I found one of your previous posts. If it is regarding modifying a 2X4 nailhead intake, nobody in the "F.A.S.T"/Stock appearing class runs a nailhead.
That mod should work on just about any carbureated engine.... and is concealed by the carb.... Grn the Doc dual plane is a mod that I came up with to make the Buick single 4 manifold flow more .... what you do is cut the partitions out from between the front and rear bores of the manifold , leaving the center divider in to keep the torque.....works really good on nailheads,,,, 2/10ths reported picked up..... I have done it on my 64 riv. 425 and 65 GS lark both with good results....
I have nothing to hide, I'll tell anybody that asks about any mods to any of my cars.......... The intake on Amandas GS was done by Gessler back in the mid 90's, one of the mods done is to cut the divider down to increase flow. 2/10's is huge for just some grinding on the intake, would be interesting to put egt's in each port and do a before and after test runs, wonder if the dividers are killing flow or if they screw up the distribution that bad.
We (actually, I paid Gessler to do it) milled down the divider on my Vette to kill of some bottom end torque and help me launch it. It worked for that, but the tuning was a little spotty for street driving after that. I'm not sure if it was the removing of the divider or the amount that we had to slow down the secondaries afterward that made it easier to launch.