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Old 10-01-2006, 09:16 PM
Excaliber Excaliber is offline
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Good point about the buying the heads AND matching cam\lifters 'kit' so you don't have to 'mess with anything'! I concur, custom pistons are a HUGE expense, with care the hypers should work fine. 292S cam may flow more air than those heads will allow for, a milder grind may be warranted.

The lifter turning in the bore is the KEY, man did I worry about that. Don't care what kind of oil you got, if it don't turn, your screwed. It seems reasonable to me that with less spring pressure pushing the lifter onto the cam lobe you increase the likelyhood the lifter WILL turn. I DO think the individual cam lobe and lifter bottom 'wear in' to match each other, that takes about 20 minutes, and it either happens or it don't.

It's ALWAYS been standard operating procedure to match used lifters on the same cam lobe they came from if your remove lifters or cam for some reason. So, nothing new there.

And wiped cam lobes\lifters have always happened to some engines, at some point, nothing new there either. Whats different is the much larger number of cam\lifter failures we have seen in recent years. Cam manufacuters attribute this to the new oil formulations, I tend to agree. In addition I suspect 'we' are also seeing higher spring pressures than were common 'back in the day'. Thus, a double whammy effect, more pressure, bad oil, deadly combo.

Whats REALLY disturbing is another question you touched on. AFTER breakin, are we STILL subject to loosing a cam prematurely due to the missing additives in the oil? Maybe! Especially considering that many of us don't drive our replicas 'daily', indeed they may sit for weeks or even months at a time. While the oil slowly drops away and returns to the pan. On startup, your recreating the fundamental problem you have with a new motor, limited or no oil on critical components. You are now COUNTING on that breakin period for the cam lobe and lifter to work together with minimum lubrication.

Which is exactly WHY I'm dumping synthetic oil and going back to Shell Rotella for Diesels. Which DOES have more of the missing ingredients than other oils curenntly on the market! Paranoia or science? I don't know, my gut tells me, go with Rotella.

BIG QUESTION:
So the motor has been sitting for weeks or months (like all winter). The lobes and lifters are mainly oiled by 'splash', thats why you hold the rpm up around 2000 and vary it when breaking in a new cam for the first time. The question is: When starting a motor thats been sitting a long while, do you bring it right up to 2000 or better to 'splash' the cam\lifters again? Or do you let it idle at a low rpm until the oil starts to flow and gets around the internals before your 'rev it up'? The question itself makes a case for ultra light weight oil to begin with, 5-40 or something of that nature.

Last edited by Excaliber; 10-01-2006 at 09:21 PM..
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