I'd say that maybe a carb is something that the average fan *thinks* they
can relate to, but the reality is that very few people are competent to do a
significant carb repair properly, and even fewer would understand and
appreciate the differences between the average Holley toilet bowl and the
handcrafted jewels that sit atop NASCAR intake manifolds. They call them
carburetors, just so people think it's got something in common with the
things that used to be under the hood of their land yachts.
Top end power is governed pretty much by the amount of air mass you can jam
into an engine and how evenly you can mix it with properly atomized fuel. At
high flow rates, a carburetor can do that just as well as fuel injection or
vice versa, especially if you assume that a proper effort has gone into each
system to equalize the mass flow volume to each cylinder. But the fuel flow
delivered by a carburetor depends on the atmospheric conditions as well as
things like the float bowl fuel level etc. Once the car starts moving around
and sloshing the fuel in the float bowls, the mixture is going to be upset
to some extent. Then, when you start varying the throttle opening, RPM, and
environmental conditions, it quickly becomes very difficult to design enough
compensation circuits into the carburetor to cope with it all. The EFI
systems of today can do it much more effectively with appropriate use of
lookup tables for compensation factors, and advanced feedback systems using
exhaust oxygen sensors.
So... For a given engine, part-throttle drivability is easier to control and
maintain with an electronic computer than with an air computer. This is
especially noticable if the engine is designed to perform at high RPM levels
and so it doesn't have gobs of torque at the low RPM band to begin with.
Best regards,
Theo
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