I am thinking of enlarging all the piping to 2.5 inch and getting a magnaflow exaust. Also I am going to switch out the resinator. I got a estimate for 250-300 bucks. is this a good deal?

You don't need 2.5", brother...save your money for something else. You can go with the Magnaflow as it sounds great, but forget about the piping. The gains are insignificant.

Your car is VERY shiny...I like it. About your engine, post pics of it. If your car does not say GT, it is an ST. Mine came with all the GT options also, except sunroof and wheels. I was in your same boat...didn't know if it was an ST or GT so I looked in the engine bay. It said 7A-FE so I knew it was an ST. If you have a GT, your intake manifold will say 2.2 and the engine is aiming kind of backwards. The ST engine is upwards completely.

The 7AFE simply doesn't produce the volume of exhaust gases to justify 2.5" piping. In fact, it doesn't produce enough to justify 2.25" -- 2" is plenty for that small a motor.

You can improve flow, but increasing the size of the piping isn't the way to do it. The larger you make it, the less efficient the system will be at getting rid of smaller amounts of exhaust, such as those generated at low- to mid-range RPMs where most of your acceleration comes from. A big exhaust pipe will actually create backpressure by allowing the small amount of exhaust gas to expand to fill the larger space, which means the gas cools off and slows down, acting like a logjam to gas exiting the engine.

As for the resonator -- don't. The stock resonator -- which is not a glasspack, and bears a resemblance only on the outside -- is not a significant impediment to exhaust flow, especially on an ST. There's not really enough flow to impair.

The muffler can indeed be improved by using a straight-through design, which is essentially a perforated pipe wrapped in acoustic absorbtive material. MagnaFlow makes some excellent designs that will fit the stock location. Please skip the 10", 6" round fart cannon. You should be able to get the new muffler for $50-60. Welding it would cost rather less.

[FONT=Arial]-OOBE+Jun 23, 2005 - 7:50 PM

I know for sure that my engine is the 7afe model. I was just seeing what everyones opinion was. I already got a Weapon R secret Weapon intake. It sounds great and boosted my gas mileage by about 2-3 mpg.

thx Galcobar for the info. Now I will be able to save $150 bucks or so. your comment was very usefull.