Hi,

yesterday I finally had the time to install my EVOX bypass on my 2008 GT3. I'm happy with the sound so far, but around 3000rpm I have an annoying cabine resonance. My exhaust is "unplugged".

I'm not sure if this is a general problem when using a bypass or is this caused only from the EVOX bypass, because the tube diamter is bigger compared to Sharkwerks and all the other manufacturer.

Already think about to swith to another bypass

What do you think?

 

let's talk about those welds though

 

I have a GMG bypass sitting in my garage. PM if interested.

 

Here's my experience with 997 GT3 exhausts and drone (resonance):

My previous 2010 GT3 came with an RSS center muffler delete. It did have a bit of a drone at low RPM. Not terrible but noticeable. And I think that's true for all center delete set ups. It's up to the individual to decide how much is acceptable. Some people hate drone, others tolerate it more or less.

My current 2010 RS has the stock mufflers with aftermarket headers & 200 cell cats. Zero drone throughout the rev range. Last year I installed a box that controls the side muffler flappers from the cabin. It's a nifty gadget! With the flappers open at low RPM the sound is much deeper and angry, but there is drone present.

YMMV

 

Thanx guys for your feedback.

@jaundice: I believe the GMG bypass is pretty much the same design as the EVOX bypass, so I think it will make no difference sound- and dronewise. But thanx for your offer.

@ilko: I can controll my flappers with a button in the dashborad. So when they are open, I have a drone around 3000rpm, when I close the flappers there is a minimum drone, not to bad but you can feel and hear it.

I believe the tube size of the EVOX bypass is to big, which is probably responsable for the drone. On the SW or the RSS bypass for example, the tubes are pretty small compared to the EVOX. So this is maybe the difference. Maybe I'm wrong, but that's the only reason I can imagine.

 

No drone with SW bypass.

 

No drone with my Rss either.

I keep hearing that the GMG has a drone and those pipes look like the GMG's except that they reduce in size on exit, which sounds like a recipe for turbulence.

And as NGNG said, that is some sloppy work.

 

+1

 

Sounds is always going to be subjective, but I haven't heard of any drone complaints with our center muffler bypass either.

 

Sent you a message about this in your profile. Thanks.

 

I have the same setup. Fantastic noise when you get on it, but realtivly quite below 3500rpms

Ran it "unplugged" today, and while it sounds great, there is some drone at 3000rpms +\- 300, under load.
It can ger a little tiresome on the freeway.

I am thinking about the remote switch, could make some sense here.

 

I didn't get anything. Tried to PM you but says I can't.
Text me at (214) 502-7784 if interested.

Sorry to hijack thread

 

I have a fabspeed center delete for 500

 

If its too loud unplugged why not plug the valves back in for roadtrips etc and unplug for track use or weekend drives ?

 

On my RSS setup I actually removed one of the vacuum hoses from the valve, but left the other intact. It's an in-between for having the sport button unplugged since you still have one valve functioning. And if you want it a tad louder you can always activate the sport button which will open the other valve.