Muffler Replacement
"Huh? What? I still didn't hear you."

by Mike C.   Technical Index
     That's probably what you've been saying to the person next to you while driving your VW lately, especially if you haven't been paying attention to your exhaust system.  No, air-cooled VWs aren't the quietest engines in the world, but they are very bearable when the mufflers and tips are in good condition and the seals between the
muffler and heat exchangers aren't leaking.  Also, a bad muffler or tips can hurt performance since they won't let the exhaust gases escape the way it was meant to be.  This article will deal with replacing your old muffler and tips.  I wouldn't bother reusing your tips unless you had just put them on the week before.  Those chrome tips are el-cheapo (around $2 each) and the chrome is probably worn off the old ones anyhow.  Also, don't attempt to reuse the muffler clamps unless they are almost new, as they will most certainly be solid rust otherwise.
     Here is a list of the things you will need: 
     Chrome tailpipe tips
     4 Exhaust clamps
     2 cylinder head-to-muffler gaskets
     4 donut-type seals (2 for heat exchanger
           connections and two for the tips)
On the muffler and related parts, J.C. Whitney sells the entire kit with all the stuff listed above, as well as most other mail-order places that carry VW parts. If you can get German-made muffler clamps, I highly recommend them, for they are much more durable and last much longer than the cheap "Canadian kits" that you get most of the time.  As far as whether to get German or Brazilian mufflers, take your pick unless you are going for strict detail.  The German-made tailpipe tips will not whistle when new, nor did they ever when the cars were new.  So if you want that kind of attention to detail, go for it.  There is even a stainless steel version of the stock muffler, down to the tailpipe tips and clamps.  Expensive, but may be worth it to you.
You will need a standard screwdriver, 13mm combination wrench, 10mm combination wrench, 10mm socket and " drive ratchet, a small pair of ViseGrip pliers, hammer, antiseize, four copper exhaust nuts or stainless steel nuts that fit the studs on the cylinder heads, and some penetrating oil.

1.) Remove the two fresh air hoses going to the rear engine tin.
2.) Remove the rear engine tin.  This will make it easier to get to the upper exhaust nuts and is required to access the heat riser bolts. 
3.) Spray all the exhaust nuts with the penetrating oil and let it sit for a few hours or overnight if needed. 
4.) Undo the clamps at the heat exchangers with the 10mm wrench and ViseGrips. 
5.) Take the 13mm wrench and undo the flange nuts at the cylinder heads. 
6.) Undo the bolts at the heat risers with the 10mm socket. 
7.) You'll probably need the hammer to shock the muffler loose so it will slide off.  It'll come off with a little persuasion.
8.) Clean off all the gasket surfaces.  Be careful cleaning the exhaust gasket off the aluminum heads, since the aluminum will easily gouge.  You may want to take a strip of emery cloth and run it around the heat exchanger connections to make sure they are clean. 
9.) Slide each exhaust gasket on the heads and two of the donuts on the heat exchanger.
10.) Position the new muffler loosely on the heads and exchangers.  Loosely, I say, because you want to have enough breathing room to slide the new gaskets between the heat riser tubes and muffler.  Do this first and then,
11.) Tighten the heat riser bolts down.  If you bolt the muffler on the engine first, it may be difficult to get the heat riser connections made. 
12.) After you have the heat riser tubes on and tight, snug the exhaust head nuts down using the copper exhaust nuts. 
13.) Put one clamp assembly on each heat exchanger connection and tighten the clamps down evenly on both sides. 
14.) Go ahead and put the rear engine tin back on and then the fresh air hoses, replacing any torn hoses as needed.
15.) The tailpipe tips will be the final step.  Depending on the year of your VW, you have to know how deep the tips need to go into the muffler.  This sets the correct backpressure for the engine you are running.  I do know for a fact, the correct tailpipe position for '73 and '74 models is all the way in.  The earlier models are installed at different lengths, measured from the tailpipe flange to the end of the tip.  Make sure to see a shop manual for these, as I am not familiar with all the different ones. 
16.) After sliding the tips on in their correct position, slide a donut on each tip, then install a clamp on each, tightening both evenly. 
     You are now muffled!
If you are installing one of those header/muffler combinations, the header goes on very similarly to the stock muffler.  The muffler for the header is usually held on by three bolts/nuts that attach to the header collector in the middle.  I will tell you that the header is a worthwhile add-on that gives more power, torque, and better mileage.  I ran one on my '74 and loved the results.  If you want to paint or have the mufflers or headers coated, do all this before you install it for the first time.  That way, you only do the job once.  Now go cruise the roads and be able to talk to your wife, in-laws, buddy, girlfriend, or whatever, on the way to get that delicious bratwurst burger!