If you look at the numbers on the graph and compare them to ones in the text, you'll find they don't agree. For good reason-the baseline test on the graph was done before the speed limiter had been raised, so the engine never reached the rpm at which it makes peak horsepower. That's a trick played by some tuners to make it appear as though they increased power more than they actually did. Note the difference here is 40 horsepower. After we eliminated the speed limiter restriction, the difference was only 24 horsepower.