Kc's custom exhaust, Bergen county, nj

 

thanks.

 

Don't forget there are two kinds of hacks. Gundo and Fister are different.

 

So which is quieter? What are the differences sound-wise?

 

^^ I would like to know also. Which one of these hacks are more popular and gives the best sound?

 

I can speak for my experience, with a 3.4l . I have the first setup with a 2.5" pipe which simulates PSE setup. I found it a bit too subtle. Nice growl above 4K RPM. I augmented it with a fabspeed CAI setup. The fister set up seems to generate the best sound from what I gather around the forums.

 

So you have the type in the first pic above?

 

The gundo hack IS the same thing as a Fister D muffler. Your first picture is a hack into the same 2nd outlet that the PSE muffler uses and as stated above is generally regarded as being a little more subtle than the gundo/fister. The size of the bypass pipe used for a gundo hack also affects the sound.

 

Yes, done by a local muffler shop. PSE style.

 

Again, the whole purpose of "hacking" your muffler is to bypass a percentage of exhaust from entering the muffler. The first pic isn't really doing that.
A crossover pipe anywhere from 1 1/2" to 2 1/2" is welded in between the intake and outlet and 50% +/- will exit through the outlet without being muffled resulting in sweet loudness!

 

Cross section of muffler. PSE skips a chamber, Fister D has some air bypassing all chambers, therefore it should be louder.

 

Exactly....but a true crossover completely bypasses the muffler.

 

So it looks like most of my questions have been answered - gundo hack won't void my factory warranty, and the gundo hack won't cause me to fail a smog test in CA. I called a few shops around San Jose and decided on one- he knew exactly what I was talking about but I couldn't get an appointment until Tuesday. So I will do it then. In the mean time the window tint and the clear side lenses are done. Only question now is what size pipe for the gundo hack? I'm pretty sure I will go with 2in.

 

How did you establish that the change won't void your factory warranty?

 

Caveat emptor, I am not an attorney, nor is this legal advice, but magnaflow has a pretty good explanation on their webpage why exhaust changes won't void warranties. Basically your warranty would be voided on the mufflers since you modded them, but that's it.
http://www.magnaflow.com/07techtips/faq/question20.asp