Looks like a 318 'Cuda.
Do you have the whole Serial number? or everything except for the last few digits?
E44 318-2 Barrel
D34 TorqueFlite Automatic Transmission
BS23 B = Plymouth Barracuda
S = Special
23 = 2 Door Hardtop
H3B H = 340 240HP(net) 1-4BBL 8 CYL
3 = 1973
B = Dodge Main, Hamtramck, MI, USA
xxxxxx Sequence Number 'xxxxxx'
HB1 Paint Code: Light Blue
A6B5 Trim Grade/Style/Color
A = A Class
6 = Vinyl Bucket Seats
B5 = Medium Blue
000 Upper Door Frame: Full Door Panel
C15 Date Built: 12 / 15 / 1972
403302 Order Number: 403302
V6W Roof Type OR Color: White Longitude Sports Stripe
M21 Roof Drip Rail Moldings
N25 Engine Block Heater
U Built to Specifications for USA Order
B41 Front Disc Brakes Some Yrs. Power
C16 Console w/ Buckets
M31 Belt & Hood Molding
M28 Front Bumper Periphery
R11 Music Master Radio AM
J52 Inside Hood Release
J54 Hood Insulating Pad
L25 Trunk Compartment Light
C56 Bucket Seats 1972 up
G27 Unknown At This Time