[Bob Lincoln]

Bad rings will do that. Do a compression check, squirt oil in the cylinders and test again. Increase in readings indicates bad rings.

 

[dana44]

Another thing can be a blown power valve or too large a power valve setting, so constant fuel running into the intake. Do you remember what power valve number was installed and what your vacuum reading is at idle with the vacuum advance plugged off?

 

[tazdevil]

Inspect the fuel pump for a cracked diaphram. That willleak fuel into the block. I agree with the power valve probability,too. They die easily. The corect power valve number is measured manifold vacumm times two. 16 inches means 32 power valve.

 

[dana44]

Correction on the proper power valve is vacuum divided by 2 plus two. 16 inches divided by 2 is 8, plus 2, so a 10.5 power valve will be correct (as an example)