Its sure interesting but confusing, i can still remember hard faced cams here being built up with "stellite", i still have a couple and are hard and not a mark on them! i dont know much about whats right or wrong with the lifter subject but have allways used the cast iron lifter with the thick base and FOMOCO marked on it. An old timer that built and raced engines for 40 yrs swore by them and i followed his advice. I often wonder with lesser quality materials and good manufacturers gone that Cam break in procedure is often neglected along with incorrect oil, all helping in premature cam failure being more common. I would assume with race engines having more aggressive lift cam, higher valve spring pressures, will encourage the problem regardless. I have seen quite a few examples of premature camshaft and lifter wear of other engines, ford and C(%^&*) at my engine builders, so is not confined to our engines. Bottom line, who knows what quality anything is today! These are only my observations on the subject, best regards bill.

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

Info from Isky catalog

Isky Chilled Iron Solid lifters are compatible with our hardface overlay series cams only (not for cast billet type cams). Hardened by the chill-plate method which produces ideal surface grain structure,

Ol'ford nutCentral Iowa

56 Vic w/292 & 4 spd.

Just a SWAG - but I'd say the "hardface" was a sprayed metal technology that was applied to an "almost finished" lobe. Then it got finish ground to the specific contour and size. Wonder how thick the hardface was applied?

Don't know that the chilled lifters would be so bad on the softer cam - the scoring resistance would be good for that material too.

 
 Steve Metzger       Tucson, Arizona

Steve, Dan, and Nut:

Thanks for the replies.  This is the info Bruce at YBM has been searching for for years, and no one has clarified it for him.  I think he'll like these responses.  And Dan, I looked at an old Isky catalog, and his cams with "Hardface Overlay" required the use of chilled lifters, your memory is good.  His "hardenable iron" lifters were to be used on his non-hardfaced cams.  From these replies I conclude that chilled lifters will probably wear out a currently available cam, and if a hardface cam showed up, it would probably wear out hardenable lifters.

The link shows that there is more to lifters than hardness, the composition of the iron is crucial.  Scary, these offshore lifters. 

John - "The Hoosier Hurricane"

Here ia a site with everything you want to know about cast iron-

http://info.lu.farmingdale.edu/depts/met/met205/castiron.html

Ol'ford nutCentral Iowa

56 Vic w/292 & 4 spd.

I think I remember something about some early Isky cam & lifter kits being super hard (chilled?), and a warning about mixing them with modern iron parts?

6 VOLTS/POS. GRD. NW INDIANA

I'm a consumer of steel myself - but in my "Machinery's Handbook" (which is sort of the all everything encyclopedia of the machinists trade) it says:

"Chilled Cast Iron" - Gray Cast Iron with a hardened surface made of "White Cast Iron" - produced in a mold that has a metal "chill" for cooling the molten metal rapidly in a specific location. Compressive strength of the "chilled" surface can exceed 200,000 psi. This chilled White Cast Iron is brittle but very wear resistant - nearly all of the carbon in the hardened zone is "cementite" - in other irons it is graphite.

It looks like there are several other versions of cast iron that can be hardened (by alloy or combined carbon)- but none have spec's like the 200,000 psi listed above. It would be very resistant to scoring (surface welding) - the thing that destroys camshaft lobes.

 
 Steve Metzger       Tucson, Arizona

There has been a long time ago discussion about cast iron lifters.  Apparently there were two types, hardenable iron and chilled iron.  At that time nobody had any information about the difference.  So, I'll ask again.  Does anyone here know the difference?

John - "The Hoosier Hurricane"

Drilling the lifter bores is a controversial procedure & if done incorrectly will ruin the block. Ted has commented on doing it previously...

Paul

How many have drilled holes in the lifter boss so oil drops down to the lifter and cam from the valley? Couldn't hurt, and may keep lifter and cam from wearing.

Ol'ford nutCentral Iowa

56 Vic w/292 & 4 spd.