about my 2007 honda si?
 

I have a 07 honda si, i just put on AEM short ram, and bout to get a cat-back exhaust, if i go ahead and change out headers, downpipe, and take out the cat-converter, will i have engine problems if i dont add anything else to the engine. or will i have to keep up grading everything i dont want to do to much except replace the whole exhaust system, and then start on the body work. if someone can help me please let me know, i dont realy know about engines very much.

If your looking to go fast buy a domestic muscle car and save your money.