[Steve C.]

"EFI throttle-bodies are different than carburetors because they don't need a "signal" to get the air/fuel charge moving. And in a port EFI system, the intake is dry; there's no fuel through the throttle-body or intake runners to fall out of suspension. But there's still the issue of total system volume versus engine airflow requirements, so in that sense spacers could still prove to be of benefit on EFI setups, although less so than in a traditional carbureted application."

Source:

How Carburetor Spacers Affect Performance

https://www.motortrend.com/how-to/pi...t-performance/


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