The MagnaFlow Tru-X system was a direct bolt-on replacement for the factory cat pipe. In addition to the stainless steel construction, the Tru-X featured provisions for the four oxygen sensors (before and after the cats). The system bolted to the factory exhaust manifolds and even relied on the factory mounting brackets (on the tranny mount).
After the installation of the new Tru-X system, we were instructed to take the car out for a quick drive to burn off the coating applied for shipping and storage. The power gain was immediately evident from behind the wheel. We were impressed that the power seemed to be better everywhere, not just at high rpm. The Dynojet verified what our backsides were telling us, with the peak power up by 11 hp, from 199 to 210 hp. Elsewhere along the curve, the power gains were up by as much as 12-13 hp. The torque gains were equally impressive, with the peak up to 281 lb-ft from a maximum of 268 with the stock cat pipe.
Given that the factory cat pipe was the restrictive component in the exhaust system, we expected little power gain from the axle-back exhaust. Taking nothing away from the impressive MagnaFlow performance after-cat exhaust system installed on our '96 project car, the reality is that even having no system would be of little benefit at the current power level.
That said, the reason behind the installation of a new after-cat exhaust is more than just power. While the Tru-X cat pipe offered a slight change in the exhaust note, the real change came once we installed the new MagnaFlow stainless steel after-cat. We know the flow gains offered by the MagnaFlow will come in handy once we up the power output with cams, ported heads, and a new intake, but for now we would be satisfied with an improvement in sound quality.
The new system offered stainless steel construction (to ensure a long life), ease of installation (things were well labeled and fit as promised), and a throaty (but not overly obnoxious) sound quality. The kit came complete with everything needed to perform the installation, including a pair of different exhaust-tip mounts to work with the different model years. The polished mufflers were almost too nice to install under our high-mileage machine.