I thought I would start a new thread and list what I have and what I've done.
sbc 400. Bored .030 Ground crank. Pro Max 200 heads. 72 cc. 10:1 CR. Springs will take .600 lift. Howards cam/hydraulic lifter kit .510/.530 lift. 230/234 dur@50. https://www.summitracing.com/parts/HRS-CL110255-12. Accel distributor Non-computer HEI. https://www.summitracing.com/parts/ACC-59130. Holley 4160, 750cfm. A/C double platinum plugs 41-801. New battery fully charge. Everything is new.

I timed the cam when it was on the stand during build. I checked it at least 3 times. And set the valve preload at that time. 1/2 turn after 0 lash.
I have had the valve lash at: Rocker nut 0 lash plus 1/2 turn on nut, 1/4 turn on nut, 0 lash, .010 lash, .030 lash. And with each I've had the distributor turned from one extreme to the other. I even turned it 180, that was obviously not it. I have had it running twice. It misses/stumbles bad and slowly starts running better if I can get the rpm up to 1500 or more, if I can get it running. It sounds like it's running on 3 cylinders. I have had it idling and took it for a ride. The next day it won't start. I have 12.7 battery voltage at the distributor.

I will try to add a video. I've never had a problem getting an engine started. Any help, guesses, take stab at it. Thoughts, Ideas.

 

I couldn't post a video on here so go to my fb. It won't let me do that either. fb jim sisler

 

Since I had it idling at one time I would rule out mechanical. What do you think? What would you check? What would you do? Please comment.

 

I don't know if you can see my facebook video. It doesn't let me post it here He it is. Take out the spaces.
facebook. com/ jim.sisler.5

 

Are you sure you have your firing order correct?
Are all the spark plug cables the same resistance if you test them with an ohm meter?
Have you verified spark at each plug using a spark tester?

have you taken the valve covers off and verified all the lifters are moving correctly? are they moving the same distance?

What is your timing mark showing when you spin it over?

Fuel, Spark, Compression, and the correct timing is all you need to get it to spin over.

 

THANK YOU for giving me things to check.

Firing order: 18436572
Plug wire resistance:
1- 4.3 2- 2.0 3- 1.1 4- 1.1 5- 1.7 6- 1.1 7- .9 8- .8

I tried a different set of known good set of wires but no luck. All the valves/rockers are moving I didn't check actual amount of movement. I had the timing at about 10 btdc but I have moved it since. Like I said I had it idling at one time but the next day it won't start again.
I'll have to get a new plug wire tester and give an update.

"Fuel, Spark, Compression, and the correct timing is all you need to get it to spin over."
I know. That's what's so frustrating. It should fire right up. Thanks again.

 

Have you tried using starting fluid to see if it coughs to life? That could indicate a fuel problem. Not carb cleaner, actual starting fluid with oil in it.

Edit: maybe a really dumb question, you checked compression already?

 

I checked the distributor today. The coil primary & secondary ohms, checked the pickup ohms, all in spec. And checked to see if it's pulsing, it is. I didn't try to start it today. I have tried starting fluid, no change, no start. I did not check compression but when turning over you can tell it has at least some compression. Remote start switch is on the way so I will check compression and spark at each plug when spark checker gets here. I appreciate the ideas. Keep em coming.