Just wanted to share my comparison of these two kits. 15882 is the axle back assembly and 15881 is the axle back + mandrel bent pipes to your stock Hpipe. The 15882 kit will give your car a nice, deep tone. Louder than stock, but not extremely loud. I really liked it. Hp gain...none that I could FEEL. 15881 kit....gives your car a deep tone, and you can feel a rumble in the exhaust system. Very nice, very 'muscle carish.' You CAN FEEL a Seat of the Pants difference in power above 3500 RPMs. The car feels a good bit quicker and louder. You may have to have an exhaust shop install it though because getting out that over the axle pipe is a real PITA, unless you can get your car 2.5-3' off the ground. I bought both kits from Sourappleperf.com
I had the same mufflers on my Black GT and my Grabber Orange GT with a Pypes Off-road X pipe. It sounded pretty nice... Here's my Black GT with that set up... YouTube - My 07 GT w/ Pypes Offroad X Pipe and Magnaflow Axle Back Nick
You can buy those systems from StangNet's sister site Magnaflow Exhaust - Home ... if you've found a system cheaper than we sell it for use the make offer.
Those are really nice kits, good quality in materials and the tone is perfect very muscle car-"esque". LOL
