The last time you saw our project '78 Malibu, Magnaflow Performance had just outfitted the family sedan with a free-flowing exhaust, and we were sorting out the last minor details on the LT1 conversion (see "Buttoning Up the 'Bu," Oct. '02). With most of the bugs worked out of the swap, we're ready to do what we love best--bolt on horsepower!
To see how well a late-model LT1 small-block responds to typical aftermarket bolt-on goodies, we ordered a set of JBA Header's Power Cables to replace the worn-out factory spark-plug wires, opened up the air-inlet tract with a High Flow Induction System from Moroso, added a larger mass-airflow meter from Granatelli Motor Sports, and installed a BBK Performance 58mm throttle-body assembly.
Our baseline dyno flogging at Morgan Motorsports' chassis dyno in Reseda, California, generated impressive numbers out of this salvaged LT1, with 259 hp and 291 lb-ft of torque. This was down somewhat from our last session, which produced 270 hp and 299 lb-ft of torque, but we think a change in weather from our last test has a lot to do with it (these are uncorrected numbers). Although the baseline power was down, it didn't affect the comparison numbers for the bolt-ons. We tested each component one at a time and were pleased to find that the fuel-injected LT1 graciously accepted the additional airflow. The new parts combined for a 20hp gain at the rear wheels, and drivability and throttle response improved as well. Read on for the details.
