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16. We headed over to Westech Performance and strapped the newly revitalized ZZ4 engine to the Superflow dyno, filled the tank with pump gas, and fired it up. Once properly broken in, Westech’s carb guru, Steve Brule, started making pulls and performing adjustments. Over the course of a dozen pulls, he gradually added timing, installed a lighter spring for the vacuum secondaries, and swapped the jets around. On pull 13, we were rewarded with our best corrected numbers of 413 hp and 415 lb-ft of torque. That’s more power than the ZZ4 made stock, and we did it with less compression and on a lower octane gas than GM recommends. As for torque, the peak isn’t much higher than the ZZ4’s advertised number, but we really like the flat curve and the fact that it made over 370 lb-ft of torque way down at 3,000 rpm. If we didn’t mind upping the compression and running the more expensive swill, there was even more power to be had, but we still remember when a 400hp engine was enough to make us smile.