Poor Man's GMMG
 

Okay, what do you guys think about this. Just an idea I'm throwing around. I currently have a Hooker Catback, so the I-pipe and OTA pipe are gonna stay just like they are. I'd like to weld a flange to a Magnaflow merge y-pipe and bolt it up to the over the axle pipe and do this...

Magnaflow y merge 25.99
Sweet Thunder Mufflers $100 pair
Assorted 3" tubing (2 90 deg bends and 1 180 deg bend plus straight pipe) ~$30

Poor Man's GMMG <$200

Sounds complicated to me but if it works and sounds good then....hey, why not!

"looks" exactly like gmmg. Should be interesting. Try it and let us know. Good luck

I think the biggest hurdle will be getting the mufflers and the merge collector fitted under the car in the limited space. Can you get a custom length sweet thunder? If so that may solve that problem. Looks like it could work if you can stuff all that in that area. Keep us posted.

I did this over a year ago.
Bought all the mandrel SS bends and 2 SS sweet thunder mufflers. It sounded ok, I also had a bullet in the I-pipe. Still rasped, but did sound very deep and was pretty loud.
http://memimage.cardomain.net/member...76_15_full.jpg

We made the mistake of not making it exactly like the GMMG, they route the drivers side pipe with the shorter piping for a reason. My passenger side exit pipe was very short and looked a little odd. Changing the pipes from side to side like I did also sets the mufflers and pipes too far back IMO.
That system was spliced into a loud mouth cat back, so what your proposing can be done.

I know have a Hooker catback which rasps less than that setup and I plan to add a flowmaster y-collector and Borla muffler back into the I-pipe for a cleaner sound.

Personaly, I never understood the gmmg system. Why have two mufflers in a y-pipe non-true dual exhaust system. If I were you I would lose one muffler, put the remainding muffler in the I-pipe, cut your exhaust after it goes over the axle and weld your magnaflow-y on and exit the bumper with two pipes. Basicly would be the same thing if you had a loud mouth and welded a sweet thunder in place of there resonator.

Actually, I seriously considered welding a sweet thunder into the i-pipe of my loudmouth. The only problem was that the sweet thunders only come in 2.5" ID. That, combined with the fact that the mufflers are baffled to begin with, meant I would have a serious bottleneck in my exhaust.

FAST LS1: That is exactly what I was planning, but I was hoping I could get a much closer radius 180 deg bend than what you have. That should make things a little more compact.

DWillTA: Yes, you can get the sweet thunders in custom length. I'm gonna take exact measurements tomorrow and try to plan it out.

The only worry I have is my ORY. Don't want to much rasp which I know I will get with this setup. I don't know if a Borla in the I-pipe will help, or if I sould just pick up a Kook's catted y. I'm happy with my current setup, just wanted to change to a more aggressive sound (not as aggressive as true duals though, been there and done that).

Keep the suggestions coming.

I think you may have a problem since the flowmaster merge collector is something like 10" long, you're not going to have much room for the chambered sections.

No, it's not a flowmaster merge collector. It's a magnaflow y section. I don't think it's much more than 8" in length, and it's a slip fit.

they sell 3'' id mufflers, just the inside baffel is 2 1/2'' inside of the body. people run them all the time on true dual setups. Actually texas speeds version of the loud mouth the rumbler is going to be available w/a sweet thunder in place of the old bullet.

Running 2 mufflers, even on a y-pipe produces a different and sometimes more pleasing tonal effect because no 2 mufflers sound exactly the same, so you get a pseudo-stereo effect especially when the length of tubing is different prior/after each muffler. The sound is also affected by how much of the exhaust gas is going through how big of a muffler and things like that.

That's cool, definately makes sense. Doesn't it restrict/ cut down on flow,having two.

if you take a 3 inch over-axle pipe and split it into two 2.5 inch pipes... the total cross-sectional area goes from 6.8 sq. inches to 9.4 sq. inches. So as long as you don't bottleneck it down with a press bend or something and as long as you use no-loss mufflers (see JRP's sticky) the 2-muffler split shouldn't be a performance concern except that it may weigh a little more and cost a little more (which means less $ for something else)

Don't be misled... 2 mufflers will sound different than 1 muffler on a y-pipe system... don't expect it to sound like a true dual system though!

Cool, thats good to know :cheers: