Reply to "351c EFI intake manifold"

It doesn't apply to supercharging DT.
If you have a supercharger that kicks in at a low rpm then you want short runners in the intake.
If it doesn't kick in to say, 3,500rpm then you have sort of a hybrid induction in that you need the naturally asperated part of the system to provide as much torque as it can by using a long runner until the supercharger kicks in then you want as short runner as possible to reduce turbo lag.
The killer turbo systems use two small units that kick in right over idle, maybe 1,500 rpm.
The turbo has to be sized, or "tuned" to the set up to provide quick respose (that means a small turbo) and enough boost to go to the rpm limit that you want.
In your case that's about 12,000rpm right?
Good luck with that one.
You will need a set of staged turbos to kick in as you go through the rpm range.
I have a friend with a SB Chevy that runs in the 40psi boost range.
He has to let off of the accellerator to move the shift lever.
Last time I heard he was at 1000hp and kept breaking input shafts.
I just don't understand why, do you?