got more info? budget? limitations? expectations?

the 2 are totally different and cannot even be compared without more requirements...do you want all out power or driveability? EFI/carb? budget?

depending on the car and what it's got now, a big block might drop in with just an all out stroker build costing $5-6K, but if its a small block car, then you need everything to drop it in, and could spend closer to 10-12K

a hemi driveline out of a junkyard could probably be had for less than $5K...but then you have wiring, custom engine mounts, headers, etc. to worry about.