Hydraulic cam core Used for a.roller regrind?

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1969GTS340

1969GTS340

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As the heading / question suggests. Can a flat tappet hydrualic cam from an LA be used as a core to make a 360 magnum roller.cam?

Aside of actual lift, duration, etc... details. I'm curious if the flat tappet lob shape can be reground for a roller lifter?
 
1969GTS340 said:
As the heading / question suggests. Can a flat tappet hydrualic cam from an LA be used as a core to make a 360 magnum roller.cam?

Aside of actual lift, duration, etc... details. I'm curious if the flat tappet lob shape can be reground for a roller lifter?
Click to expand...
I'd be more concerned if the metal was good enough in the hydraulic cam to be used.
 
1969GTS340 said:
As the heading / question suggests. Can a flat tappet hydrualic cam from an LA be used as a core to make a 360 magnum roller.cam?

Aside of actual lift, duration, etc... details. I'm curious if the flat tappet lob shape can be reground for a roller lifter?
Click to expand...
That would be a no. There would be no material left/available to accomplish this. A few comparisons. Flat, next a roller. FWI. that roller was overkill.


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thing is, a flat tappet cam has lobes offset from lifter bores, roller cam has lobes in line with lifter bores, not same cores.
 
I've talked to Ken Heard about this very thing in depth for a slant 6 cam. He said as far as the physical aspects of actually grinding it, he can do it. Whether or not it'll hold up is another story. He's done a few for some of the guys on the slant 6 .org site and so far, they're running good. He said he thought that as long as you kept valve spring pressure moderately low, you'd be ok. He didn't recommend any more than about .550 or so lift. But he said he could do it and has before. So there's that.
 
I’ve asked Ken about it with the SBM before. He says the small block hydraulic lobe centers under the lifter and the flat tappet is offset under the lifter bore. The metal is okay, but only half the roller runs on the cam on a flat tappet ground for an hydraulic roller. He says there’s one of the major reman engine parts company that had been doing it, and failure rate was near 100%. So yes, find a hydraulic roller core.
 
1969GTS340 said:
As the heading / question suggests. Can a flat tappet hydrualic cam from an LA be used as a core to make a 360 magnum roller.cam?

Aside of actual lift, duration, etc... details. I'm curious if the flat tappet lob shape can be reground for a roller lifter?
Click to expand...
Stock used Magnum cams are plentiful. That is the best way to do a regrind, as long as you not looking for something “really big.”
What kind of application are you looking for intended use?
 
Call Oregon Cam Grinders and ask them. You really need extra meat in the lobe if you're going to take true advantage of running a roller cam.

That fat lobe is all extra time that the valve is being held open.

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as i stated, this was told to me by ken heard at oregon cam, just passed on what i was told,
 
Lunati ground a roller cam for me from a new LA core for a Magnum 300hp crate motor. New cam on left, stock crate cam on the right.

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Bobzilla said:
Stock used Magnum cams are plentiful. That is the best way to do a regrind, as long as you not looking for something “really big.”
What kind of application are you looking for intended use?
Click to expand...
I am considering to build this 360 magnum as a short block / back up to my current 340 race motor, in the event that I needed it. A lift in the area of .600 for starts and probably change pistons as well to get the Magnum in the same 450ish HP area.
The 340 has early EQ Magnum heads ported and magnum RPM AirGap. This is more of a back burner build but I'm doing some homework to see what I would need.
 
1969GTS340 said:
I am considering to build this 360 magnum as a short block / back up to my current 340 race motor, in the event that I needed it. A lift in the area of .600 for starts and probably change pistons as well to get the Magnum in the same 450ish HP area.
The 340 has early EQ Magnum heads ported and magnum RPM AirGap. This is more of a back burner build but I'm doing some homework to see what I would need.
Click to expand...
I see. Yup, not getting that much out of a Magnum regrind, I don’t think.
 
1969GTS340 said:
As the heading / question suggests. Can a flat tappet hydrualic cam from an LA be used as a core to make a 360 magnum roller.cam?

Aside of actual lift, duration, etc... details. I'm curious if the flat tappet lob shape can be reground for a roller lifter?
Click to expand...
No. A roller regrind has to be on a roller core. Period.
 
What is the cost of doing a regrind compared to buying a new cam? Just curious as i would queation is there much of a value to risk reward?
Rod
 
1969GTS340 said:
As the heading / question suggests. Can a flat tappet hydrualic cam from an LA be used as a core to make a 360 magnum roller.cam?

Aside of actual lift, duration, etc... details. I'm curious if the flat tappet lob shape can be reground for a roller lifter?
Click to expand...
Because of the contact area between the cam lobe and the lifter functions differently, there is no material where you need it to grind the roller profile.
On top of that the cam core chemistry or metalurg is different. That is why most roller retro fits need the distributor gear replaced. Some build a core with the roller metalurgy but put an iron distributor drive gear and end bearing on the core. This works for Chevys and rear distributor Mopars. BBM and Fords do not lend themselves well to this.
 
rod7515 said:
What is the cost of doing a regrind compared to buying a new cam? Just curious as i would queation is there much of a value to risk reward?
Rod
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I think my roller regrind was $180 including shipping. Good price for a roller cam IMO. Started out as a roller core. I used Oregon. Plus I was able to reuse my magnum lifters after inspection and cleaning. My pushrods measured out ok too. All good with about 1200 miles on it.
 
rod7515 said:
What is the cost of doing a regrind compared to buying a new cam? Just curious as i would queation is there much of a value to risk reward?
Rod
Click to expand...


I believe the real issue is finding a blank cam core to grind one...

The small blocks are long out of production and who is going to make a raw cam core for an obsolete engine??? Not enough volume/profit to make it worth while...
 
krazykuda said:
I believe the real issue is finding a blank cam core to grind one...

The small blocks are long out of production and who is going to make a raw cam core for an obsolete engine??? Not enough volume/profit to make it worth while...
Click to expand...
There are still scads of "obsolete" engines running out there and being rebuilt and hopped up. Cams are available for stovebolt Chev 6's, A, B and C Ford bangers, Flathead Ford V8s, Ford 6s and the slant 6. A little tougher to find a cam for say a GMC 376 CID V6 or 351M.
 
Call Delta cams. The last time I talked to him, which wasn't long ago, he said they had no trouble coming up with cores, that they had a huge inventory.
 
rod7515 said:
What is the cost of doing a regrind compared to buying a new cam? Just curious as i would queation is there much of a value to risk reward?
Rod
Click to expand...
When I damaged my solid roller (too short pushrod, broke an adjuster, chucked one lifter out, other went sideways), I had it reground. I lost quite a bit of lift, added unwanted duration, but it cost about a quarter of what a new billet roller would have cost, and still ran quite well. They did the best they could with the damaged lobe, so I have no complaints.
Cost for a regrind will depend on if you have a core or not, whether cores are fairly common, what kind of grind you want, and who is doing it.
What's nice about rollers, you can change cams and re-use the lifters (if they are still in good shape) something you can't do with a flat tappet.
 
When the new cam dynamics roller I intended to use in my small block chevy wouldn't fit (rods hit the cam lobe), I bought a small base circle regrind roller from Americam, ran very well, was about half of a new custom roller. Ita cast core, not a billet, and I used new lifters.
I have no idea if Americam is still in business. (Southern California).
A roller regrind kinda automatically makes it a small base circle cam.
Edit: I got the name wrong, it's American Custom cam. They saved my maxwedge billet roller, and supplied my small base circle small Chevy roller. I'm probably gonna get a roller from Joe for my new Opel engine.
 
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