Dumpvalves

Gary57 · Post by **Gary57** » Wed Jan 31, 2007 3:32 pm

Hey guys I want my dumpvalve to give that chatter rather than the tttssssshhhhhhhhhh. What dump valve will do this?? Also I want the trumpet to be adjustable, I dont want this thing loud, it must be subtle.

Dislex666 · Post by **Dislex666** » Wed Jan 31, 2007 3:51 pm

that chattering noise you talk about i (along with the SXOC in the UK) call 'pigeoning' it's made by the sound of air going back over your tubbys impeller (kinda like talking into a fan

)

anyway - it's achieved by not letting the BOV dump as early as normal - you need an adjustable one.

my SSQV is like this. If you want the spring in (make it tighter - so need more boost to open it) then it will give you both noises...

however - after taking my old turbo off it had LOTS of play... which i blame on the pigeoning. So now i've wound it out, i barely look at the petrol pedal and it goes PSSSSHHH

veecee · Post by **veecee** » Wed Jan 31, 2007 3:51 pm

chatter is usually heard from an internal wastegate!!!

when i changed to a cone filter, that sound became very prominent in my daily driving, but only because i still dont have a BOV installed.

i reckon once the BOV is in there, the wastegate chattering will be drowned out by the whooshing, cos i really dont like the whistling types, and i want a loud one!!!

edit = doesnt my post look the fool now!!!! thanks dislex!!!
edit = but it does explain very well the difference between the sounds when the cone is there vs the normal airbox!!!

Gary57 · Post by **Gary57** » Wed Jan 31, 2007 3:54 pm

its just that chatter sound so much better than tttsssshhhhhh. The 1980/1990 rally cars made this chattering sound.

Gary57 · Post by **Gary57** » Wed Jan 31, 2007 4:01 pm

that chattering noise you talk about i (along with the SXOC in the UK) call 'pigeoning'

Oh my ja that right it sounds like a pigeon. Oops my bad only got it now

.

Dislex666 · Post by **Dislex666** » Wed Jan 31, 2007 5:12 pm

that type of chattering can also be caused by antilag systems - fuel LITERALLY exploding inside the turbo mani...

kills the turbo in like a coupla 100km - but sounds piss cool

Vlade · Post by **Vlade** » Thu Feb 01, 2007 8:08 am

Hehe yeah that sound was like a TSSSHHHHTRRRR BA BA BA.... The japs calls it the Bang Bang system... it was a way of Anti-Lag to keep the turbo from stalling...

http://www.rallycars.com/Cars/bangbang.html

Here is some you tube viewing pleasure...

http://www.youtube.com/watch?v=XaxhTnB-eos

Hennie Marais · Post by **Hennie Marais** » Mon Feb 05, 2007 8:41 am

Only crap thing about a atmosferic BOV on the stock management with the AFM is that is it has to stay closed at idling and only open at rather high vacuum and boost. But then you still overfuel in the time it's open. But fitting a recirculating one will not cause any problems.

Dislex666 · Post by **Dislex666** » Mon Feb 05, 2007 9:44 am

that's why running MAP sensor rocks

Gary57 · Post by **Gary57** » Mon Feb 05, 2007 9:49 am

ok regardless of the pigeoning, the dumpvalve I have now will be too loud to dump into atmosphere. Its a Xcell super-sequencial with US patent, so its good. I want to hear the dumpvalve but it will irratate me if its too loud. Anyone seen one that you can adjust the trumpets??

Hennie Marais · Post by **Hennie Marais** » Mon Feb 05, 2007 9:54 am

I've seen on the netthe one that you have a dial inside the car to adjust the "sound" of it. The BOV is motorised so it can be vented to a trumpet or like a plumback one. Now why would one want something like that.

Gary57 · Post by **Gary57** » Mon Feb 05, 2007 10:07 am

Thats not what I want at all. Just want one that I can set how loud it is. There was one at autostyle once but not sure what it was called.