My custom exhaust setup.

[Balleristic31]

yea the stock one had a couple holes rusted through it so it sounded pretty.... interesting haha

i believe the dynomax is NOT straight through and has a curved path.
but dont quote me on that cause im not positive.

[91 318is]

yea the stock one had a couple holes rusted through it so it sounded pretty.... interesting haha

i believe the dynomax is NOT straight through and has a curved path.
but dont quote me on that cause im not positive.

Hmm, I mean with the thermal research, you can see right thru it.

We'll see what happens. I think advance auto has some dynomax super turbo's up there so I have that option if need be.

[trackjunkie21]

Hmm, I mean with the thermal research, you can see right thru it.

We'll see what happens. I think advance auto has some dynomax super turbo's up there so I have that option if need be.

How much are you selling your exhaust for? Damn it, I just bought a brand new OEM muffler for my car. I'm a little late :(

[91 318is]

How much are you selling your exhaust for? Damn it, I just bought a brand new OEM muffler for my car. I'm a little late :(

Take it back!

http://r3vlimited.com/board/showthread.php?t=176956

That price is shipped too.

[trackjunkie21]

Take it back!

http://r3vlimited.com/board/showthread.php?t=176956

That price is shipped too.

The place I got it from takes no refunds. Guess i'm shit out of luck :( maybe next time. I need to make myself a system like this. Do you still have a resonator?

[91 318is]

Yeah I have resonator right where it bolts upto the mid pipe. It's short, might not be doing much

[s_ribs]

Sounds nice! Your set-up is very similar to mine, but I have rasp. Have a few questions on details:

What size/brand resonator did you use?
What are the dimensions on the muffler?

I'm running a 5x8x18" straight-through style muffler, there was a ~12" resonator already in there so I re-used it. Only difference I see is piping - mine isn't mandrel bent. From my research I was thinking that mandrel bent piping could make a difference in rasp/no rasp (it's all about how smooth air flow is and the volume of air flow), so your set-up seems to confirm my hunch.

One other curiousity- do you notice your exhaust volume changing with engine temp? Mine is pretty quiet when the car is cold, but get's increasingly louder as the engine warms up. I've never experienced that with a car to the extent I am now.

[91 318is]

s_ribs

the resonator is the one I took off stock setup, it's just round and about 12" long. The muffler is a 8" oval, 14" long. Thermal also makes a 18" long muffler also.

Funny you say that about the exhaust because yes, mine changes with engine temps, does seem louder once the muffler warms up.

[s_ribs]

Good to know yours gets louder with increased temps too. According to all theories/properties of air, it makes sense - I've just never noticed it before.

Thanks for the details on your set up. I'll have to look into redoing my piping sooner than later... rasp sucks! Do you get much drone? I only see some around 2.5k-2.9k rpms, and only when at full temp. I have some neat ideas to eliminate that if I ever get my hands on a welder. Think quarter-wave tuning to cancel frequencies. :)