Not a 383

the 361 is a big block... it was in the low deck family with the 383, and 400

the 361 had a bore of 4.13" and a stroke of 3.375"
for 1966 it was 9.0 :1 compression with 265 hp @ 4400prm
stromberg 2 barrel carb was all that was available on it.

for comparison a 66 383 had a bore of 4.25" and 270 hp and 9.2:1 compression with the 2 barrel