I assume you are talking about the new Hemi motors, as I am pretty sure the old ones would be too wide. I dont know how wide the new Hemi's are, but as long as the dimensions fit, it should work. It will need a full standalone engine controller though, which is $1000 plus right there.
I am assuming he means the Hemi V8's from Chrysler, I doubt any of the big cast iron engines will fit from the 50's to 70's, but the newer engines may, but depends on the width.
The design is not hype... it's proven technology. There are quite a few engines that were larger than the HEMIs of old, that didn't make the horsepower the HEMI did. Bragging rights came from the power that proved the design. Any engine with a hemispherical combustion chamber makes it a HEMI, but they cannot call it one, because Chrysler owns the rights.
If a hemi engine was that much better at power production like the claims make it out to be, then why don't other factories make more use of it? Who besides chrysler makes a hemi engine? Just because an engine has a hemisperical combustion chamber doesn't make out to be the big whoop.
You mean other manufacturers like Alfa Romeo.Aston Martin,Ford,Jaguar,Lancia,Lotus,MG,Porsche,Mitsubishi,Yamaha,Toyota [2tc for example},Fiat,Peugeot,and countless others?