Replacing the 225 heads with the slightly smaller 210 resulted in identical power curves. Obviously the 302 could not benefit from the extra airflow offered by the larger 225 heads. Our final test before catastrophe struck was to install the as-cast 190 Pro 1 heads. Run with the 190 heads, the 302 produced 390 hp and 373 lb-ft of torque. Though down slightly in peak power, the 190 heads offered better power than the 210 or 225 heads from 3,800 rpm to 5,600 rpm.