I had a '98 V-6 before I traded it for my GT. I really liked the car and wish that there were someway that I could have kept it and bought the GT too. Anyway, I would buy a Borla or Magnaflow V-6 cat back. They are stainless steel, fit great and will last the life of the car where a Mac or Flowmaster system will rust over time and have to be replaced. I have read bad things about the fit of Mac on these and other boards. I had a Bassani system on my 98. The fit and quality were top notch but I did not like the sound. Also, I had installed a factory rear sway bar on the car and the right side tail pipe interfered with it. The sway bar was given to me free so I ditched it and kep the cat back. I also ditched the 2.73 gears and installed Motive Gear 3.27's. The gears made more of an impact on performance than the exhaust. The car was much more responsive and the gas mileage stayed the same. Brother's Performance catalog has V-6 performance parts such as pullies, throttle bodies and cold air systems. Steeda has a V-6 cat back and cold air system. If you really want to make your V-6 fly, check out Super Six Motor Sports in Georgia.
www.supersixmotorsports.com. They have ported heads, ported intake mainfolds, cams, blowers, chips etc. If you have deep pockets check them out. Enjoy your 98 V-6. I did mine and miss it sometimes.
making my 1998 v6 go fast and sound good 
