I had one on the 509 cammed, iron headed 440 that I had in my cuda years ago. It ran 11.40s at 117 mph at 3700#. I found a 1" open spacer made a little more power. I did some mild blending of the flat spots at the top of the flange after I put the spacer on, but that was it.

CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 18 spline 4 speed, Dana 60
'71 Demon, 340, low gear 904, 8.75
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax