I was wondering which exhaust hack is this - see the attached for reference. It is obvious that the added part was too close to the bottom of the bumper and attachment screw. No idea when this mod was done or where.

 

Looks like someone may have tried a Gundo hack, but I cannot tell where that tube goes.

 

As stated above, hard to tell without knowing where that pipe leads, yet, like a puzzle, I’m trying to figure this out 🤓.

Pic attached for reference only, pls disregard the arrows.

 

That would be my guess, too. Maybe the tube simply empties into the open air inside of the bumper cover instead of connecting right before the exhaust tip?

@sportlineguy, can you get a pic of where that added tube terminates? Or, if you can't get your phone up there for a pic, just have a look and tell us?

Apparently, there are 2 styles of the hack:

One where there is a connection between the inlet and outlet pipes:


And one where you connect to a capped hole in the box:

I don't know which is the preferred method or why.

 

Let me see if I can get some better pics - I don't have access to a lift right now. Appreciate all the help on this

 

Options without a lift:

- Handheld mirror
- Telescoping mirror if you happen to have one in your toolbox.
- Recording a cell phone video and sliding the phone in there. Then review the video after you pull it back down. I used this method to confirm that my frunk light was indeed turning off when closed 😅

Jacking up one corner would help all of the above.

 

Looks like someone tried to improvise with the hack

 

I juyst looked but was unable to take a picture because of the angle and space available. It looks like a short tube connecting the inlet and outlet of the pipes. Not too bad when cruising but a bit louder than stock when accelerating hard. Guess that was the cheaper fix to modify the exhaust back in the day vs a proper exhaust upgrade. Will live with it a bit longer than explore other options.

 

You’re describing a Fister modification. It’s pretty well regarded.

https://fdmotorsports.net/shop/ols/categories/996

 

This has been wrong many times, the first picture is the Fister mod. the second picture is the Gundo mod

One where there is a connection between the inlet and outlet pipes is the Fister mod.


And one where you connect to a capped hole in the box is the Gundo mod.

 

Whats the effective difference?

 

That is the right question - is it just a bit 'louder" or does it actually add anything?

 

Mine has the Fister mod and I like the growl it adds in the higher revs

 

Thanks for the clarification! This helps me a lot as well as I'm considering one of these mods.

Are you familiar with the pros/cons of each or is there a thread somewhere?

 

Thanks for clarifying the difference between the Fister and the Gundo mods. I’ve always thought they were the same thing, until now.

Here is a diagram of the muffler’s internals.



The Fister mod completely bypasses the muffler, but the entry into the muffler isn’t sealed off either. So I’m guessing at high revs, the exhaust will seek the area of lowest resistance and largely exit through the bypass pipe. At low revs, the exhaust may travel through the muffler (as well as the bypass pipe) since the resistance through it is fairly low.

I would guess that the noise is pretty tame until the RPMs get high.

As for the Gundo, the pipe only bypasses the final stage of the muffler. Because all the exhaust must enter the muffler and go through the initial stage of muffling, I suppose this will produce a more mellow sound compared to the Fister at all rev ranges.

I found this diagram via this link:
https://rennlist.com/forums/996-foru...6-muffler.html