Hmmm... "Civic", "10 second car", sounds like someone has been watching the Fast and the Furious and is furious about the imports taking over the streets.
Well, I have bad news. You won't go into the 10 second club with an Intrepid. Probably not even with $25,000. You could make a tube chassis and put on the Intrepid body, that makes the most sense to me. Basically, if you want to run a street car in the 10's you are going to have to sacrifice everything that today's modern car has. Your car is going to have to be devoted to going fast. There will be no nice radio or auto climate controls or rear seat even. To make this type of commitment with an Intrepid is nuts. That isn't what our cars are meant for.
I do believe you can make it quicker than it currently is by doing a lot of work on your own. Follow one of these guys' directions on making an intake kit and freeing up the exhaust as well.
It will cost money as there is no aftermarket for the Intrepid. My advice is if you are really serious about running 10's, buy a car that is capable of doing it. There are many cars out there with an aftermarket supply of parts. The engineering, design, testing, marketing and everything has already been taken care of. Of course, you could try do develop an aftermarket for our cars but I'd prepare to take a bath and get dry shaved!
