I have wondered about these heads, out of curiosity, for a while.  Big valves low compression 82 cc chambers.  What was their purpose?  Were they a replacement for the EDB-D and E heads used with superchargers, and recycled into '59 vehicles to get used up?  How did the trucks and unfortunate Mercurys run with the 471's?  Finally, were the chambers open, or was there a quench area?

Mike

Mike, located in the Siskiyou mountains, Southern, OR 292 powered 1946 Ford 1/2 ton, '62 Mercury Meteor, '55 Country Squire (parting out), '64 Falcon, '54 Ford 600 tractor.