Anyone have a picture of what the inside of the stock 99 muffler looks like? Thinking about modifying one, but dont want to cut it open until I know whats in there. I saw a post where a guy cut a hole in one end, drilled out a couple of the baffles then welded it all back up, but cant find it now.
Well, I got everything welded back up today and bolted it back up to the car tonight. And to my surprise, it is VERY close to stock sound. Hard to believe with the glass packing removed and the hole in the pipe inside. Back to the drawing board.
May try an old trick I did on the Mustang I used to have. Thinking about puting a hole in the bottom of the muffler in the same chamber that the pipe I cut the elongated hole in the pipe, and weld in a short piece of pipe (2-3" long) so it is like having a turn down as well as running out the back. On a flowmaster, you would just cut a hole in the back of the muffler and weld in a turn down. I don't want to cut a big window in it again and I think this may give a decent sound, since the gases will still have to run through a couple baffles before the dump. Some flat black paint on the muffler should help hide it a bit too. I know this is Jimmy Rigged all to hell, but I still have the stocker to throw back on if this sucks completely
Drilled the holes and put in the mini exhaust pipes and it still doesnt have the sound I want. Cut the thing back open today. Gonna cut some of the baffles out of the way and start from scratch. Probably run a piece of perforated pipe the whole way and repack it.
Looks like 5-chamber, mostly acoustic cancellation, with some packing in one chamber. We don't get a good look at the 1st chamber, but looks like a solid (non-preforated) pipe there.
Looks to be some kind of Helmholtz Resonator running through chambers 3-4-5.
The soot pattern in the packed (2nd) chamber seems to indicate there is lots ... possibly more than necessary ... packing in there. Is this chamber open somehow to the first one?
Not the worst OEM muffler I've seen.
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