Stock muffler ?

It's going to leave your exhaust very unbalanced. You'll build up extreme backpressure, and heat the hell out of your exhaust manifolds. Just keep it as it is now and stay very low RPM when cops are around.

so it's bad to have a o/r X-pipe mated to stock exhaust? Could it be like this for say.....a month or 2?

<---rysred96gt

actually, the stock muffs flow pretty well. it looks like a dynomax muffler but not as smooth-flowing.

Go ahead and put the stock mufflers back on. It should tone things down a bit since flows are kinda loud. Stock mufflers vs flows will leave you with a little decline in hp but you probably wont notice it. Should have went with a catted system if you didn't want too loud.

Its not all that bad flow wise, but you need to think about it from where all the sensors are located. Now I am not saying you guys are wrong here, but I was going to go with the setup you were suggesting. I work for Ford, so I asked the techs what they thought, and then asked a ton a muffler dudes. You want your pressure to flow at a constant rate. If gases are leaving the manifold at a high rate (no cats), then slowed down, you'll really bake things up under there. You could possibly even have heat back up into the exhaust chambers. OEM muffs flow great for stock, but are not complimentary components as a very high flow X or H. I would suggest Dynomax ultra flows; they are very quiet mufflers, yet flow amongst the best, if not the best.