summerwind

going thru the TeeDee 049/051's i have tonight and noticed that the early model engines i have from the early 60's have a smaller diameter hole in the venturi than the later mid 70's on up with the screen..........not an exact dimension, but the early ones seem to have a .070" versus the later which are close to .110" hole........did Cox increase this dimension due to the screen?
will removing the screen hurt the suction?