DO NOT run no mufflers, trust me, try it for yorself, youll like it for 5 minutes of driving around, then youll be embarrased to be driving that thing around, its SO loud and it sounds SOOO bad, like a dump trck. You can try it, get under your car, spray some wd40 on the bolts that connect the catback to the mid pipe, and take off the 4 bolts. Move the catback out of the way alittle to open them up and fire it up, you will be flying home to put it back on, ive done it, i always thought i wanted the loudest possible exhaust, and i still do want a very loud exhaust but NOT no mufflers. If you want loud, run an o/r mid pipe, and weld some dynomax race bullets in there, that will be LOUD and have tone. Sorry if its long i just cant express to you how bad it sounds without mufflers.