Originally Posted by ten_gigahertz
I heard 'hemi' comes from the cylindar heads being domed... as in hemispherical...
Yep, it'* a combustion chamber configuration more than anything.
I know for a fact that Toyota used this setup starting in the 1960'* and throughout the 1980'*...
1982-1986 Toyota 5M-GE: 2.8L 12V DOHC I6, ranging from 150hp in earlier years to almost 170 in 1986.
"Pentroof" is a similar setup, but with accomodations and changes making it possible to have 4 valves per cylinder. This is what your 3.4 DOHC would be, haro