Well if you put a modern LS1 or the like, or the Mitsubishi turbocharged 4-cyl that I'm partial to
, in your car I'm guessing you would definitely see faster times. This Hemi thing seems to have even guys that talk about cars for a living fooled. I was watching that show on Speed (I think) where a couple people sit at a table and talk about the auto industry and what car manufacturers are doing. One guy says "well with its Hemi engine the new (insert Dodge, Jeep, etc here) will out power the competition..." or somthing similar.
Progression of engine designs:
Steam?----->Flat Head----->Hemispherical----->Pentroof----->?