Let me ask you a question...if flat tappet camshafts are so awesome, why are all modern OEM cams roller?
Flat tappet camshafts are old technology, plain and simple. However, they're cheap and I think that's an enticement.
If you want some information as to why they fail, sometimes it can be tracked down to a lifter that's not spinning, wrong break-in oil used, something blatantly obvious. Other times, there are no reasons to explain it and that's what scares a lot of builders. In the past 5 years or so, the ZDDP issue has been the topic on everyone's minds. You would think that after Brad Penn and Joe Gibbs started making their own oil that had all the necessary additives, that the problem would go away. But it hasn't...
Go hangout on the Speedtalk forum for a bit. If you're not familiar with it, it's a forum mainly for engine builders and automotive professionals. You'll read a lot of posts on there from engine builders who have been building engines for decades and are suddenly having problems. You'll also read posts on there from guys who use the right oils, use break-in springs, spin the cam with a drill motor to make sure the lifters are all spinning, etc, etc., and they will still have failures.
The bottom line is you can not guarantee a flat tappet break-in success. I don't care how old you are or how long you've been building engines. I would think that someone of your knowledge and internet prowess would have researched this a bit more.
I'm not trying to scare anyone and I'm certainly not trying to use "tactics". I'm just relaying what I know, what I see, and a lot of the talk from other engine builders. I often hear the same arguments that you're offering up, and I can see where a guy who builds one engine every several years would have that way of thinking. However, when you build a couple of month, one a week, or what have you, and you rely on it to put food on the table, then you start to back away from things that can cause a lot of trouble.
Things are slowly progressing for the automotive industry. The Cleveland is certainly not being left behind, and while some believe there are only a few ways to accomplish something with a 351, or that it's a unicorn of an engine that only a few understand, there are others that are keeping it up to date with new technology.
Next time you're around Kentucky, stop and say hi. I'd like to sit down and shoot the bull with you. I think I almost "offend" you because I'm not an old-schooler and don't prescribe to the ways that Clevelands were toyed with back in the day. However, I'm really a nice guy and a gearhead at heart.
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