[Gregory]

If you know your way around your car, 1/2 hour. If you aren't exactly a master mechanic, could take 2 hours. I've never done a CAI on a celica, but the ones I have done can sometimes be a bitch to put the filter on if you have to put it up through the fender and meet it with the piping. I don't think the brand you choose will make a huge difference because they are mostly the same design.