Okay so i want to make a mid pipe but im not really sure if i can just use a straight pipe?? Would i need a cat or anything like that??? my dad is a welder and he has his own shop so i was going to do it there...

Does after market Mid pipes really even help flow and HP would it change the sound of my car very much???

And one more thing instead of making a mid pipe should i just buy one??

I was looking at this one

http://www.frsport.com/Megan-Racing-...tC_p_5491.html

 

I can vouch for that Mid Pipe being a nice piece. However, if your dad owns a shop and can weld well, then you'd save a bundle just having him do whatever it is you want. What do you have done to your car and what are your goals? If you plan to add a header, you'll need two resonators to get rid of the horrible rasp. I like loud exhausts but holy crap, do your county a favor and get two huge resonators. If you're going to leave the stock header on, you can safely ditch the secondary cat and resonator and put whatever axleback/muffler combo you want.

A true baffled muffler (not flow through) will give the best deep tone and the flow through's give you the rice sound, although that's not always bad depending on the note. I prefer the baffled for my setup. I run a "sleeper" if you will. Near 300 whp and whisper quiet with a black intercooler behind the stock grille I'm using a Magnaflow in/out same side muffler and 2.5" piping. That's it. No cats, resonators, or anything but turbo's do rid the car of rasp so the choice is yours my friend.