Leland Pate

I'm working on a set of gillet mufflers for another rennlister.
Here's the skinny... I'm doing the old LPMM treatment on them and I've discovered that the two mufflers are not symetrical. So, I've either:

A.) got a bad pair of mufflers (damaged)

B.) got miss matched mufflers (AKA NB and a WB) or

C.) this is the way they are supposed to be.

There is no evidence of damage on either muffler.
The build date stamps do not match but that is not a definate concern
The part numbers don't match, but again, I'd expect them to be different as there is a left and right.

They appear to be perfectly symetrical with the exception of the inlet pipe (from the cat). The right (passenger side) muffler has an inlet pipe that is a bit taller and farther away from the outlet pipe. The only other difference is the location of the mounting tab (see pictures)

I've tried to get into my PET catalog but I can't fix the screen resolution on my laptop so I can't cross reference the part numbers at the house.

Here are the stampings on each muffler:

Left:
993/14-2
993.111.045.11
Gillet 96 03

Right:
993/15-3
993.111.046.12
Gillet 97 01

I didn't notice that the two were different until I had already added the by-pass pipe to the left muffler.

I bought these together from a guy on Pelican parts last year as a back up set. I tried to fit them to my car and ended up with the right exhaust tip not matching up very well... The tip flange kept hitting the cat pipe. Now I think I know why they didn't fit. The right pipe is longer than the left. Now the question is "why".

Can someone tell me what is going on here?
Any input would be appreciated.
Here are a few pics:

JasonAndreas

993-111-046-12 is the muffler that comes with option M159 (engine sound package) which requires a different tail pipe, your left side muffler is just the regular plain-jane version.

Leland Pate

Well, that sucks. Looks like I got shafted. I guess I can't complain. I only paid $150 for them and in 8 or so years, this is the first time I've been bummed about a parts deal. Plus I know many have been burned for MUCH more. Plus, he may not have even known they were mismatched.

I was building a set of LPMM's for Kdurg but I guess I'll have to let him know these are a no go.

Here's my only point of confusion: I thought 993 mufflers were 993 mufflers. I thought people just installed the tips and airbox cover for the motorsound package. I had no idea there were completely different mufflers for those applications. BUMMER!

Thanks for the info, Jason. I appreciate it.

Terry Adams

When Devek installed my Motorsound mufflers recently, they also found that the mounting tab did not line up the same way as the stock Gillett mufflers that I replaced. But they did some workaround and got them on. Of course, the new right side chrome wide oval tip sticks out farther than the left, just like the stock tips that came off.

kdurg

Lee...

Do NOT worry about this. I very much appreciate your time and efforts !! I have Plan B in the works.

Robin 993DX

Both muffler should be identical regardless if it is motor sound or standard muffler. The pipe angle problem is a contribution or shipping damage or result or other damages to the muffler pipe itself.

Even from the factory the two muffler tips sometime don't align, I have seen anywhere from 10mm - 2mm difference between them.

You option right now would be to take another muffler that you know for sure is correct and use it as a reference to see exactly which muffler's pipe angle is incorrect. And then cut the incorrect pipe and weld it back on with the correct angle.

993inNC

Leland, from your pics, the left one (already modified) doesn't look right. The base weld looks a little different as does the diameter of the pipe itself (may just be the pic or the angle). I have a set of 993-111-046-04 and -05's I just got that I could take measurements when I get back in the shop if you'd like.
Are you mig or tig welding those crossovers? or is that some kind of paint?

Leland Pate

Robin, I was hoping you'd chime in as you see more mufflers than almost anyone else on this board.
I agree with your approach. I think I'll take the original pipes off my car and compare them to see which pipe is wrong. I can probably cut and reweld the inlet pipe and make it work.
Again, I am suspicious of the right muffler because it definately did not fit my car when I tried to install it last week.

Chris, measurements would be most helpful if you could take some. Other than the mounting tabs and the inlet pipes, these two are identical. The weirdest part is that it doesn't look like the right muffler is bent or otherwise damaged. It just looks like the inlet pipe is longer and shaped differently.

Keith, don't give up yet...

Robin 993DX

From the pictures it does look like one of the pipe has been cut and welded at the base more than once. (The one that you added the pipe to)

993inNC

okay, it wasn't me.....good. Yeah thats what it looks like. And only looks to be an inch or so different. Probably came off a wreck and they shortened the pipe instead of getting the orientation of the motor in the bay right, or the straightening of the rear end correct.

993inNC

Lee..
Measurement from the top of the can (as you have yours pictured in the first one) to the.....southern most point of the inlet pipe connection is 5" +/- (the cans not flat). Hope that helps.

JasonAndreas

You are probably one of three or four people that have completely dismantled the motorsound and standard mufflers so what are the differences? (there are different part numbers so something has to be different?)

Leland Pate

The internal bypass pipe is larger on the motorsound mufflers.

The next set of mufflers I make I'm going to put the bypass pipe on the inside instead of the outside like the one above. I just got some discs for my cut-off wheel.

viperbob

Think PLASMA CUTTER I want to get one of these just to play with....

Robin 993DX

Here is the picture for the comparison. The by-pass tube is almost an after thought from Porsche, the very early 993 mufflers do not have this by pass tube at all, I believe it was added after so many complaints from Porsche owners that complaint about the sound, and Porsche continued with this approach by adding a large diameter pipe to give more sound, thus the motor sound option.

Interestingly enough 993s headed for Swizerland do not have the by pass tube at all, and also the RS 3.8 muffler does not have this tube either.



A plasma cutter is a must have if you like to cut open stuff, it is amazingly fast, clean and efficient way to cut metal open. Also a TIG welder would be nice too to put them back together nicely. :P