How Many Mufflers Do You Really Need?


August 12, 2005

Glenn

I have a 1972 P1800E which I partially restored starting in '96. Beautiful car, but over time you begin to notice that some parts are impossible to find new. This leaves you with the dilemma of using used parts. In two instances when I have had to replace the steering box (used) and the exhaust manifold (used), they have failed and needed to be replaced (with another used part). You just have to be lucky, I guess. I've heard that you can replace the exhaust manifold with a header, but most Volvo shops I've talked to don't recommend it.

Anyway, here's my question. Does the car really need three mufflers, front, middle and tailpipe? They are always needing adjustment, and the front muffler is rattling something fierce at startup, idle in neutral. I think the muffler is shot. Can I replace the front muffler with a straight pipe? It may be a little louder but, it wouldn't hit the pavement when you go over some driveways, etc.

Thanks

Rich


Rich - If you find that you keep needing to replace a particular part, it would be a good idea to check other parts that interact with the one that is failing. In the case of the steering box, you should check the other steering linkage parts to make sure that they are working properly. If your car's ball joints or steering links are stiff, the steering box will be overworked. Same goes for the exhaust manifold. Check it after dark and see if it is glowing red. If so, you should adjust the fuel mixture and ignition timing until the manifold operates at a lower temperature. Another thing to check would be the exhaust pipe hangers. If you're missing some, especially the one that secures the headpipe to the transmission, the manifold will be stressed. You can see what hangers the car should have by consulting the parts catalog at http://www.gcp.se.

I have never tried running my 1800 without the two mufflers that are standard for the early models, but I have been tempted. With both mufflers, the car is almost too quiet for a sports car. Others have told me that one muffler is enough, and it is not unusual to hear of people replacing the front muffler with a straight pipe. Try it and see. -Glenn.


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