Carburetors or EFI?
Discussion has been circulating at that local hang-out between car enthusiasts over what type of fuel delivery is better.
Carburetors have been around for over a century. This is a device that, simply put, delivers the amount of fuel an engine needs in relation to the amount of air that is pushed through it by atmospheric pressure. Carburetors work on a pressure-drop principle in which I will not go into great detail other than when tuned properly for atmospheric and weather conditions, carburetors work very well.
There are many types of Electronic Fuel Injection on the market today. I will touch base on 3 major types known as: Throttle Body Injection, Port Fuel Injection, and Direct Fuel Injection. All of these systems are controlled by very similar computer systems and related sensors.
Throttle Body Injection is the most simple type of EFI and the closest to carburetion in operation. Fuel is injected above the throttle blades by one or more fuel injector nozzles. Both fuel and air are carried throughout the entire intake tract.
Port Fuel Injection is the most widely utilized form of injection today. Fuel is injected at each intake port, usually at the cylinder head and intake manifold. Only air travels through the intake tract until it reaches the point in which fuel is injected. This method allows a wide variety of intake system designs to be explored and utilized depending on application, thus making super- and turbo-charging extremely feasible.
Direct Fuel Injection is a new technology. This system utilizes injectors similar to diesel engines in which fuel is injected directly into the cylinder. Obviously cost is high due the custom cylinder head configuration and high-temp injector required. Not much is known about this system relating to performance usage be the foundation has been laid for previously untold amounts of attainable power potential.
CARBS vs. EFI
The real question: Which is better? Well, this depends on a lot of factors. For one, what do you do with, and how do you drive your car? Obviously, if you race a vehicle professionally in which rules are involved that restrict the type of fuel delivery that can be used, you have little choice.
The age old question has always been disputed: Which makes more power? Well, this too is a good question. Carb enthusiasts argue that carbs make more power over port injection because the fuel helps "cool" the intake manifold. If this were true, what about Throttle Body Injection? I have seen little evidence to prove that carbs out-perform port efi on identical engines and vice-versa in controlled conditions.
Again, your choice depends on what you plan to do with your vehicle. In my opinion, carbs work great in ideal weather conditions and areas of the country which see little climate changes. Unfortunately, there are rarely 'ideal' conditions present. This leaves you to change jets and tune your carburetor to the changing weather conditions as the day goes on. On the other hand, EFI systems automatically compensate for changing conditions.