Project 3-Oh-Why?

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 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 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 in the same location as the factory piece and allowed our A/C compressor to align without trouble.

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 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.