Just wondering if it had been done on a MC1 with stock exhaust manifold, downpipe and wastegate.
What differences did you notice?
Any problems with plumbing?
Thanks!

Yes I did and so did Den.
It's loud under boost and not really great sounding on a 10 valve engine.
I noticed a slight reduction in EM temp and it seemed to breather a bit better on the top end but I've got no proof or that and it's ran the same time at the track.

i recently heard a 10vt 90 with open wastegate and i really didnt like the sound of it. Under boost it sounded more like a tractor and not even a very nice tractor just my opinion

Has anybody heard how it sounds on a 20VT I5? I'd like to run an open dump on my car, but I don't want it to sound like ass.

A 20v doesn't' sound much different than a 10v. I like a completely open exhaust, but not just the wastegate.

Yeah, I'm with Dana and Myke. Actually my car is the one that Dana heard recently as I just got it going, and I was planning on running the open dump tube on the wastegate. But it's definitely a bit loud and obnoxious under boost, but maybe I'm just getting old. Anyway, I personally don;t like it, and plan on plumbing it back into the exhaust before the car goes on the street.

I'm going to!

It sounds like complete ass. Lemme find a video of a Swedish UrQ running open wastegate...it sounds wonderful until the wastegate opens then its an obnoxious rattling/rushing air/super loud/shit sound.

Edit: here it is: http://videos.streetfire.net/search/qua ... 262ad1.htm

Sam

I have an open dump on my 1.8t 20v, I know its not the same car but it still sounds like total ass!

Hmm... well, I am thinking that the WG will be mostly shut under boost. I am going with either a big-housing GT35R or a 35/40.

Then again, if the WG is going to be mostly shut, what is the advantage of dumping? I guess nothing.

I have a dump tube on my 10vt and it is getting plumbed back in to the exhaust soon!

You could always stick a mini muffler on the WG dump like they did on the 930's and such. I always thought it was pretty funny, here was this tiny little muffler hanging off the WG dump pipe. Looked like a can of beans. I think at that point you're seeing diminshing returns- unless you have a Porsche and no room for an exhaust system as it is.

Well, room for exhaust (room for anything) will be at a premium in my car. In case you haven't seen my project thread, this is an Audi Fox Quattro I5 20VT project.

Sounds like I need to plumb the wastegate into the exhaust and forget about it.

The wastegate will open as soon as you hit your target boost, I had one on my 1.8t, and I grew to hate it. Way too loud.

The sound on a 10v engine sucks, sounds like a bad exhaust leak, but it will effectively increase your downpipe size by removing WG flow from the DP and exh system.

i thinkim gonna make a seperate wastegate exhaust, somthing that will take it 1/2 way back on the chassis and then dump it under the car. or maybe all the way to the back.

Just be careful not to add another 40 lbs of weight to your car for now reason

I ran it open before and didn't mind it. Then again I don't even know why I run a WG because it's always closed trying to keep the boost up.

That URQ sounded nice until all of a sudden it DIDN'T. Then it sounded like shit.

I think it sounds good, i'll be running my 10vt open and get videos. I'm sure i'll eventually get sick of it, but i have a factory exhaust and i want to open it up a little for boost (by just dumping the wastegate) without it being obnoxious on the highway, just obnoxious when i floor it.

i think that the bold statements of the 20v sounding like ass with open down pipe is a matter of preferance. i may be a young gun punk ass that likes stuff loud but i dont think it fare to say it sounds like ass. you can hear the turbo in all its glory, and the nice a clean combusted material making its way out of the motor. oh i love it, call me crazy i dont care.

Im with ya there uti
I've always loved forced inducton whine

I'm sure I would love it daily too!!

sssssSSSSSS!!!--Ppsshshhhh!!! (Boost and blow off sound)

It is fun in the beginning, scaring the bejesus out of little kids and old people, but it gets really old after a while..I won't go back to open dump again..My grey car is plenty loud with twin 2.25 straight pipes from the turbo back to the rear bumper, the sound has been compared to an S1 albeit not THAT loud..The problem is that all hell breaks loose and your concentration on important things such as the road, other people, engine speed, detrimental noises, is basically tossed out the window with the instant blast of open exhaust, unlike straight pipes which are loud throughout the whole range, and you still hear the turbo spool..