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I'm thinkin' of blocking off my standard BOV in my 32 so I get the flutter but I've been told different stories my people.

Does anyone know FOR A FACT if it does any damage/excessive strain to the turbo? Or is it absolutely safe to do?

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I have a piece of a compressor wheel from a rb20 turbo which blew out of my friends exhaust.

He blocked off his bov and was running 14psi..

Whether it was the blocked bov or the 14psi, i still have a cool looking piece of ceramic :/

ive had mine blocked off for a while now however i only blocked it off as my stock one was leaking under boost...ive recently bought a greddy type s bov..got it off a mate cheap and only bought that one coz couldnt get my hands on a gtr bov..

but the fluttering is fine...i still remember driving past some yr 8 skool kids and letting the flutters go off lol all i could here from the kiddies was ohhh woooww hehe i a had abig grin then lol

i don't think it'll effect it much if you're running standard boost! but if you start uping the boost it'll be safer to leave the bov the way it is!

and if you want a flutter you can get an aftermarket one and tighten it

That's exactly what I think! That's why I'm unsure.

lots of cars dont have them and run fine. mine never had one from factory. u know why manufactures use bov's now..? noise polution. they dont want weird tu tu noises coming form their engines. the average person buying a car would be like wtf that aint right. thats why some cars come with 4 cats in their exhaust systems when only one is required. to keep cars running smooth and quiet.

Edited by steveP

The reverse flow back across the turbo acts on the compressor wheel and causes the turbine shaft to reduce in speed quicker than it would naturally. When the throttle is opened again, the turbo will have to make up for lost momentum and will take longer to achieve the required speed, as turbo speed is proportional to boost/volume flow. (This is known as Turbo Lag) In order to prevent this from happening, a valve is fitted between the turbo and inlet which vents off the excess air pressure. These are known as an anti-surge, bypass, blow-off (BOV) or dump valve. They are normally operated by engine vacuum.

but a bov releases all the air. with no bov, the air between the turbo and throttle body gradually escapes back out the intake system. during gear change or whatever, theres still boost in the intake pipes/cooler, so it wont need to spool up all over again.

and before someone goes emo and cuts themselves saying it damages ur turbo. turbos are very robust. they handle high boost pressure and extreme heat for 100,000+kms (average life of a turbo). so releasing the air back out the intake system 'a little slower' is going to do f**k all to a turbo.

Edited by steveP
I have a piece of a compressor wheel from a rb20 turbo which blew out of my friends exhaust.

He blocked off his bov and was running 14psi..

Whether it was the blocked bov or the 14psi, i still have a cool looking piece of ceramic :/

That is from the 14psi through a stock turbo, Blow off valve will not effect the rear wheel nor will it effect the front wheel as much as you think. The main concern when not using a BOV is because the sudden surge of back pressure puts strain on the bearing and seals inside the turbo from the back and forth movement it will get during this time. A blocked Air filter can also cause alot of wear.

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