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If you're depending on zinc to protect your flat tappet?

I'm going to stick with my opinion that a good portion of the FT problem is ramp speed and spring pressures. I think when Dave Hugh's started this 904 lifter profile thing it just went extremes. I stay away from it. Reliable use of my cars is paramount. I'll gladly give up some power for reliability. I have an Engle k65 solid in one me 440's and it's been in there for over 20yrs, about 23,000 miles on it. It's not a fast lobe, may go away tomorrow but I've had a good run on it.I don't use high rate springs, and mostly Rotella oil. I'm not saying use Rotella because there are other good oils, I'm saying don't depend on oil to save your butt because you made a poor camshaft choice.
I'm not very familiar with cam profiles and ramp speed, but I can certainly see where metallurgy plays a part in cam survival. I had a Crane ductile rockers set go bad because the tips were wearing. I wouldn't trust them for cams after that. I'm currently running a Hughes STL3842 solid lifter cam in my GTX and haven't had an issue. I broke it in to their specs using their break in oil and lube. Running good oil is just upkeep.

I do say! Back in the day Kendall was the only oil that would quiten up a noisy primary chain on several 750 Hondas that I owned. Also my FIL had a 500 CX with noisy valves from the factory. They were adjusted correctly but noisy. Used Kendall and the noise was gone.

Another example was my FIL was changing oil in my wife's car. He used Quaker State and the foam and gunk under the valve cover was unreal. I changed the oil and filter and used Kendall. Two weeks later the sludge and foam was gone. My life's experience with different oils, Kendall comes out on top.

Nice to know you can get it up there. Summit?
I think there are several factors present on cam failures. For the most part, if you loose one lifter or two, either right after break in, or after several thousand miles, but after the failure, the rest of the cam looks good, that is either soft metal or improper machining on those lobes that failed, and the problem probably can be traced back to the break in. If the machining was poor or the metal was soft too much metals gets removed during break in, aggressive profile becomes even more of a problem, and a bunch of taper gets removed breaking in the cam, and it shortens the life of the cam, if those things are bad enough it won’t even last past the break in. It could have barely broken in also, and 10,000 miles later the same thing happens because the oil wasn’t doing it job either. The slow death…

If the cam breaks in ok, but it looses a lobe a few thousand miles later, but on inspection, the rest of the cam lobes look like ****, that likely a lubrication problem. Could be not enough taper on the cam too, but not likely, better chance of being an issue with lubrication. Most people don’t drive there cars enough anymore to find out there oil sucks. They just get the cam broken in and think everything is good. Lol
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