As Andy pointed out, engine dyno tests are not always a good indication on how those motors will perform in the car
The torque converter, exhaust system and every other part on the car contributes to the in car feelings
One of my old pump gas Duster(that I traded to 9second Phil) with a mild 360 motor and 4 speed ran mid 14.40 at LACR with 3.55 gears and slicks, we swap the third member to a set of 4.89 and the car felt way faster on the street, at the track it might have pickup .2 ET and maybe 1/2 MPH
My other bracket Duster picked up .8 ET and 7 MPH by changing the carb. from 600 DP on a Eddy TM7 intake to a 1050 Holley Dominator carb. and Mopar M1 4500 single plane intake manifold with no other changes
Theory is one thing , real world results are different
I should add, put that motor in the car and go drive it and flog that rascal a bunch Have fun