Myxalplyx

Went to Meineke earlier to take a look at my stock muffler and decided to change it out immediately. I like the stock exhaust in general but the muffler needed to go. The piping going into the stock muffler is approximately 1.75". The Flo Pro Max muffler I had installed is 2" in and 2" out. I decided to keep the stock exhaust piping diameter reasonable to keep sound levels in check and to not impact exhaust flow velocity too much. After having the Flow Pro Max muffler installed and driving around for a bit, it sounds no different than stock which pretty much shocked me. I mean, NO different.

I'm expecting a small hp/torque gain from this modification. Why? The stock muffler's flow is not straight through. The best way for me to describe it is from my horrible picture that I drew up. Look at this -->

The arrows are an indication of the air flow going through the stock muffler. As I was trying to look through the muffler, the piping did not go straight through. The air flow has to stop, make two 180 turns before coming back out again. It's silly! I've had good results from changing out to a straight through muffler on my cars so I do not see this Fit as being any different.

Here are some pics.
The box the Flo Pro muffler came in.




Stock muffler up top and 2" Flo Pro bottom right



Stock muffler on the Left, 2" Flow Pro on the Right



1.75" Stock Muffler on the left, Flo Pro Max on the Right



Stock muffler inlet. Look closely! Notice the metal at the end of the tunnel?

That is where your exhaust gases will come crashing down at. It needs to make a 180 turn (some going through the small holes) and go into the piping beside it (inside the muffler) before coming back out. This is not smooth flow.

Now look at the Flo Pro Max piping inside.


Notice the light at the end of the tunnel? Your exhaust flow will like this. No restrictive bends or turns to slow down your exhaust velocity. There has to be some gains here, no matter how small.



This is all for now. Just wanted to share. I'm off to work. :D

claymore

Should work well.

JwilhFit15

How does it sound? Does it bolt up directly or did you have to weld it?

Myxalplyx

Had a deep sound to it. I was not a direct bolt-on. It had to be welded. Bisomoto makes a bolt on piece you could add in place of your stock muffler.

evilchargerfan

hey guys, found this thread via a search. wanted to ask, has anyone tried using a 2nd gen exhaust on a 3rd gen fit?

I pulled up diagrams for a 2015+ oem exhaust (18307-T5R-305) and then I did the same for a 2nd gen (18307-TK6-305), looks nearly identical minus 1 heat shield and 1 exhaust tip. I'm thinking, they may be the same and would mean 2015+ owners can run any 2nd gen exhaust

Thoughts?




3rd gen oem exhaust:
https://www.hondapartsguys.com/oem-p...1ob25kYQ%3D%3D

2nd gen oem exhaust:
https://www.hondapartsguys.com/oem-p...BlZWQtbWFudWFs