An idea for exhaust....

I was sitting in bed last night and i know a cuple people have mentioned this before. but would we even get a power increase if we kept our racing beat muffler and make the exhaust from the cat to the muffler 2.25 inches. since the racing beat mufflers inlet is 2 inches wouldnt that negate and pipe increase since it isnt increasing flow, its just increasing more area in a cretain part?
but im no expert on exhaust.
can anyone help me out on this.

there was an interesting article in a recent sport compact car magazine about aftermarket exhaust. while large bore exhausts are nice, and they do improve on the flow, what you want is velocity to extract teh gasses out of the engine. with a large bore system, you get good flow, but low velocity and not good performance. with a well thought out system, you can get more power and not be much louder than stock. with a good muffler, you can have good flow and good sound deadening effects. of course, if you want loud, go for it! i was thinking of having a system made, out of 2" mandrel bent tubing with a Borla muffler. i just have to find the right style tip.

If you want an "Engineered Cat-Back System" You should go with Bosal. They have dyno'ed the set up for the Protege package. Atleast they say they have and that they will post slips soon. I believe them and the people who have the systems seemed to be very pleased with them.
Just my 2cents

would just having the resonator removed help in hp? or would it be useless. im not going to spend 300 some odd dollars on a new exhaust system when we already have a bad ass one on ours . i just want to better my already great car. i want to keep my racing beat muffler now. but i want it to sound more scary. our exhayst seems a little toned down compared to some factory sport exhaust. i would like better sounds and better performance.

Buying a different exhaust manifold or "headers" is the best way to increase the velocity of the gases exiting you engine. That's why there are different designed headers. Larger exhaust piping helps of course, but like Nik said you will lose torque on the lower end. Perfect example are the headers designed for the Honda's.

Take a look at DC, APEXi and MUGEN. DC's most popular header is their 4-2-1, uses more good bends, but seems to taper off slighty at the collector. This is good for mid range torque, but doesn't help a whole lot on the top end where honda have most of their power. MUGEN uses a 4-1 design that has larger diameter piping, very few bends, and a large collector. The MUGEN 4-1 header is the best for top end power, but the comes with the sacrifice of the low and mid range torque. APEXi uses the 4-2-1 design which by far is the best for overall HP gains. Further more the the ports and bend are deburred and hand ported for optimal exhaust flow. APEX also uses slightly longer piping before they make the final bend to the collector which mean more midrange torque, with out sacraficing the top end.

Although we only have one or 2 headers to choose from with our MP3's, the market will develop and we will eventually see more. Has anyone looked into SR-Motorsports? They have an exhuast for the MP3 and P5. I will call them to see if the have one in their showroom so I can see it in person. I guess it all comes down to what kind of power you want. Mid range torque or peak HP. I'm more into torque.