The 425 Buick Nail head from a 1966 Buick Electra 225 last ran in 2008 but it has been stored inside and it ran well then.
In preparation for install into the Gasser I power washed the engine and transmission and removed the distributor and used a tool to drive the oil pump. The oil pressure was at 40 PSI so I changed the oil and filter and rechecked it (OK) and ran the pump for a few minutes.
I removed all of the spark plugs and put a few squirts of Marvel Mystery Oil in each cylinder and let it soak a few days. I put a few more squirts in and rotated the engine with a breaker bar on the balancer and the engine turned over easily.
I checked the compression of each cylinder with my tester and ran the oil pump before I did each cylinder in order. The compression varied a little between a high of 180 PSI on 3 cylinders, 175 PSI on 4 others and a low if 160 PSI on 1 cylinder ( 88 % of the high reading). I will recheck later and see if there is a ring or valve issue when I pull the valve covers.
I plan to see if the engine will start after I check and reinstall the Carter AFB carburetor and new electronic distributor and coil.