How were early 70’s V8’s so large yet relatively lacking in power

Question

How is it possible with the Chevy’s and Caddy’s with their pure American 6 litre V8’s didn’t get past 300 horsepower.

It seems so implausible that such a massive engine was so inefficient.

In: Engineering

Answer 1

All in the name of fuel economy and emissions control. Big engines don’t make big power if you don’t give them lots of fuel and let them breathe well. ELI5.