 Removing the flange bolts...  Removing the flange bolts from underneath the car made the passenger-side manifold easier to take out from above. The header also installed from the top, which was a welcome surprise. |  The new shorty Tork-Step headers...  The new shorty Tork-Step headers ensured that there would be no issues with speed bumps. The tubes are stepped up from 1 ½ inches to 1 5/8 inches to improve the flow of the exhaust pulses and expand the torque curve. |  Swapping to headers can sometimes...  Swapping to headers can sometimes pose a problem when remounting the accessory drives. The cast factory lower A/C bracket (right) will not work with the headers. Fortunately, Hedman offers new brackets that prevent misalignment woes. |
 The Hedman bracket mounts...  The Hedman bracket mounts in the same location as the factory piece and allowed our A/C compressor to align without trouble. |  Our Malibu must pass an emissions...  Our Malibu must pass an emissions test, so we added Hedman's Performance 2000-series catalytic converters. These will fit most 2 ½-inch exhausts, flow more than 20 percent better than stock, and are CARB legal. We suspected that the original converter was very obstructed after more than 100,000 miles. Note that a catalytic converter cannot be replaced until the vehicle accumulates more than 50,000 miles. |  Due to firing-order pressure...  Due to firing-order pressure differences, when two neighboring cylinders fire consecutively, their exhaust pulses fight each other to get out. The X-Treme Crossover kit allows these pressures to cross over into the other pipe, improving the flow of spent gases and boosting engine performance. |