Starting issues

[wes473]

Yep that's for a vapor lock canister return line, does your car have one 3/8(or 5/16) hardline running down the body? I believe 440s and hemis had 3/8 & 1/4 with the vapor can. Where the 383 and less had a single 5/16?

[Chryco Psycho]

Usually the second connection is the return line in 70-71 , 70 had a vented cap 71 up was not vented  , later years had the vent line up the to engine breather or a Carbon canister