Trouble starting '71; have fuel, spark, engine cranks

[Son of Marty]

Are those numbers taken with all  4 plugs out and the throttle wide open with a charged battery?

[johnnyb]

5 hours ago, Son of Marty said:

Are those numbers taken with all  4 plugs out and the throttle wide open with a charged battery?

All plugs out, battery fully charged, but I didn’t touch the throttle. 

[Son of Marty]

Throttle needs to be opened all the way.

[johnnyb]

I still plan to re-measure the engine compression, but I'd like to close out this thread and thank everyone for their help.  After going through all or most of the suggestions, the car has started up with only a few cranks  on several occasions!  More importantly, I've learned a lot about how to tune this car, how to use the manual choke, and the carb is no longer a black box to me.  I don't know what (if any one thing) was the one that solved my problem, but collectively I feel I know this car better and can trust taking it on longer drives.  Now onto the other things the car needs...

 

   Thanks to everyone who chimed in on this thread and offered help or suggestions on what to try! 

 

    John B.