Just a clarification .
Poly , yes in hindsight i would do a semi circular insert . It would then be broader and may less affect air flow ? My thought was to split/direct air outwards towards ports rather than just smash the large flat floor area .
The insert was a fully sealed tube welded to intake floor . So equivilent to a solid bar .

B1 , here are the dyno sheets again , this time in color plus a chart to compare to single 4 barrel . Pull with no filler is pink , 2nd sheet pull with filler and spacer is pink no spacer is blue .
Pull with filler shows a TQ loss .
BUT i will say the dyno operator would often play with ramp speeds and this will affect readings . Did this affect TQ not sure . This was 10 years ago . Also they have very different correction factors listed .

Tex