From Utube single sound bite, in a 997.1, GMG exhaust seems to have a deeper more solid tone than EP1 and CarGraphic. Anyone know if GMG has as good a record as EP1 in not setting off engine lights, no need for flash mod, ease in installation, etc. They're about same in price with GMG unit being much lighter of the two.

 

im heard both the GMG and EP in person and much perfer the EP. the GMG was plain loud whereas the EP was more "musical". The downside to the EP is that its weighs nearly as much as the stock unit. Good luck.

 

I don't own the GMG but have listened to it. I am surprised that your observation is so spot on considering all you've listened to is youtube clips.

Here is my audiophile's review :-): The GMG is among the loudest, most exciting, and deepest sounding exhausts I have heard in the Turbo. The low end rumble is actually quite wonderful, the high end roars spectacularly at WOT - a beautiful thing to listen to. The sound is not continuous like the stock car (hair dryer like), but staccato like, like my Cargraphic and very nice to listen to. If you want the ear drums cleaned, just listen to this thing up close; it's very "race-car" like.

My one and only reservation about the exhaust is its loudness: it is perfect for a weekend warrior, but might be a little loud for daily drivers. I wrote "might" because some people might find it just fine for daily driver. If one wants his inner aggression cleared with every drive, this is the one LOL.

GMG exhaust is another example of how when it comes to exhaust, there is no single "best" sound. Strictly personal preference and you just have to find what's right for you. As for reliability, no problem that I've seen (anyone pls correct as needed), no CEL, and you don't need to tune the ECU with any exhaust (but you might want to - GMG is GIAC dealer and I have to think there is a GIAC file for this exhaust; GMG and GIAC are located very close to each other and I believe GIAC used GMG car to tune, at least in the past).

 

Just like others in this forum, I debated long and hard between the EP1 and the GMG exhausts. Heard and saw each in person. GMG costs a bit less. GMG was also much lighter than stock. EP1 same weight as stock. Both exhausts are hidden, ie, you cannot see them from the rear protruding from the stock bumper. EP1 typically uses the stock tailpipe, GMG usually the paired dual pipes. Although they have a version that is similar to the GT2 that is a paired single pipe that is angled outward that can also be installed in a 997.1.

As Cann described, the GMG is more racecar-like, bit louder, raspier, more burbles and pops when heard from the outside. Inside the car, definitely louder than stock with windows up. Turbo whine more audible with GMG. EP1 is a deeper more refined tone. Turbo whine is also softer. Also comes with the burbles and pops but more muffled. I think Kosmo's description of being musical is spot on. Every 1000 increase in RPM delivers a different sound. EP1 is the same as stock with windows up. The last quality is one of the main reasons I ended up with the EP1. I take the car on long drives and occasionally would like to turn on the radio or talk on the bluetooth. If I want some audio ****, I just open both windows.

Hope this helps. Just like Cann said, exhausts are subjective upgrades just like color. Performance gains are much debated and have varied opinions, especially if you consider the difference between 100 cell (EP1) vs 200 cell (GMG). GMG does offer a before and after dyno. You have to see and hear in person to help you decide between the numerous exhausts out there.

 

Where in Florida are you located? Stop by our shop if you're in the area and take a listen to the Tubi system. You might like it...

 

Appreciate feedback. I guess I need to hear the GMG sound b4 costly swap. My EP1 is loud enough on the outside (great inside), so its not just more noise I'm after, but a different deeper not so hollow-chamber 6cyl-ish sound but more towards deeper more powerful sound of v8s, v10s and v12s. That's what I thought I heard from the GMG soundbite, but maybe that's not the case. I may check with GMG for more definitive sound-bites. I figure porsche turbos have as much or more power than those engines, so why can't we get some of their sweet exh-sound.

 

I tried to find out more about the EP system but didn't have any luck. I ended up with the GMG by listening to the audio clips like you did. I am very happy with my choice. In my opinion there is only a small amount of drone if you keep the rpms around 2500. Other than that it just sounds great. I listen to my radio and talk on bluetooth thru my car with no problems. I think that it sounds great and I am glad I didn't go with a quieter exhaust system. I would make the same decision again.
I just saw your last post. The GMG sounds more like an NA engine than any other exhaust I have heard on the turbo. I wanted something that sounded like a Carrera GT - wishful thinking - but the GMG is close enough.

 

If you already have EP1, I'd keep it, I have had GMG & EP on 3 of my TT(s) and I like the EP symphony best.

 

If you have had both......is the GMG really that much louder at idle and drive away with "cold-start' off?? My EP1 is really too loud with cold start but luckily I found a way to turn it off when starting in garage. With cold-start racket, wife claimed a helicopter had landed in the garage. But if this GMG is still louder even with cold start off, then the change in tone most likely is not worth swapping out.
Appreciate the info......have really considered switching out, but a lot more noise around the house is not a good choice.

 

Cold start with GMG is loud but not overly so. Once it warms up the sound drops down nicely.

 

The GMG is louder at cold-start than the EP, however, both will quite down after 1 min of idling. I'd like retain the stealth look by using the factory tips, however, if you like the quad look, the GMG exhaust does offer that over the EP. I sold my GMG for $2200, the EP will retain its value better.

 

I personally hear a lot of exhaust, and ended up with GMG. It is louder (which I like) than most, but it is the deepest sound out of most of them without the drone. I'm happy with it!

 

I was going to buy the EP for my old Turbo... never got around to it. I really thought that it had the best sound (after going through what seemed like an endless amount of sound clips)

When I bought my new (to me) Turbo it came with a GMG titanium exhaust already installed!

I'm super happy with it... and I'm not a loud exhaust guy....

Now, this exhaust is loud... and will scare children at WOT, etc... but it really does purr.. I thought it was a little much at first.. but then it really grew on me... and now I really enjoy having an exhaust that matches what I'm driving... it's a damn 997 Turbo after all... GTFOuta my way.

 

I love my GMG exhaust. The only con is that it tends to set off sensitive alarms in parking garages.

 

I guess in conclusion, the GMG causes no computer issues just like EP1, that is, no engine lights, prcision install, etc. However, GMG unit has a deeper tone, that is, more like high HP non-turbo engines than does EP1, but EP1 is not as loud (15-25% lower in noise) at start-up (hot engine) and while running at speeds 10-35 mph slowly thru residential neighborhoods. Two other GMG negatives are that turbo teardrop cans cannot be used and GMG is 200 cell vs 100 for EP1. Two big other pluses for the GMG are its lighter titanium wt and lower cost over EP1. If drivers alseady having eperienced both GMG and EP1, if you were to grade on a 1-10 scale with stock being 1 and EP1 a 5.0, then where would GMG be placed -, at a 6 or 7??