sullivas

Thinking abt doing the hack on my 2005 C2 with 1 1/2" pipe, not too aggressive but a little more sportier sound. I'm wondering if there is a problem with heat buildup considering it seems that the hack pipe would shoot hot cat exhaust directly at a small area on the side of the OE 'out' pipe it is welded to. Experiences/advice welcome. Thanks

vern1

Go with the 2" pipe. I would hardly call it too aggressive and its a deeper sound. Regardless, assuming they use SS I cant imagine there would ever be any problem. At least never seen any issues on mine

But be careful, its not a full PSE sytem. so not Porsche approved so be prepared for the condescending comments.......

ajayabb

Just did the 2" hack on my C2. Best mod for the money. Great sound yet not obnoxious. Sounds exactly like PSE. No regrets whatsoever.

Matt(inMA)

did my '06 in '07 with 2" pipe and have been extremely happy! Not too loud nor too quiet and NO interior droaning. Check here ->

David in Talent

I did the 1 1/2" pipe and am VERY happy with it. A friend on my recommendation did this mod also and thought that the sound was not loud enough for him. We all have a different ear for sound so you might want to listen to examples before you jump. Reason I did the 1 1/2" mod was that if I did not like it, I could always enlarge it to the 2" pipe. Whatever you do, be sure they use STAINLESS STEEL by-pass piping.

dak911

Pretty sure this will void the CPO, (06 S 17 months remaining), warranty, correct?

Skibum

Only the muffler warranty. The engine and car's warranty remain.
Before you cut, remember there may be a time when you want to return everything to stock.

PTParks

I went with a 2" pipe. My only complaint is that I waited so long to have this mod done. Great sound ( I also have the AWE crossover pipes which eliminate the '09+ center muffler) and absolutely no interior drone. The mod adds a lot of "body" to the exhaust tone and is evident thoughtout the entire RPM range. This is how the 911 should sound like from the factory.

mjsporsche

Can someone explain the difference between the FD Motorsports mufflers and the Gundo Hack. Looks like the concept is the same but the quality of the Fister product with the added pipe looks top notch.

http://www.fdmotorsports.net/index_files/Page732.htm

PTParks

Exactly the same concept.

Fister products are top notch, to be sure. However I got my GH done much cheaper and definitely saved time doing it locally vice mailing in core mufflers to Fister and waiting for their modified mufflers to finally arrive back home. The muffler shop I went to even shaped the ends of connector pipe on a grinder to fit the curve of the inlet/outlet pipes on the muffler. The welding was clean and solid.

Skibum

Fister is the Cadillac of this hack.
Before you cut.. have you heard one in real life?

sullivas

No, just before's and after's on the Fister web site. Do you think the volume increase is that significant?

PTParks

Well, it's not stock, but it isn't open headers loud either. It has been compared to the Porsche Sport Exhaust (PSE).

Skibum

Sound is far too personal a thing to make what I think even close to credible.
It is way more than just volume, it's timbre, rumble, burble, tone....

With this mod you are essentially bypassing the mufflers for a certain percentage of exhaust gas.
This is not what the Sport Exhaust does. (It always passes gas through the muffler)

My personal feeling and no one jump all over me for it... is that it's a bit too harsh. Like you would expect an open exhaust to sound (but not as loud).

PTParks

I respectfully disagree. The hack results in a sound that is unobtrusive at idle with just a slight increase in volume. Parked in my garage the cold start is louder because of the car retarding timing and cold start fuel mixture than it is a few minutes later when the car has warmed up a bit. That aspect is no different than before the hack was done. On acceleration the sound is deeper, maybe just a tad louder, but not raspy, monotone, or "fart can" loud. Of course the farther you push the go pedal the more volume you obtain. On downshifts there is (at least on my car) a slight exhaust burble heard initially but it's not reminicent of some 60's era muscle car. There is absolutely no interior drone or panels buzzing at different RPMs like you can have with other more aggressive sounding exhaust systems. At a steady state cruise at highway speeds you can easily listen to the radio or carry on a conversation with the passenger.

As I previously stated in an earlier post, I have the AWE crossover pipes installed which you would think would add a significant amount of volume to the exhaust sound. By themselves the crossover pipes did very little to the exhaust note, and was only noticeable on initial take-off (which tells me the center muffler on '09+ models doesn't do much muffling). Combined with the hack, I have, IMHO, the sport (sounding) exhaust note I was looking for. Other 911 owners have ridden in my car and have commented very postively on the sound. Not saying there isn't one out there, but I have yet to read about someone who did the hack that wasn't happy with the results.