Tuning help, please

Darter6 said
I looked in my 66 service manual and it has 3 different timing settings for 2bbl,4bbl,auto and manual.
2bbl manual shows 5* BTC .2bbl auto shows 10* before. Now get this,cars with cleaner air package ,2bbl manual or auto
its 5* ATC.

The 4 bbl auto or manual shows 10* BTC if it has the cleaner air package auto or manual its 5* BTC
Click to expand...
Cleaner Air Package vehicles got distributors with mechanical advances that compensated for retarded initial.
The retarded initial put more heat into the cylinder walls, insured more HC was burned up, and reduced CO.
A graph illustrating the 273 CAP vs non-CAP timing in this post.