I have a turbo Civic d16y8 test pipe and 2.5" exhaust all the way back til the muffler. My exhaust system came with a giant fart can but I didn't want it to be too loud so I put the stock muffler back on. How restrictive is it? Will I notice a difference if I switch it?

 

Depends on the power you are at. If i was you I would upgrade to something with a 2.5in inlet. There are aftermarket mufflers that are quiet and not obnoxious. I love my 3in Vibrant muffler. Its quiet, looks great and priced very well.

 

I would think spool up would be the most noticable again depends on your power goals. turbo motors are quieter in general so that fart can may not be as bad as your thinking. .... I have a skunk2 3in in 4in out it is pretty loud just not as bad as NA motor would be

 

Well I swapped the stock muffler for the aftermarket one and you guys were right. The car isn't noticeably louder, and feels bit faster. Thanks!

 

And in both the piping diameter, and how it was bent.

 

I couldn't believe how quiet my rex was after turbo. I have 2.5" all the way back, cut OFF the fartcan muffler entirely and welded a 2.5" pipe in with a tip and it's as quiet as my car was N/A with muffler! I'm running a straight-thru cat and the system has a pretty long resonator, but it sounds good.

 

Yea the turbine wheel acts as a restriction....I think it depends on how big the turbine wheel is but havent looked into it much as far as how noise is related to turbine size.

I would think the smaller turbine housing/wheel size you have the quieter it would be

 

I don't have any feedback as far as FI goes, but NA, stock muffler caused a major restriction and loss of power on a B16A, header/test pipe/2.5 mid/OE muffler.

 

The restriction that you describe is amplified in FI applications.