tech: cheapass muffler hangers

[treed2@u.washington.edu (T. Reed)]

After living with my crappy-excuse-for-a-muffler since I bought the car,
last summer I purchased a $35 Dynomax Superturbo to replace the stock 16v
muffler. After calling 5 or 6 muffler shops in the area I ended up putting
the whole project off because I wasn't willing to pay the bastards $60 to
weld hangers on the new muffler.

Well, yesterday completely on a whim I decided to get under the car and
pull the muffler off to compare it side by side with the new muffler. The
clamp was so rusted that it came apart in my hand, and when I got the
muffler out and stood it up on its end, two fistfuls of rust came out of
the inside. Nasty.

As I looked at the two mufflers together I came up with this great idea..
if I could find another VW-style exhaust clamp (the C-shaped type with a
single bolt, rather than the U with two nuts on it), I could cut a section
of steel rod to length, slip it through the clamp (after removing the
bolt) and then bend it so that the ends would be in the stock location and
I could slip them in to the rubber hangers. For the rear hanger, I could
just use a very long bolt on another clamp and put the end of the bolt
though the rubber hanger, maybe with two nuts and a washer.

I also had to deal with the problem of the 16v exhaust being 2 1/8"
(50mm?) and the muffler being 2 1/4".

I went to an auto parts store first and got an exhaust adapter for $1.49
which I intended to use as a shim, and a $4 tailpipe that was 18" long
(when I first put it on it stuck out about a foot further than the
bumper). Couldn't find any C-shaped exhaust clamps, though.

Then I went to the hardware store and got a 3' section of 3/8" diameter
steel rod ($3.05), a 6" long bolt with 2 nuts and 2 washers ($1.06). Since
I didn't find the clamps earlier, I bought 3 feet of flat 1/8" thick steel
about 7/8" wide ($2.82).

I made the rear hanger first. I used my superman strength to bend 8 inches
or so of the flat steel in to a clamp shape then drilled a nice hole
through the top. Stuck a bolt through it, put a nut on the end of that and
put some heat shrink on the remainder to protect the rubber hanger from
the sharp threads.

For the front hanger (that spans between the two rubber thingies), I made
another clamp-shape out of the flat steel and drilled a 3/8" hole through
the top. Then I laid a 14" section of steel rod between two 2x4s and gave
the middle a light smack with a sledge hammer to dent it a bit. I also
bent the outer 4" on each side so they would be in line with each other.
Then, I slipped the rod through the clamp shaped piece of flat steel and
the hangers were ready to test.

Here's a pic:	(note: not the final incarnation..)

http://students.washington.edu/~treed2/hangers.jpg

After an hour or so of trying to get the shim on, then trying to get it
off, I finally ended up cutting the shim tube lengthwise to form a "C".
That was the only way I could get both the shim to fit inside the muffler,
and the midpipe to fit inside the shim. It leaks a very small amount.. but
not enough to really be audible and it does the trick.

The test-fit revealed that I needed a bigger "dent" in the middle of the
rod for the front hanger, and I also needed something to pinch the clamp
for the front hanger together. So I hit the rod with the sledge
again and drilled a small hole in the clamp so I could put a nut and bolt
through it.

When I tried it on after that it sat perfectly.. the midpipe was no longer
resting on the rear axle and the potential for severe rattling from the
front clamp was gone. I did pull the rear hanger off to cut down the
length of the bolt, though.

I've put 15 miles on the new muffler so far and while I can't get used to
the car being so quiet, I'm confident that the setup will hold up for
at least the life of the muffler. I can grab the muffler from beneath and
shake the hell out of it and nothing moves - its all on there solid and
the materials are definitely of adequate strength.

Total cost: $12.89 including the tailpipe

(maybe if I left all 18" on, I could start a new fad.. long exhaust tips
instead of large diameter? bah.. too late, I cut the excess off earlier
today)

Cheers,

-Toby

--
'87 16v