Five of the most underrated engines and their true power

You might think that it’s advantageous for an automaker to always claim the highest possible output they can on their engines. But sometimes, in order to get lower insurance rates or sneak into certain racing classes, manufacturers underrate their engines and say they make less power than they actually do. Naturally, this leads to a lot of talk about what engines “really make.” Well, the talk can stop here because we’ve gathered the facts on five of the most notoriously underrated engines of all time.

Chevrolet L88 427

This is the meanest “rat motor” of them all. The L88 used a high-overlap cam and a crushing 12.5:1 compression ratio to become one of the most powerful engines of the muscle car era. The engine was laughably underrated at 430 horsepower at 5,200 rpm but GM wasn’t completely dishonest.  The engine actually did make 430 horsepower at 5,200 rpm, but GM neglected to mention that its power peak was around 6,500 rpm where it made over 500 horsepower. As can be seen in the video below, a stock recreation of an L88 engine made 557 horsepower. It’s worth noting that the engine in the video doesn’t have parasitic losses like a power steering pump or full exhaust system, but the true output of an L88 at the flywheel when fully dressed is around 510 horsepower.

Verdict: Underrated by 80 horsepower

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