What's a good exhaust system I can fit myself, including the 2into1 header pipe for my 1973 145e? It had a mufflershop custom on it, but it was about 2.25 inch. I want something more efficient (smaller), I think. I don't care about the exhaust rebreather setup or whatever it was that connected the exhaust back in to the intake. It passed emissions here in Illinois without it. 400ppm HC .08% CO.

Thanks in advance. MP.

You need to remember that your mufflers don't help you pass emissions tests, but cat converters do.

The type of muffler you use is important as diferent styles have different flow capacities and different sound supression charactoristics.

These links are quite useful when looking at customising your exhaust.

Type of muffler comparison

http://www.autospeed.com/A_0381/page1.html

Testing of mufflers

http://www.autospeed.com/A_0382/page1.html

Detailed results

http://www.autospeed.com/A_0383/page1.html

The FI standard system seems to be pretty much what you describe.

I'm not sure I would put the whole lot of mufflers on it.

I've been running one muffler on each car and it sounds fairly

good and not too loud. I just had the shop make me a tailpipe

from the back of the front muffler on out to the rear.

You'll all pardon all my questions I hope, seeing as how I am new to Volvos.

I see that George just described a front muffler and a rear muffler...is that what most Volvos of this generation had? I know my car has one under the passenger side, then the pipe hooks up and over the real axle and into another muffler mounted parallell to the rear of the car.

Would it give any increase in performace, etc, if one were to have a pipe run from the "front" muffler to the rear of the car and simply remove the "rear muffler"?

(This isn't something I'd do immediately, I was just inquiring).

I started doing it because I did mostly short trips and couldn't get

a rear muffler to last more than about 6 months - it never

got hot enough to get dry. I'd guess that there might be a minor

improvement but the Volvo mufflers are pretty straight through,

so it would be really minor, I imagine.

I had only the front muffler on my 1970 145 for about a month or so last summer - great sound, but on long drives it got to be quite bothersome. Even my hard-of-hearing grandfather told me that there was something wrong with my muffler! (Although, I might add, he was sitting in the back seat at the time.)

After putting on the rear muffler, things quieted down considerably with absolutely no recognisable difference in performance (of course, performance levels in my car are all a matter of relativity...)

Cheers!

Ross

Ross, i just removed my front muffler on my 740T...installed 2.5 ID pipe from cat all the way back to a new free flow turbo muffler...sounds great and gain about 10% in HP and quick throttle response....