NHRA Expands Factory Stock Showdown

[Pedigo Perf]

Originally Posted by GarysZ24

If there's no advantage to EFI's over carburetors, then how come small block EFI engines are the performance equal to carbureted big blocks? Moreover, how come all production vehicles come with computers and no longer carburetors? They're more efficient in extracting more power from the same (or less) amounts of fuel. My EFI '04 Colorado does a better job with only 5cyl's of towing my Cavalier around (on less fuel I might add), than my '77 half ton 350 V8 carbureted Chevy Full Sized truck did back in '99 (it also was rated 45hp more). I'm not going to challenge your mechanical knowledge, but EFI put carbs in production vehicles to RIP status, thus proving the merit of what I stated as well...

EFI was implemented by the car makers to make it possible to achieve the emissions requirements imposed by the EPA. Simply put, the required feedback system (oxygen sensor measuring and reporting the mixture) is much more easily controlled by a PCM pulsing an injector than the limited range of a carburetor and the inconsistencies that come with it. Setting a bi-metal spring operated choke for all conditions is virtually impossible, just for one example. A PCM, if programmed properly can easily handle the task of good cold starts and drivability in Denver or that of a 100 degree day in Tulsa.

Power is about airflow and the amount of fuel and oxygen you can combine in the chamber. IMO, a properly tuned carburetor can handle the task just as well as injectors assuming the airflow is not compromised. I have not seen significant gains by replacing a GOOD carb with a throttle body and electronic injection as far as full throttle performance is concerned. Where the injector really has an advantage is that it allows for a wider range of intake manifold design and throttle placement. If you notice the fast small blocks you refer to have a lot of technology in the cylinder heads and intake manifold that compliment the injection system.

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