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Can cams be had for Packard's 245 CID sixes??? Or is one stuck trying to find NOS of good used?? Does anybody know if they are Packard specific or can they be interchanged with other engines???

Doubt any other engine would swap since Packard pretty much made things like that in house. Unless you luck out on ebay doubt if any will be too plentiful from an aftermarket supply. Kanter lists rebuilts available either with an exchange or with a core deposit refundable when your old rebuildable cam is returned. Would assume anything labeled as rebuilt have been checked out thoroughly or reground to spec. You might try flackmaster and see if he might have latched onto some old stock.

I've always wondered how "re-ground" cams would be effective...reducing lift and duration I would think the opposite of what would be necessary to return to stock, or better, performance..??

And a for a NOS cam. Boy, you've really twisted my brain on that. I know I had one, and I can usually put my hands on my stuff blindfolded, but you really have me thinking now...where is it??? Gosh, may have to take my feet off my desk and get out of my chair...

Yes, confirmed. Just where its been for, umm....a while. NOS in Packard wrapping.

I wondered about reground too and how they would maintain lift spec. In an episode of "How It's Made" they showed cams being done at a rebuilding facility. If they are all treated like those on the show, the old cams were ground down slightly more to prepare the surface and then had metal added back via an automated welding or another process. They were then placed in a machine and the excess reground off. They then had some kind of metal re-strengthening and finishing. The announcer said the cams were either returned to factory spec or could be modified to different specs depending on the desired use.

Thanks Howard and David. I too was curious re the 're-ground route'. I know from my working days that they have developed some pretty impressive chromium steel alloys today that are super hard and abrasion resistant. Guess it boils down to the 'job you get', and how good the regrind place is at resurfacing. The machine shop that I am using to rebuild my motor thinks the cam being worn 'past spec' is almost a given and they are asking me about availability should one be required. They tell me that the old one can be redone but an aftermarket reproduction or a NOS would be better, so I think that kind of 'tells the story'.

See Cams Northeast or Oregon Camshaft Grinding

Quote:

As long as it's ground properly and to specification, the lift would be identical to the original as it's based on the round side to the top of the lobe. If only the lobe is ground then you're right, the lift would be off but typically the entire surface is ground by the same amount to maintain the lift.

'As long as it's ground properly and to specification, the lift would be identical to the original as it's based on the round side to the top of the lobe. If only the lobe is ground then you're right, the lift would be off but typically the entire surface is ground by the same amount to maintain the lift.'

I have to say I am confused by this description of cam grinding. The tip of the lobe is what wears and instead of being elliptical, the lobe becomes more or less round. the ONLY way to restore original lift is to replace the lost material and regrind to spec. Reducing the round part of the lobe and grinding 'the entire surface by the same amount' to recover the lifting motion of the cam, will definitely make the valve open and close again, but it would be impossible for it to achieve the original lift spec, or the total amount the valve is opened. Am I right, or is there something I'm not understanding???

Not quite true as it's back to the lift. From the centerline of the shaft measured to the round side added to the centerline of the shaft to the lobe side will remain the same if ground to spec. Obviously the valve lifters would need to be adjusted because the cam is a bit farther away but the lift will remain the same from the low side to the tip of the lobe. If the tip were the only thing being ground then definitely the lift would change but not if the round part is also ground. The radius on the lobe is also important as it detemines how quickly the valve opens and closes again.

Thanks Don, interesting... not sure I am able to get my head wrapped around that, but I suppose if the lifter can be adjusted to make up the difference, I guess I can see it....
Again, I imagine it depends on how badly the cam is worn - if only slightly, I think it would be okay. Anyway, thanks for the explanation....