Whats up with flat lobes on new cams?

[dwg86]

I hear alot about this happening, and although it has been a few years since I have built an amc engine, a 304 and 401. But what is going on with the newer cams? Also it seams this is not only an amc problem.
I didn't have any problems with the cams I used(and like I said its been a few years). I used a comp cams 280h in the 304 and a custom ground REED cam in the 401(intake 228 dur @ .050/.512 lift, Exhaust 232 @ .050/.518 lift 110 center). Break in on both cams 2000 to 2500 rpm for 30 mins. I couldn't run for the whole 30 mins at one time due to eng getting hot.(due to timing and carb misadjustment on initial break in). I don't try to fine tune anything until the cam is broke in.
I like to use an electric fuel pump so gas is ready as soon as the eng turns over. My Dad showed me a trick years ago for timing an eng to get it close enough to run for cam break in, and it works pretty good. Put the #1 cylinder on the timing mark on the balancer(i.e. 10 btdc) on the compression stroke. With the rotor pointing close to the #1 position on the cap take the coil wire off the center of the dist. and hold it close to a good ground with the other end still connected to the coil. Turn the distributor until you see a spark. Lock down the distributor, because thats when #1 will fire. Gas/spark ready to go.As soon as it starts...go to 2000-2500 rpm.
I am getting parts together to build a 4.0 stroker for my 2003 Wrangler (258 crank/rods in a 4.0 block). Flattening lobes seams to be a problem some people are having when they build the 4.0 also. What gives?

[CJim7]

It's that damn out-sourceing. I think there's a lot of inferior steel being used nowadays.

....And that is my uneducated guess.

[Goose]

Well thats as good a guess as any. I find it hard to believe that cam break in could have that much to do with a lobe going flat in 30 miles. I would buy that improper break in would shorten the expected life considerably.. but not to 30 miles.. The other side of the equation is spring pressure or pushrod length.. When you start decking engines, milling heads and altering geometery of the valve train ..you don't have to a super guru.. you do have to double and triple check EVERYTHING.. And that is just the price of going fast.

When you combine the above with poor quality control in mfg plants and cheap materials.. sooner or later your gonna get bit.