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off the cuff I think you'd be happy or near it if you dropped the LM1 out and put a basic magnaflow muffler in it's place. clamp down on the drone and the tone shift - and make it tollerable if not sound smooth and clean.

I never liked the sound of any of the LM stuff and my favorites where magnafow and corsa.
magnaflows are the same basic type of muffler, just with a lot more packing.

lm 2 mufflers will be a direct fit.
 

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If you are looking for some cheaper mufflers to weld in place, Jones Maxflow are really similar to magnaflow and are perforated tube stainless mufflers. I swapped those out for the flowmaster knockoffs that were on there and it toned it down while cruising but opened up when it got the beans. Missing my goat already.
 

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Yeah you have essentially opposite ends of the spectrum exhaust systems between your 2 GTO’s. The 2.5” Magnaflow catback is the quietest, whereas the LM1 is nearly equivalent to Spintech in its loudness.

My vote is to live with what you have for now and put your efforts into finding a stock 04 catback. That combination is absolutely perfect for a cruiser, and sounds so good.
 

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Discussion Starter · #25 ·
off the cuff I think you'd be happy or near it if you dropped the LM1 out and put a basic magnaflow muffler in it's place. clamp down on the drone and the tone shift - and make it tollerable if not sound smooth and clean.

I never liked the sound of any of the LM stuff and my favorites where magnafow and corsa.
Not really room for MF mufflers given the way the pipes are bent. I'd have to upgrade to a whole MF system more than likely.

I'm going to try the LM2 mufflers.
 

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I’d love to find a set of 04 stock mufflers in case the JBA mufflers don’t cut it for me.
 

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Discussion Starter · #27 ·
Yeah you have essentially opposite ends of the spectrum exhaust systems between your 2 GTO’s. The 2.5” Magnaflow catback is the quietest, whereas the LM1 is nearly equivalent to Spintech in its loudness.

My vote is to live with what you have for now and put your efforts into finding a stock 04 catback. That combination is absolutely perfect for a cruiser, and sounds so good.
I've been keeping my eyes open for a stock catback ever since I got the car. A nice one with a reasonable price hasn't surfaced yet. But I'd like a fix now as it is almost embarrassing to drive right now in my opinion. If I'm the guy who yells at a guy tearing down my street in a POS Ford pickup with no muffler, I shouldn't consequently be the guy rattling windows as I try to creep my GTO out of the neighborhood. :D

From what Mick and Hubert said above the LM2s should quiet it down a good amount. We shall see. Got a pair of LM2 mufflers on the way from Summit, just a little over $200. I flicked the current resonators/mufflers and they ring hollow so they are NOT mufflers, just hollow. No wonder it sounds like a straight piped menace. I do want to get a few more videos to show what it sounds like at higher revs and from inside the car so I can later post up some comparison videos. Maybe tonight I can get some more video. As I said above, it does sound good, there is just too much sound! Can't even hear the stereo at normal volumes during mild acceleration.
 

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LM2 mufflers are substantially tamer than the LM1 resonators, so those should certainly do the trick if you want quieter.
 

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Anything bigger, longer and/or wider, with more packing in place of those LM1’s will sound much better and quieter. Capt obvious but I hate drone and too much noise too. Even “quiet”magnaflows are loud at wot.
 

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so I was suggesting you get ANY magnflow that would fit - not a GTO part. IE go to a shop that does their weld up and the like and see what they have and can work with to fit into place.

as opposed to internet catalog pieces to fit in your driveway. when I did my GTO and later my G8 I didn't use any off the shelf kit exhaust parts I went to a local place that cut and welded me on a different muffler set or rather cut the resonator out of the stock GTO pipe, removed the stock muff and put in a magnaflow of some model that had the right pipe location to fit well. cost some 600 dollars but worth every penny. Was going to one day have them also fit me different cats but never got to it.

of the G8 I left it mostly alone as I saw no need for changes that impacted the flow.
 

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Discussion Starter · #31 ·
LM2 mufflers are substantially tamer than the LM1 resonators, so those should certainly do the trick if you want quieter.
I hope that's the case. New mufflers should be here early next week. I'll spend the weekend pulling the catback off (again) and trying to get it pulled apart where the mufflers go. It looks to me like this system has been on the car quite a while and it is held together with narrow band clamps so they could be a bear to get apart. Perhaps a little heat and a big rubber mallet will come into play. Anyway, it will be easier to reinstall this time since will be able to do it piece by piece. After the clutch install I reinstalled the catback as one complete unit, that was a bit of fun.

As I mentioned in another thread, after I put on the headers the exhaust tips were no longer centered in the bumper cutout. No idea why since I didn't remove the catback. But, after the guy got done building my mids and installing them, the tips were magically back in the center of the cutout. Hopefully it won't be hard to get them centered again after I swap in the mufflers.
 

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Discussion Starter · #32 ·
Update: Summit shipped the mufflers today, FedEx is saying they will be delivered Saturday. Believe it when I see it, not had much luck with shipped things arriving on time lately. But if they do, perhaps I can have this wrapped up by the end of the weekend. I'll be tearing into the car soon so I never got a chance to get a video of just how obnoxiously loud it is at highway speeds and from inside the car. Oh well, I'll get vids of the new quieter version when I'm done.

Moved the GTO into the shop and drove the Honda for the first time in almost two months. Been a very GTO-y Summer.
 

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To me it is almost deafening. Bordering on obnoxious. I want this car to be a cruiser, don't want it to sound stupid loud. This is about 3 times louder than the long tube, high flow cats, Magnaflow catback system on the 06. That system has no resonators but does have big straight through mufflers out back.
I'm going to agree with you. In it's present form, it sounds like every 3rd Ford Mustang around here. Atrocious.

Then again, I drink from the fine audible wine of having a pair of Magnaflows on my '06, much like you do.
 

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I love obnoxious for a toy vehicle, but know that it’s not for everyone. Ya’ll would hate my GTO.
 

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Discussion Starter · #35 ·
Got the catback off and got the resonators off of the system. Took a bit of tugging and prying but not really a big deal. The new mufflers can be popped right into the system as soon as they show up.
 

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Discussion Starter · #37 ·
I recall when I last had the 06 tuned we did a run with open headers. At mid to high RPMs, the 04 was at least as loud. Also, the 06 with Magnaflow is really loud at higher RPMs. That's what I really like about Magnaflow, they sound great but are a soft rumble in easy everyday driving but absolutely cackle when you give it some throttle. Best of both worlds. The 04 sounded great with the stock mids with cats and resonators, but by going to higher flow cats and bigger pipes with no resonators the 04 was just too much. Hoping the new LM2 mufflers get it more in the range of what the Magnaflow system does on the 06.
 

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You haven’t heard a loud exhaust if you think a 2.5” Magnaflow catback is really loud at higher RPM’s. I’ve had that system on my 05. At no point would I ever call that system loud. It’s as tame as you can get.
 
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Plus one on the glasspacks. I have Corsa's on my 04, and as anyone who has them knows they are loud. My problem was after I gutted the cats, the exhaust picked up a harsh tinny sound. It was bad. The Corsa exits on one side thru a 3" pipe and oval tip. I didn't want to start welding in glasspacks so I decided to try a new tip.

Hooker makes various glasspack tips that are straight thru but louvered inside. I picked a 3x4 x12 tip and clamped it on. It cut the sound by about 25% and stopped all the tinny sound. The piece has nice chrome work. Looks good after 10 years. The car has no resonators.
 
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