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diy exhaust valve!!! pics inside!

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Old 12-19-06, 01:40 PM
  #26  
Seduced by the DARK SIDE

 
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An exhaust dump is very effective on a turbo. On an NA it can kill the standing wave resonance tune of your exhaust system.
I installed this one: www.badlanzhpe.com

In this video I had the valve just part open & the boost on low to control wheel spin on the damp road. About 9.5 minutes in I opened the dump all the way.
http://video.google.com/videoplay?do...9486451&q=dgrr
Attached Thumbnails diy exhaust valve!!! pics inside!-exhaust-valve22.jpg  

Last edited by SureShot; 12-19-06 at 02:10 PM.
Old 12-19-06, 05:37 PM
  #27  
Mazda goes MMMMMMMM

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Originally Posted by airworks-fc3s
had that thought too... may installing some sort of damper would help! after WOT, there would be some delay of closing... but now we have the heat problem again

About the "delay".

Why not use something like the dashpot on the throttle body?
It's supposed to keep the throttle plates from snapping shut. It catches the linkage then slowly releases it.

I know part of it's plastic but, if you put it far enough down the exhaust line the temp might be cool enough.

Or make your own that could withstand the heat.
Old 12-19-06, 06:02 PM
  #28  
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Awsom idea, even the new zo6 corvetts use that idea.
Old 12-31-06, 02:20 AM
  #29  
pistons go home!

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guys thanks for the opinions!

i'm now nearly done with the valve. did the major part of the manufacturing and welding. i've already hooked it up the gas pedal (the cable goes through the firewall, where the speedo cable goes) and did some testing with opening and closing and compared the to flappers (TB and my valve). i added a adjusting screw so that i can adjust my idle noise

the issue with the backpressure is still unsolved... but MANKDRAKE's idea was nice, will try it the next time i'm in the garage.
Attached Thumbnails diy exhaust valve!!! pics inside!-pict0884.jpg   diy exhaust valve!!! pics inside!-pict0944.jpg   diy exhaust valve!!! pics inside!-pict0952.jpg  
Old 01-11-07, 03:02 PM
  #30  
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Nice to see you are actually going somewhere with this idea... I have had similar thoughts but more with an vacuum or electronic valve.



To the left is the turbo, so the tought is just like you have described, at idle/low power the shutter is closed forcing the exhausts trough the smaller pipe and muffler (2" might be too small) but at boostpressure/throttle or maybe even injectorcycle the shutter opens up and let it flow trough the whole system... The thing that worries me is the room under the car, but I will take some measurements and see what can be done!

Looks promising that you are making progress and I will follow this thread with great curiousity!

/Anton
Old 01-11-07, 06:50 PM
  #31  
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personally i think it would be better to have a just plain old switch in the cockpit

toggle between quiet and loud
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