Is a Holley Sniper EFI system really better than a classic carburetor?

Davin is a man all about making things better, whether that is a neglected engine sitting in a field or a hot-rodded straight-eight. The goal is always to get cars running tip-top, all fueled by elbow grease. In his work he’s heard a lot of myths and automotive urban legends, one of which is that a traditional carburetor is better than more advanced electronic fuel injection. So, of course, he decided to put the two systems to the test.

This is a companion discussion topic for the original entry at https://www.hagerty.com/articles-videos/articles/2020/02/12/holley-sniper-efi-system-vs-a-classic-carburetor

Really interested in hearing about the longevity of this versus the carburetors.

I know that most carburetors weren’t built with ethanol fuel in mind, I imagine this fuel injected setup is, though?


at 16:40 Davin states the AFR will be held at the ideal point (14.7?). However, does this mean that the AFR will not go rich when you hammer the gas pedal? Best performance is not at ideal AFR… nor is best economy.

I’d have thought that managing the AFR at different loads would be ideal, please clarify, thanks.

Would a single plane I take manifold work better I don’t have a lot of clearance for a spacer on 68 cougar thanks Mike

@mjg7623 - Yes, a single plane manifold is best for a system like this. If the spacer does not work, you can remove the intake and machine out the divider in the plenum (only need to go about an inch down) or replace the manifold with a single plane.

Personally I would elect to replace, especially since the manifold is coming off the engine either way.

These systems are dynamic, in that they’ll know the “ideal” AFR based upon engine load, rpm, temperature, etc. Just like fuel injection in a modern car, the Sniper system will richen up the mixture for power production (and detonation resistance).

Great info, please keep these stories coming :slight_smile:

I’m glad that Holley is offering this. I recall these throttle body F.I.'s from their first use in GM and Ford’s back in the 1980’s. They were reliable and if you did need a new injector it was easy to replace. I like the system Davin installed here and think it will interest a lot of guys that enjoy a trouble free turn-key operation. Particularly so if they have a vintage car that sits around for long periods and our ethanol laden gas dries out in the float bowl.
Answering the title question “Is a Holley Sniper EFI system really better than a classic carburetor?” Yes of course it is from most angles I can think of. However, that’s given someone has the money to spend on the HOLLEY F.I. Starting out at $1000 is a lot of money compared to a carb. Hopefully as time passes the cost will come down.

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If the Sniper system is the same as the Holley Terminator or HP/Dominator systems, then there is a small hand-held device used to adjust the trims. This means that after self-learning, the user can go into the software and adjust AFR for cruise, WOT and other load variables to allow for more or less efficiency depending on the user’s needs/wants.

FWIW, when we did the Hot Rod Power Tour a few years back, following behind the carb powered cars nearly suffocated us with their emissions fumes. After awhile, it was too much. However, it was a delight to follow the newer FI cars…

Holy Cow there’s a lot more mods to installing EFI than simply bolt-and-go! 50 psi fuel pump…block-off plate for the mechanical pump…all new ignition…spacer for intake (or all new intake)…Oxygen sensor…fuel return line? (I thought all the fuel went into the engine…there’s leftover that goes back in the tank?)…a sensor to program the system (even though it “learns”, there’s mechanical gremlins that trick the electronics). So we’re looking at $1000 for the Sniper, another $1000 for equipment to make it go, and $1000 to install? Seems a bit spendy for a 10% improvement. And do I really need all that just to make my pre-smog 1950 Lincoln Cosmopolitan more reliable?