way the lifter was s ground and also the way the cam lobe is ground seems to be more of a issue than hardness.Tom

Cliff Ruggles spoke about this and said there is only one cam manufacturer in the states now and the rest are made overseas. I've heard Comp Cams are junk and that explains why they are so cheap in price. Crane was the last big USA cam manufacturer to fold years ago.

This was an interesting video, but I have a question on that hardness test. How deep or how many thousands of an inch is the surface hardness being tested? Cams at one time were casehardened and once that surface wears off, the cam begins to wear considerably. I'm guessing that the Chinese cams have less surface hardening material vs. the USA made cams which explains why so many are cheap to buy. If true, will that hardness test pick that up?

I think most of us are not surprised that the Chinese cams /lifters are not precision ground as pointed out in the video. This issue along with less zinc in the modern oils explains in part why so many cam failures are being reported with flat tappet bump sticks. IF the Chinese cams have less casehardened material, that could be any other issue. Regardless, Chinese made parts are cheap and overall, mostly inferior to what we used to see made in the USA. That is why NOS prices are through the roof now.

[racegto65]

I've been buying my cams from Clay Smith for years.
They have a pretty good supply of cores and grind all their cams in house.

[tom s]

My last 2 hyd rollers are Clay Smith.Tom

[Formulajones]

Originally Posted by tom s

My last 2 hyd rollers are Clay Smith.Tom

Are you doing a Clay Smith stick with the new Comp 2 piece hydraulic rollers??

[BILL BOWMAN1]

I’m going to stick with roller stuff until this is cleared up.

[Formulajones]

I'm more of a roller guy anyway and have been for decades. I only run the flat tappet stuff in particular situations.

[tom s]

The engine on my run stand has the Shavers,the round port I’m building next will have the cartridge lifters.Have not bought them yet.It’s nice being able to drive to CS cams and talk to I think George.Tyree used his cams for years.Tom

[turbo69bird]

Anything good enough for Jess T is good enough for me. Good info. I’ve always bought my cams from cam motion or ultradyne at one time also. Always had good stuff but can’t say recently because it’s been a while .

[NeighborsComplaint]

Originally Posted by Formulajones

This confirms what Tom is saying. Another one of Powell's videos that Grivera shared showing faulty machine work more of the cause.

https://youtu.be/MbRjAMhCEJk

The face of that lifter was ground with less precision than I grind a buggered up screwdriver blade. Unbelieveable, You could literally see how "cupped" they were from sloppy machining.

For you quys who may not have been around on the good old days when OEM lifters were available, they were micropolished and the corner the video spoke about was sharp with no excessive radius.

[Jack Gifford]

Originally Posted by Ram Air IV Jack

... there is only one cam manufacturer in the states now and the rest are made overseas...

I'm not sure if that's true. I recently had Comp Cams regrind some damaged lobes for my lakester's DOHC hemi four (I used Comp Cams only because Robert Freund, who designed my billet cams while at Crane, is now at Comp). It seems unlikely they would ship the cams oversees to have some lobes reground, no? I could try asking Robert.

[Formulajones]

I think it was mentioned Clay Smith grinds all their own stuff and if I remember correctly Comp does stuff for Lunati and a few others, some of which they own.
Would be best when a video is made like that stating faulty machine work that they just come out and say where that was done to maybe cut down on confusion. He doesn't say anything about the lifters in the video being Chinese and shows a crower box in the background. Never comes out and says they are Crower either. Are we supposed to assume they are Crower? Assuming may start false rumors.
Also begs the question, who machines for Crower if those are in fact Crower lifters??

[Jay S]

There are tons of small cam mfg here in the states, there is certainly more than one big company left. CMC grind’s a ton of cams here in the US. To my knowledge Crower is all in house. During busy season’s Bullet runs 3 shifts almost around the clock. Compcams grinds a bunch of cams at their complex in the Memphis area, including Lunati’s, and also subs out a lot of cam grinding to some of the smaller cam companies. Likely some are overseas, but most are not. I know Cam Motion in the past has ground a lot of modern HR cams for Comp.

I thought those were both good videos with a lot of good info. Pretty sure he was inferring the lifters came from the packages next to where he was testing them, they were Crower’s. All I know is Crower does not use Hylift Johnson anymore for flat tappet lifters, and if they are, Crower labels them as Johnson. That was some ugly machining on those lifters. It also begs the question, if they are that bad on the outside, how good is the machining on the inside?

He tested a variety of cams and lifters on that video. Mostly what I thought it showed was there are very often more reasons for a cam loosing a lobe than soft metal. One cam he tested that failed had no taper on the lobes, and the owner had 3 cams in a row fail from the same Mfg. He mentioned one cam had too much tapper. At least one cam on the video was a P55 core, which is a tougher core than a typical flat tappet street cam. Several of the lifters had a hardened foot, you generally expect them to have a higher hardness. Upper 40s to lower 50s on Hardness is very common on lifters, pretty much exactly what his video was showing. Lower 30s is common on most flat tappet cam cores, some can drop into the upper 20s. None of his testing showed anything that low, but it appeared to me several of the cams he was testing in the video were better cam cores than standard proferral cores. What his cam hardness video clearly showed was if the parts are not machined correct the higher hardness will not help.

[Formulajones]

So anyone here want to be a test mule with out of the box Crower flat tappet cam and lifters to see what happens??

[Jay S]

Originally Posted by Formulajones

So anyone here want to be a test mule with out of the box Crower flat tappet cam and lifters to see what happens??

No kidding, it is kind of scarry!

There was just a thread on here talking about it took 3 sets of Crower’s to get one good set on the face machining.

I helped a friend putting a 389 together earlier this summer and suggested Crower lifters as best of the cheap lifters, at the time HLJ were impossible to find. My friend that runs a machine shop is putting it together, better look them over good!

[Formulajones]

I've never used anything from Crower before.

I do use the HLJ lifters on the hydraulic flat tappet stuff when I can find them but I honestly don't do a lot of flat tappet cams. I mainly stick to rollers and even then I'm picky about the rollers I use.

My flat tappet cam stuff has stuck with Comp primarily, and some Crane back before they shut down so that's been a long while. I've never had an issue with them.

Probably the oldest setup that still works fine is the Nomad that has a very old solid flat tappet grind in it and I'm trying to remember if it's a Clay Smith or Isky. That's been together since 1972-ish lol.

[Stan Weiss]

There is a limited number of places that make flat tappet cam cores. Most of the cam companies get their flat tappet cam core from the same place. Now the question is what does your cam company with the flat tappet cam core?

Along the same lines is that many companies also buy for a better term white box cams which are already ground and ready to sell.

Also the radius on the bottom of the lifter needs to be matched to the tappet ground on the lobe.

Stan

[tom s]

Guys,Mike Jones posts quite a bit about flat tappet cam on SpeedTalk.He grinds a lot of FTCs with diff material cores and lifters.You have to pay attention and read pretty much every FTC thread to pick up some things.He usually try’s to hold back proprietary info.Many threads over there.FWIW,Tom