I saw a bit of mention of Dynomax in searching but for a different muffler design of theirs. As far as I can tell only robstah is using one but he has a V8.

Anybody got a Dynomax VT muffler on their 944? How is the sound? Does it work to kill the 3000rpm drone?

 

I can let you know in a few months, it's probably the muffler I'll end up running on my 3" or 4" exhaust (if I can find one with a 4" inlet/outlet)

 

What's this 3000rpm drone you speak of?

 

with an aftermarket catalytic converter (aka no resonator like the stock cat came with) and an original muffler (with any packing long since blown out) the exhaust resonates around 3000rpm (~80-85mph with my trans) and its kind of annoying on long drives. there's enough wind noise as is (even with new seals on the sunroof/hatch) and cutting the baaahhhhhhh out of the equation would help a lot.

 

Gotcha. Guess I don't know cause I went from stock straight to a resonator/muffler setup.

 

I have one on my Volvo 740 turbo. I elected for the model made for engines over 4.0L because I wanted it to be extra quiet and I thought my upgraded turbo would be able to move enough air to open it up(even called them and confirmed this). I really can't tell if it's opening or not but the car is not very loud at all. I have a 1/4 mile video somewhere but its not even worth posting because you can't hear anything. I guess this doesn't really help, don't get that model haha.

Also it does rattle at idle a little bit, but its not that bad.

 

Yes I have one on my 951 with a Lindsey 3" exhaust.

I have been quite happy with it. Makes the car a lot more civilized to drive at highway speeds.

 

These are things I wanted to hear. I figured the larger displacement variant would be a fine choice since our engines are pretty big and thumpy as is, and I'll be pushing a lot more air out the pipes soon.

How does it sound under full throttle?

For the occasional rattling, it seems that some of the earlier variants of this muffler had some clearance issues with the flapper valve so it would rattle when closed, they apparently fixed the issue around beginning of last year but there are still probably old ones out there on shelves.

 

Changed my cat to a Magnaflow 91006 w/2.5 pipes on my '87 NA a couple of days ago. Original had 26 years and 123k miles on it and although you could still see daylight through it the performance difference felt like I added 15 to 25 additional horse power. Only down-side is the buzz or razz sound that was added to my exhaust note. I hadn't expected that and will be perusing more posts down the road to see if a replacement muffler will get rid of the buzz.

 

Don't forget that you can "tune" the sound of the muffler with the "muffler tip" that you choose and its length.
I have the magnaflow cat with a stock turbo exhaust on my 86 n/a. Before I chose a tip for the muffler (the stock tip was cut off 3 inches from the muffler body) I grabbed a piece of muffler pipe, and was quite surpised the difference it made. With no tip, the car was unbearable even at idle. I tried various lengths and found I could change the sound significantly. I settled on a pipe that ended almost even with the bumper. It gave the right amount of sound and not crazy on the highway. Obviously my results will vary from others depending on their setup, tip choice, and sound preference.
As a side note, the direction in which you direct the tip also changes what "YOU" hear in the car.
As a second side note, pointing the tip down will quiet it down for other motorists/pedestrians.
Cheers!

 

One other thing. Stainless is also more raspy sounding that an equivalent mild steel setup. On my Datsun turbo car, I used header wrap and SS safety wire to wrap several feet of the pipe under the passenger cabin to cut some of the resonation/raspy sounds.

 

verrry interesting

 

Howdy Rocket..
Here is my Dynomax Super Turbo:
http://www.summitracing.com/parts/wlk-17733/overview/

And here is the exact sound of it:

Cheap as dirt and not a stainless unit of course, but I like the sound alot.
Considered the VT with the flap but once it opened up, I was not a fan.
Cheers, mikey