Which Dv gives this sort of sound

[neil_jdmr]

http://www.youtube.com/watch?v=F4XDtADd0n4
 
This rx7 gives a different type of sound when dumping off its sounds similar to cetain supras anyone identify it?
 
All the rx\'s ive been in have the usaul woootsshhh sorta noise if you know what i mean, watch the link you\'ll see
 
Cheers

[m4drx]

thats compresser surge mate or waste gate chatter as its commonly known.

basically no DV at all or poorly positioned/inadequete one.

[neil_jdmr]

AAhhh right,
 
I know of wastegate chatter but this sounded just too loud for that, a friends gtir sounded exactly the same.
 
Is wastegate chatter bad for the car then as i was under the impression that dump valve\'s did little or nothing anyway bar making the "look at me" noise
 
I realise its supposed to release the back pressure from the exhaust to allow the turbo to spool up better but does this actually work???

[m4drx]

the excess boost on its way to the engine that gets cut off by throttle body butterflys snapping shut go back towards the turbo. if this boost is not released (dump valve) or recirculated like most stock systems on turbo cars then they will go back into the turbo and cause it to stall. the noise you hear is the noise from air rushing the wrong way round the turbo. this is in many peoples opinions bad for the turbo (not engine directly).

i however still search for a magic dv that makes that noise :rollin

[Jono FD3]

The blow off valve (dump Valve) basicaly releases the pressure from the intake system between gear changes (nothing to do with the exhaust) this allows the turbo blades to maintain a forward movement rather than the pressure having no where to go resultung in back preasure in the intake, and the stalling the turbo(s) between changes!!!!

Jono

[RobbieRX-7]

That noise is a dumpvalve. I think it\'s an HKS SSQ or summat like that. There is a website round somewhere with all the diffrerent dumpvalve noises http://www.youtube.com/watch?v=gVBBO4w78U8

[m4drx]

mate i dont see how it can be possible to create that noise at all. Pressure is released when it open whooosh...thats it?


if someone can confirm then wohoo but atm i must say its impossible at the moment.

[skybusr34]

have to agree with robbie. i`ve heard a dump valve that sound like wastegate chatter. don`t know the make though. sorry bud

[Rzla]

yep i agree toooo, definetly a dump valve
i have heard a dump valve make that noise on a very nice black car i once used to know .... lol .... L to the a to the q

[Rzla]

 http://videos.streetfire.net/video/31a65330-4e17-4373-bdab-e2c87adc0361.htm
:god:god

[rico2k_uk]

no dump valve there.. thats what teh skyline sounded like when the recirc and dv were removed  

[Rzla]

no dump valve there.. thats what teh skyline sounded like when the recirc and dv were removed

i know the person who owned the rex in that video
believe me he had a dump valve in it the engine was bling :Thumbs-up

[m4drx]

tis laeeqs car.

and ive just asked him and it had no DV at all.

[rico2k_uk]

lol!

my skyline was like that with no dv :

[TonyC]

My RX makes that noise. Single turbo, no Dump valve.