seymour44 said:
the '04 injen cai fits and cosmo makes a cai for xrs too. k&n have a sri for the t-sport that will also fit. celica intake do not fit, completely different intake set up. with regards to headers - dynos have proven that there are no after market prducts available that make power over stock.
head to
www.9th gen corolla.com for more info on our cars.
You're right about the headers, DC sports tried to make one for the celica and it actually caused a loss in power.
The great thing about the XRS exaust stock is that it is already 2" diameter, which is big enough for our 1.8L motor. All you need to do is get a less restrictive muffler spliced onto your stock midpipe and you will be good to go. I really noticed the difference when I had my flowmaster exaust installed. It pulled harder throughout the whole rev range. By the way I paid $150 for mine. The only issue with a new exaust is our body kit, it makes it hard to stick a muffler on and have it stick out the back. My solution was to have them put the new muffler on, hide it behind the body kit, and put a small turned down tip on it. I really did not want a big old lame shiny chrome tip sticking out my car's ass anyway. If you do have to have your muffler visible to the world, it is going to be really really close to the ground, so be careful.
Unless you go with the overpriced TRD/borla axle back, which has this little flacid pipe dangling down and back from the muffler, which looks absolutely rediculous.
Oh and don't believe claims of a "cat back" for the XRS, there is a hose running into our exaust way back by the rear axle, so anything that says "catback" is actually an axle back, which is no better than just splicing a muffler on.
I would recommend either a flowmaster flat muffler, or a magnaflow oval type. They fit really nicely on our stock system, and sound great, and make a big difference.
Good luck! And be sure to research this, exaust is not something to rush.
Oh yeah, and your car will sound like a friggin monster with the CAI, I almost had an accident in my pants the first time I hit lift

I rarely break 4K rpms now, I have so much low end power.
edited to add: my flowmaster is the 40 series, it's not buzzy or ricey, just really really deep. I love long trips, listening to my music until I accelerate, it sounds like a high reving muscle car.