Good ideas All:
In review of all the responses, and pondering on all, have come to conclusion the best solution in this instance is to
1. install front dam, frontal area gaps such as between core support and rad are shielded on front side forcing air into rad
2. vent areas behind core support to lower pressure, have removed fender apron extensions (which are heavy ~1/8" rubber panels)to cut down down on noise
3. fab front facing scoop for incoming cool (precharge) and double pass intercooler (freestanding horizontal mount),
Banks does not list a cooler for the old 91 F-250. The listed are all front mounted and still has all plumbing nightmare. Will be using air dam as you suggested, Yes is old brick at that. Also changing out diff ratio to 4:10. Present 3:55 results 1950 RPM= 70MPH in top gear! Good at road speed, but really pooches belly button out when backing on soft soil when trailer loaded.
MadBill S. Bretz & 2Seater
I did not know Kent Moore was still in business. Perhaps is another KM as remember them in the 60's providing auto body shop aids.Will ponder manometer experiment for another time.
Yes as slow as this will be going, think there will be lot of turbulent, but think 3" high intake should suffice to provide positive flow.
NASA website has wing simulator program to play with that gives one idea of flow over various configs. Find attached link for any interested. Can invert/alter shapes
to use for auto down effects with little adjustments to program.http://www.grc.nasa.gov/WWW/K-12/airplane/foil3.html
The down side to this configuration that when stopped/idling air flow may be negative and engine compartment air may be backing up as MadBill said. (I have not had good luck with mounted electric fans.)
My humble understanding of the charge cooling premise indicates double pass non stacked coils type cooler to be more effective than radiator "selective flow" type at speed.
Am sure have forgotten to address all areas and issues,but will find when installing.
Thanks to All.