Could you please let me know which engine is good on fuel (EFI vs VTec) and also what is good for performance ?
Main differences and Advantages ?
You cannot compare EFI with V-TEC both are totally different technologies doing totally different things.
EFI means and I am assuming Electronic Fuel Injection. As the name suggests , it helps in injecting fuel to the cylinder through electronically controlled injectors without the use of carburetors. This massively helps fuel efficiency over the carb version of the engine.
Vtec on the other hand is Honda's way of implementing Variable Valve timing(almost) , it basically uses two camshaft profiles and an actuator to determine which type of valve life and duration change is necessary for which particular moment. So meaning it gives the engine two camshafts, below a set RPM say 4500 you will have a economy mode with normal fuel saving everyday camshaft, above that set RPM the performance camshaft profile will kick in giving you more power to perform overtaking and such.
So as you see there is No way these two totally different technologies can be compared to determine fuel efficiency or anything for that matter.
If I understand your abbreviations, when you say EFI you mean Electronic Fuel Injection? I would say pretty much every car made in that last 25 years uses EFI, as opposed to the older technology of carburettors. This does provide better fuel economy.
Honda's VTEC also helps improve economy:
VTEC (Variable Valve Timing and Lift Electronic Control) is a system developed by Honda to improve the volumetric efficiency of a four-stroke internal combustion engine (i.e. improved economy).
There's not really anything to compare and contrast, as they are complimentary technologies; it's not like it's an either / or situation. In fact, I'm pretty sure that every car that has VTEC also uses EFI.