When considering an engine swap, you must first decide what it is you need. For instance, a Chevy V8 may have incredible power, but when you put it in the rear of a VW, the handling is dangerous, the gearing is too low, and your new $2000 supertrans will grenade if you drive it hard. It pays to explore your options. Some things to consider when planning an engine swap are:
Your Resources
Type of Vehicle
Smoothness of Engine
Radiator Location
Your Aptitude
Type of Driving
Strength of Transaxle
Clutch Needed
Your Budget
Mileage Desired
Weight of Engine
Starter Required
Power Desired
Engine Mounting
Height & Length of Engine
Smog Laws