OK, Timing: we have gone through the gambit of rotating the distributor and have found the "sweet spot" where it runs and idles OK. It is not a stock grind, a little more lift and duration went into it from a very reputable shop, not super aggressive. We put in longer pushrods to accommodate the cam. We're pretty sure the issue is here but are still working on it.  Timing marks on the damper may be an issue with the new cam but our issue is bad compression numbers on all cylinders and hard starting.   It's got to be in the valves.  We did our own seating and grinding so we might end up swallowing our pride and taking them to a real shop for verification of our work. We could also end up going back to the stock grind, I have an extra cam. Funny, once we get this thing dialed in we're gonna take the top off and set up our webers and then back to the drawing board with linkage and fuel lines.. Trying to find a generic throttle linkage kit for the four twin stack webers has been impossible. 
RB: hydraulic lifters, vacuum checks out at 20-21 with just a very little flutter.

I got an engine to run once being a tooth off and it was unbelievably bad. Back when it first started building performance engines I had to get a wider key and machine the sides to get an advance or retard; there were no notched crank gears or buttons for cams. and it was a pain. Thanks to my dads mill and his advice i was able to do it; then remember with no chain put it in backwards. I also does not sound right that a cam grinder would grind that much into any cam and only on a new casting or billet. Interesting reading and suggestions for sure... 

56 Vic, B'Ville 200 MPH Club Member, So Cal.

One tooth of timing is way too much either way.. My guess is it one tooth off retarded.  Make sure the timing marks are lined up so your cam is in the straight up position.. There are no adjustable cam components for these engines..  Is the cam reground stock? 
If your  timing marks on the damper are off due to the damper ring slipping, you will get an erroneous ignition timing reading. Try advancing the distributor while it is running.  If the engine smooths out, give the engine what it wants not what the timing marks say. One more thing to check  You may have a big vacuum leak somewhere which would make it hard to start and run hot due to lean fuel mixture.
 Do you have hydraulic or solid lifters?  If hydraulic, the rocker arm adjuster screws may have too much pre-load on the lifter and it is not letting the valves fully seat.. Just another item to check..

Thanks for all the advice.  We are checking each and every idea. Gas is not an issue. Timing is our first thought, that's what is going on now. We had the timing marks spot on but maybe we needed to advance/retard one tooth because of the new cam grind. If the cam is more aggressive, should we advance the mark one tooth or retard?  It's just me asking, Jeff probably already knows.

Check the balancer for true top dead center.. Like Joe says, hard starting and hot exhaust says retarded ignition timing... Low cranking compression, if I had to guess, you are one tooth off on the timing marks and your intake valve is closing late..Was valve to block/piston clearance checked?  Lincolns are particularly bad on the intake side . The valve hits the block with lift over .500 and it does not take much to tweak the valve head and lose some seal   Do you have the specs on the cam you installed?  If none of these things are at fault, sadly, the problem is much deeper

Definitely get a leak down tester.. it will tell you if the compression is escaping through intake or exhaust valve or getting past the rings

Was fresh fuel being used when the engine was first started?  If the gasoline was over 90 days old, it is suspect.

Lorena, Texas (South of Waco)

Typically, retarded timing will cause the engine to run hotter than normal, and if it is getting worse, I would pull the distributor and look at the gear, and the pin holding the gear on the shaft.  Next, would double check the camshaft install with degree wheel to make sure it is correct.  Joe-JDC

JDC

We can't figure it out. It started up right away first time. After it got hot we shut it down fearing our temp gauge might be faulty. Tried to start it again and nothing. Messed with timing for a couple of hours and gave up.  We went back yesterday and it was worse than before. Finally got it running but didn't like it. Did a compression check last night and every one of them is under 100.  We did put in a hotter cam so we're going back to the drawing board and re-checking valve timing.  Maybe we need to add/subtract a tooth.

Does it still have the carb and stock manifold? What changed from 4 days ago when you said it was running with no mention of a hard start. Was the 4 days ago start a typical one with a run to 2000 rpm and hold 20 minutes with a total timing check? Just asking..

56 Vic, B'Ville 200 MPH Club Member, So Cal.

ALL cylinders have low compression.  We're thinking the cam timing is off.  With the change of cams to something a little hotter, we didn't change the dial in stock setting..We're going to investigate to see if we need to change that. If it improves the compression, we have found our gremlin. This is the second engine Jeff and I have built together, I don't think it is a builder problem.  He's too anal. Thanks for getting back to me.