One of "my" 422s is mild. hydraulic flat tappet, factory ported heads, factory rods, even the Eagle cast (the last one I used...).Going by the weight and MPH it makes around 460hp at the crank, runs on pump 89, and in the same car gets over 17mpg on the highway (3.23 gears). And that's in a heavy E body (3900lbs) with a 727 in it.
With every build - big, small, 8 cylinder, 6 cylinder, 4 cylinder - it's about the combination. Not size. Examples:
Naturally aspirated my Neon 2.0L (my porting on the head, minor milling, intake, exh manifold, and throttle body cleaned up/ported, cam timing optimized) makes about 180hp from 122 cubic inches or 1.48hp/cu inch and with the 5sp gets about 34mpg on pump 93 driven stingy.
Naturally aspirated that 422 makes about 460hp from 422 ci, or 1.09hp/cu inch and makes 17mpg.
Naturally aspirated 505 ci, makes about 580hp or 1.15hp/cu inch and gets about 14mpg with 3.54s and a 4sp (no OD) with a 6bbl again - in a heavy E body rag top (4000lbs)
Choose your poison.
