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Gutted my mufflers and hey, not bad!

6387 Views 34 Replies 17 Participants Last post by  mprest99
My wife and I spent the weekend looking for a new toy car. I orginally wanted a Z06 the cadillac dealer had used, but then started thinking elise for something totally different. The wife obviously was not interested and it looked like idea was dead until I told her to pick the new toy.

After looking at many two seaters the one she liked the best was a used sl55 AMG! Lucky me. When I test drove it one thing that struck me the was what a great low exhaust tone it had. I decided to replace the exhaust on the V, but since it was decided I thought why not try the gutting the muffler mod I saw on this forum, if it failed I would just replace it with a new one.

After I took out about 3/4 of the fiberglass in both muffler the sound was really good. I did one at a time to see if I could tell a difference between the stocker and modified and there was a significant improvement. Not any louder, but alot more bass you can hear and feel at idle and low rpms. Very close to the AMG. Saved a grand at least for now.
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do the magnaflows have any packing in the mufflers or x pipe???
Where's the I Told You So emoticon?


Dunno, from the sound clips available on the internet, the magnaflow would have been my first aftermarket choice given how low the sound seems. I really didn't want a much louder system though.

Seems like a lot of work in sound reduction is done at the cats and resonator in this car.
I've found the combo of RT cats and gutted stock mufflers to be perfect (after having many versions of the BB exhaust, with and without headers/cats).

If the V stays in the stable, she's getting cutouts.

Yeah thanks. I definitely got the idea from WW posts. Did it like you suggested by dropping the exhaust, cutting a 1.5 inch circle, pulling the fiberglass, and replacing with a sink hole cover. Was skeptical about how much it would change the sound, but there was definitely a difference when I compared the gutted side to the ungutted. My neighbor came over and probably thought I had gone crazy, although he is a closet ricer at heart.
Don't thank me - I borrowed the idea from elsewhere.

He said *closet ricer* :canttalk:

I agree, with the WW video I saw a while back I've been wanting to do the same mod as it has the sound of letting people know it's not a regular Caddy...but it maintains a higher sound quality.
I promised myself I would do a before and after sound clip, but didn't get a before. I'll work on the after.
is there a "how to" on how to gut the mufflers?
i second that emotion...
If you search gutting mufflers you will see the how to by wildwhl. Super easy. Just drop the exhaust, open a 1.25 or 1.5 inch hole in the top and fish out the stand of fiberglass that is inside. Then plug with high temp copper gasket sealer and one of those sink drain hole covers of the appropriate size.

Athough this is reversible theoretically, I'm not entirely comfortable telling people to gut a set of expensive mufflers. The change is subtle, but perfect for what I wanted, but I was prepared to order an aftermarket if I didn't like it.

I have the sound clips recorded, but have to download them tommorrow at work and post.
Ok, I have a sound clip, but cannot post it. It is a mp3. I can send it to anyone interested to post for me.
i'd like to get ahold of that sound clip. i can upload it on youtube if you want me to.
about how long does the gutting process take? i'm trying to schedule some time to do this and the wheelhop washer mod
It took me a half hour to drop the exhaust and twenty minutes each muffler. Another ten to rehang the exhaust. I could drop the exhaust again in fifteen minutes however. Also I had a terrible drill (I think it was really only for wood). You could save time by drilling the side or bottom, but not if you want to avoid possible warranty issues.

I sent the sound clip to your email by the way. All of the these exhaust clips seem a little distorted and this one is no exception, but the point is there.
I uploaded the clip to youtube. feel free to check out my other vids also.
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