"E" engines came in two different horsepower ratings.The 270 H.P. used the regular "D" code cam that came in all of the 312 engines.
That is part# B7A-6250-B.That part # has been superceeded to a lamer camshaft B8A-6250-C.
The "E" code 285 H.P. version did indeed use the blower cam.That is part#B7A-6250-C.
I have recreations of the original blower cam unit for sale if interested.
You can read about it in this link.
http://www.y-blocksforever.com/forums/Topic31665-7-1.aspx?Highlight=oldmics
Oldmics