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We tapped into the ECM of our '01 Trans Am to see if tuning practices had changed with current technology and emissions regulations. Using an OBD-II-compatible diagnostic-scan tool, we found that at normal operating conditions, our LS1 idled with 22 degrees of advance, and it peaked at 38 degrees at part throttle. Consider that the cylinder heads of these engines are designed for the quickest possible burn, as you can see in this LS1 chamber shot with its heart-shape and spark plug biased toward the exhaust valve, among other features. As a result, maximum full-throttle performance requires just 28-30 degrees of advance.