Just picked up my 08 civic Si 4dr.. I was looking @ the HFP Si muffler and looks pretty much the same as the Si muffler on my car now, but DOES NOT have the black inner piece inside of it. My Question is, is there any way I can just take the Black inner piece out of my muffler?

 

They're not the same. The plastic is filler for the OEM pipe, while the steel tip is just a garnish. The diameter of the exit of the HFP is larger than that of the Si's.

 

For a little more money, you can get a good full cat-back system.

 

Thanks for the info K5^