Really.. the HP/Liter war in DOHC vs. Pushrod is just comparing apples to oranges. HP is directly related to TORQUE. (If I remember correctly HP = (Torque*RPM)/5252. )A pushrod (or 2Valve) motor will make more useable low end torque, simply because it maintains a higher air velocity at the lower RPMS.
And even if you want to play the HP/Liter game, look at the LS6 in the Z-06 Corvette 405hp/5.7 liters. That's 71hp/liter.. more specific output than a standard 2.5 Liter duratec, and with Torque to back it up!
Also, I'm pretty sure that a stock 5-spd, 5.0 Fox body will do significantly better than 15.2 in the 1/4.
Major Manufacturers use many different ways to make their power. GM tunes their pushrods, Ford likes Roots blowers, Dodge likes turbos and V-10s, Honda has VTEC.. the end result is still good HP.
Who cares how it's made?
