I have removed the sec. cats and the very long mufflers from the car and the interior heat and side sill heat, and I would even say the engine heat under load is reduced dramaticly. This is a must. Do replace the mufflers with Bullet Performance Mufflers, you will love the sound, that I promise. This has to be the ultimate upgrade for the money. No check engine light, or failed emission test, when removing the sec. cats. They are the ones on the side of the car, and they are full of substrate, don't even know why they are on the car, unless Chrysler wanted to keep overall emissions down, but the car will pass with the primary cats on them. I'm sure many cars on the road don't run as clean as the SRT even with the sec. cats off. I'm anxious to see the numbers at the emission test on inspection day. I will do a comparision to other cars just to see.
Skip