Here's an interesting one I thought might benefit someone someday. I was gonna do a "where's waldo" deal on this one too, but I think it's best not to.
Terry (HDRiderth) was helping his buddy Jay get his boat set up and running after Jay and his buddies put a new cam in his motor. After setting up the valve lash, trying to break in the cam the thing clattered like an old Model T I guess, but ran even and idled I guess on Friday night. So Saturday we all went floating, Jay came along with me during our version of the "Deadliest Catch"....a story unto itself, then Sunday we went after the motor again. Backed off all the roller rockers, Terry was turning the motor over as I set the valves. Had only set #1 and Terry felt resistance. I pulled the rocker and found the intake pushrod bent. pulled them all, and every intake pushrod bent. Some substantially
Terry thinks cam is too big and coil bind or retainers bottoming out on the guides and seals, or rocker slots hitting the studs. But we put in a stock pushrod, nope, plenty of clearance. So we start thinking cam timing, was in my mind the whole time, but I kept rationalizing, normally if cam timing it's the exhaust valves that have the issue, and no way it'd run. So off came the balancer and timing cover.
Anyone not real familiar with multi-keyway roller timing sets, a Comp Cams unit in this case, need to note that there are three marks on the keyways, and three corresponding marks on the outer edge of the timing set that are to be set up to point to the dot on the cam gear. Pretty easy mistake to assume the keyway and mark on the keyway lined up with the dot on the cam gear it's dead on timing. Seen it happen years ago, but not recently. The marks on the teeth on the outer edge in this case were VERY faint, but were none the less present.
The only reason for multi keyways is to be able to advance or retard cam timing +/- 3 to 4 degrees. Dont even think about it without a degree wheel, and should be done when the engine is in short block form and again when the heads and valvetrain are installed as a double verification. Normally not necessary these days, but there are times, mismatch in components, valvetrain geometry, tolerances out on parts, etc where it can come in real handy. Otherwise, just use straight up timing. But, if you use the "O" keyway, the actual timing mark is the corresponding "O" on the outer edge of the crank gear! same with the other marks.
This particular case, the cam timing was out a whopping 45 degress and the engine ran!
He dodged a very big bullet, no apparent piston, cam, valve or head damage (Thank god he bought "el-cheapo" hardened pushrods and it was a hydraulic cam and the lifters had not even gotten pumped up. We picked up an oil priming tool this time and ran it a good half hour before we got oil through all 16 pushrods). We replaced the pushrods with good chrome moly's, boat ran like a top all day Monday!
Valves need readjusting probably now that it's broke in, and another compression and leak down test to make sure all is well.
Just some FYI for us backyard mechanics!
Ray
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But I'm looking for a 12 7/8" on center scoop for one of my Kuhl setups. Yes there is a plan for it, and yes, it's gonna hafta wait for disclosure like the rest of my $hit. 
