Wastegate dumped into exhaust or vented to atmosphere?
12-09-2010, 10:59 PM
#1
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Wastegate dumped into exhaust or vented to atmosphere?
Any upsides or drawbacks to either? I've heard that with it vented to atmosphere it will sound like a jet at WOT. I don't know which one to go with, any input?
12-10-2010, 11:11 AM
#5
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Re: Wastegate dumped into exhaust or vented to atmosphere?
Nothing wrong with dumping it IMO. It's real the difference between the sound. Ifryou want to sound like a jet plane under WOT, or be more stealthy.
12-11-2010, 01:58 AM
#7
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Re: Wastegate dumped into exhaust or vented to atmosphere?
Here's a HD burnout video of my car. It makes a hell of a woosh sound when the wastegate opens, WG dumps to atmosphere, as you can tell 
http://www.youtube.com/watch?v=8hvxUaadk1M
http://www.youtube.com/watch?v=8hvxUaadk1M
12-11-2010, 11:05 AM
#8
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Re: Wastegate dumped into exhaust or vented to atmosphere?
MIne is currently vented to atmosphere and it does indeed sound like a jet or a compress air hose that's been cut. I'm going to redo mine to exit into the intermediate pipe.
12-12-2010, 01:56 AM
#9
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Re: Wastegate dumped into exhaust or vented to atmosphere?
Well I'm assuming that once the turbo spools up stealth really isn't an option is it?
I hopefully plan on building one here pretty soon...exiting back into exhaust a little better you think?
I hopefully plan on building one here pretty soon...exiting back into exhaust a little better you think?
12-12-2010, 05:33 AM
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12-12-2010, 09:52 AM
#11
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Re: Wastegate dumped into exhaust or vented to atmosphere?
I just love the baffled looks on their face (especially the sport bikes) when I pull away from them but I want them to think it's a stock sounding LT1 
Everyone knows that LT1's are slow
I've had LSx owners get loud after I've beat them. They've rolled down their windows, started yelling "That ain't stock! That ain't stock!" while their passengers were sitting there laughing. I can only imagine the conversation before the race.
<LSx driver>"Look at that ******** in the LT1. Let's have some fun. These guys always think they're hotsh*t with the puke LT1's..."
<snicker>
Everyone knows that LT1's are slow
I've had LSx owners get loud after I've beat them. They've rolled down their windows, started yelling "That ain't stock! That ain't stock!" while their passengers were sitting there laughing. I can only imagine the conversation before the race.<LSx driver>"Look at that ******** in the LT1. Let's have some fun. These guys always think they're hotsh*t with the puke LT1's..."
<snicker>
12-12-2010, 09:27 PM
#12
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Re: Wastegate dumped into exhaust or vented to atmosphere?
From what I've read, unless the merger is smooth, dumping into the exhaust can create turbulence and added back pressure. I don't know if that pertains to big V8's with large downpipes as it was just random information I read while googleing the subject.
12-13-2010, 12:50 AM
#13
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Re: Wastegate dumped into exhaust or vented to atmosphere?
Well turbulence is never good- so I would assume there is some truth to that...although like you said I bet it would affect a smaller displacement motor more..
The velocity and volume of the exhaust on a SBC is so great that unless you deliberately plumbed it against the flow I doubt it would make that much of a difference- but I'm just speculating..I'm not an engineer.
The velocity and volume of the exhaust on a SBC is so great that unless you deliberately plumbed it against the flow I doubt it would make that much of a difference- but I'm just speculating..I'm not an engineer.
12-13-2010, 01:40 AM
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Re: Wastegate dumped into exhaust or vented to atmosphere?
It's not rocket surgery. Just imagine if water was flowing through the pipes, you wouldn't want to introduce it back in at a 90 degree angle or anything. I wouldn't do it on the outside radius of a bend either because thats what the air is slamming into and causing it to change direction.
12-13-2010, 06:37 AM
#15
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Re: Wastegate dumped into exhaust or vented to atmosphere?
Again- this is just theory as I don't have a turbo (yet) and am just trying to pick up info where I can...but let me throw this out there for those that know more than me...
1.)The piping before the turbine is going to be higher pressure than the area after the turbine due to the exhaust gases having to work to compress the air on the compressor side.
2.)The wastegate bleeds off excess exhaust pressure to prevent over-boosting.
3.)The velocity of gases from the wastegate piping would therefor be higher than those in the downpipe due to the increased pressure
If all the above are correct then mounting the wastegate piping into the outside of the elbow to flow straight thru the elbow then the higher velocity of the wastegate gases could help pull exhaust gases thru the elbow since high velocity gases entering a larger area creates a vacuum with it if I remember correctly from physics class.
Now this is strictly theory..hopefully nobody jumps down my throat. Thoughts? Just trying to learn some stuff and present ideas..
1.)The piping before the turbine is going to be higher pressure than the area after the turbine due to the exhaust gases having to work to compress the air on the compressor side.
2.)The wastegate bleeds off excess exhaust pressure to prevent over-boosting.
3.)The velocity of gases from the wastegate piping would therefor be higher than those in the downpipe due to the increased pressure
If all the above are correct then mounting the wastegate piping into the outside of the elbow to flow straight thru the elbow then the higher velocity of the wastegate gases could help pull exhaust gases thru the elbow since high velocity gases entering a larger area creates a vacuum with it if I remember correctly from physics class.
Now this is strictly theory..hopefully nobody jumps down my throat. Thoughts? Just trying to learn some stuff and present ideas..