Zoomer-
"We did something similar in testing those cores and contemplated making a new IC design. The results were so horrendous that we abandoned the projected before a 3800 design was completed. We were below 50% efficiency and in contrast we were over 80% on generic Ebay cores and over 90% on Spirco.
We also determined airflow restriction was not an issue a long time ago. Those charts are still on the site now. The blower actually puts out more air with the current IC's because boost drop allows easier flow thru the engine."