Installed the C&L Plenum on my 98 GT today. Only other mods I have are series 40 flowmaster and a UPR offroad X-Pipe without cats and a MAC CAI. Tried the C&L with the MAC CAI and it made my exhaust quieter. Really like the C&L Plenum. Pulls alot better in 3rd and 4th over 3000 rpm. Kept the stock TB. Could not see spending the extra $200 for 2 HP since I only drive this car on the street. Took off the MAC CAI and put back on the stock pipe with a K&N and silencer removed. Exhaust tone is alot better and I can tell no difference SOTP between the stock pipe and the CAI. I am leaving the CAI off, this thing just gets too damn hot. I think the CAI was all in my head when it came to SOTP feel.
Just my 2 cents.
Just my 2 cents.