Contact an engine builder with lots of experience with the engine you're working on.  Don't waste your time with the cam "tech lines".  Call 5-6 of them and ask if they've ever seen an FE.  ;-)  You will find that most of the off-the-shelf FE cams are the typical 6° duration split, 110 LSA, 106 ICL.  Sure, that can work for a lot of stuff, but there are certain combinations that just need something different. 

The guys who can help the most are the ones who screw together FE's every day....and there's a handful of us on here.   So ask away. 

BTW, most of us are "custom cam grinders" in the sense that we have access to lobe catalogs from the various manufacturers and we hand-pick the lobes based on the needs/wants...then we just have a cam manufacturer grind it and away we go. 

Race T&D, no doubt.

I actually have a lot of confidence/faith in the regular rocker bodies, but once you have pulled a rocker stud out of an aluminum head, you never want to do it again.

It doesn't matter what horsepower or torque is being made

Horsepower does indeed matter and in most scenarios, it matters more than MOI.   I believe you are focused too much on distance/position and not on focused enough on acceleration. 

Tad heavy.

I had a set of JE pistons made for a 427 that used 6.800 rods and they weighed 540g.  1.460 compression height, .990" pin, .043/.043/3mm ring pack.

Inertia is a straight-line measurement... think of when you're driving in your car and you tap your brakes....your body wants to continue in the same direction it was headed. 

The moment of inertia is not really a time based unit, but it's a measurement of an objects resistance to changing rotational motion.  In physics/engineering, a moment is a tangential force which makes a torque. 

So in a rotating assembly, the crankshaft would have a moment of inertia, which would affect its ability to accelerate or decelerate quickly. 

What many people leave out when thinking of rotating assemblies and their abilities to accelerate/decelerate quickly is the amount of force acting upon them.  If you think of a figure skater, when she draws her arms and legs in close to her body, she rotates quicker.  That's what most people think of.  However, when you add a tangential force to that figure skater, you could essentially make her buzz up even with her arms and legs spread out a little. 

That's what I was referring to when I was talking about making general statements.  There are lots of variables in how quickly a rotating assembly can accelerate or decelerate.

Now, my caveat is that I'm a degreed Mechanical Engineer, but it's been 13-14 years since I've had to crack a physics/statics/dynamics book....so I'm probably a little rusty.

Watch about making generalities that only short stroke engines can rev....

I hear this statement frequently but it's not always the case.  A long stroke engine can turn some very high rpms and respond immediately with the right combination.   The rotating assembly weight as well as how much hp/tq the engine makes play a big role. 

There are mountain motor class engines (700-800 ci) with 5.750" strokes that can easily turn 8000 rpm and get there in an instant...

It is a flat . I will do everything the way I am suppossed to whats thw deal with edm lifters  is it the lifters that are weak or the cams

The EDM lifters have a oil hole on the face of the lifter.  They are pressure fed, so they continually pee oil out on the lobe. 

I also do a rain dance and chop up 3 watermelons length ways with a dull machete standing in my underwear.  It seems to help. 

Biggest thing about flat tappet break-in is to use the right oil, make sure the spring pressures aren't too wild, make sure it fires immediately, and get it up to rpm to sling oil around.  I also won't build a flat tappet engine without using EDM lifters...

I think a lot of the issue is that we are running more aggressive lobes now than we were 15-20-30 years ago and the spring pressures reflect that.  I try not to be over 100 lbs seat and 270-280 lbs open on the break-in.