shutter sound, is it a bov?

[CougarDS]

Wondering if that shutter sound i hear somtimes is the "sequential blow off valve" or is it a type of waste gate?

It makes a noises of air that pulsates really fast when shifting or letting off the gas...i've seen it on videos...just wondering. i always thought it was the bov but my friends car made that sound and he said he had some type of greddy bov and that the sound came from the waste gate.

[yozsi]

no, thats compressor surge, when a bov or a cbv isnt working correctly.

[tbkonwso]

got clips....? i know a lot of people are confused about wastegate sound bov sound or surge sound... if u get a clip i can tell you.

[CougarDS]

http://videos.streetfire.net/search/supra/1/8F8D37F0-60B3-4200-B656-12CC15D6C160.htm

In the video before he does the run..you can hear it in between shifts...also...after his dyno run, when he lets off..there is a "barking" sound...i hear this a lot on turboed cars...what's that noise?

[tinkis]

Sounds like an HKS super sequential. They have different inserts you can buy for the bov to make them have different sounds.
http://www.hksusa.com/categories/?id=1063

[yozsi]

yea, that sounds like an hks. had one on my volvo and i hated it. so i put a porsche cbv on it.

[CougarDS]

what about the barking noise after he lets off the gas??

[Dean]

what about the barking noise after he lets off the gas??
Thats the Blow off valve.

[NotAMonte86]

Some BOV's sound like compressor surge.

You won't hear a wastegate do anything when someone lets off the gas. You usually won't hear a wastegate even when it is opening.

[yozsi]

Some BOV's sound like compressor surge.

You won't hear a wastegate do anything when someone lets off the gas. You usually won't hear a wastegate even when it is opening.
unless you run an open dp or an external WG. hehe i can definately hear my wastegate. sounds like shit IMO.

[jussie]

external wastegate (vented to atmosphere) or open DP makes car sound like garbage truck.

[tgeny79]

This is called wastegate flutter. It is not surge. Your BOV prevents surge when you let off the gas. The waste gate is what actually controlls boost. It is very common to hear it open and shut at partial throttle. You won't hear it at WOT as it is closed and building boost.

[yozsi]

This is called wastegate flutter. It is not surge. Your BOV prevents surge when you let off the gas. The waste gate is what actually controlls boost. It is very common to hear it open and shut at partial throttle. You won't hear it at WOT as it is closed and building boost.
umm, do you know what your talking about? lol you need to read how a wategate works. a wastegate wont "flutter".

[tbkonwso]

yes its the hks ssqv lol...shit i can see it from the video :p...

[BOB]

Vroom Pssshhh.....yup BOV.

[Euro_rev]

That miata video is a good example of that sound...
http://video.google.com/videoplay?docid=-7286869829674109599&q=drag+racing

[tgeny79]

umm, do you know what your talking about? lol you need to read how a wategate works. a wastegate wont "flutter".

Are you sure YOU know what you are talking about? A wastegate most certainly will flutter especially if there is an electronic boost controller regulating boost. The WG will cycle open and close (which is the flutter you hear) between shifts and at partial throttle. An electronic boost controller is a dynamic device that actively controlls boost, not just open the WG off throttle and close it on throttle.

[yozsi]

Are you sure YOU know what you are talking about? A wastegate most certainly will flutter especially if there is an electronic boost controller regulating boost. The WG will cycle open and close (which is the flutter you hear) between shifts and at partial throttle. An electronic boost controller is a dynamic device that actively controlls boost, not just open the WG off throttle and close it on throttle.
the only reason a wastegate can "flutter" is if the boost pressure is fluctuating violently. otherwise a wastegate is just a diaphram that opens/ closes at a certain pressure.

[tgeny79]

ok sure thing.