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hey just a quick question im unsure about, saw a r33 the other day with a huge ass flutter, liek really loud. anyway pulled up to him at the lights and asked him what bov he was runnin or whatever, and he reckons hes blocked of the standard bov ( r33 gtst). Sounded alright but just wondering if blocking of the standard bov would be harmful to the engine (they were obviously put there for a reason). He also mentioned it was runnin 10psi. Would that put more strain on the turbo, as theres no bov in action. Im sure your thinkin ohh no not another bov thread, but jsut from experience what would the likely conclusion be with a setup like that. He said the car was stock apart from boost, 3" turboback and fmic.

THanks heaps guys much appreciated.

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https://www.sau.com.au/forums/topic/105848-blocked-of-standard-bov/
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haha, talk about opening a can of worms...

From what I hear, from reputable sources, ie. mechanics and tuners, no it wont harm your turbo, your engine will idle shite and stall though. Above 14 PSI it is recommended that you use a BOV, but even then alot of drag car buliders still dont use them.

1) open turbobygarrett.com

2) browse to technical area

3) read up on the blow off and recirculation valve systems

4) understand how it affects the turbocharger system and what happens if you block it

it will harm the turbocharger end of story

We tried this trick whilst doing the turbo upgrade... I can confirm that it idles like shit and stalls... don't do it if you can resist the sound factor.

If you want flutter etc, get a proper BOV.

its all urban myths and drift / vl turbo hype

it makes the response worse

it causes compressor surge

it puts stress on the compressor wheel and shaft

there is nothing good about running with no bov

no bov on either the r32 or the s13 (sr20) and no probs on either gonn put the boost up on the s13 to bout 14 pound and see what happens but the 32 is boositing bout 11 pound happily and with a little lag that its always had. the 32 has a supra front mount on it the s13 the stock side mount. both have pods and stock turbos. i wanna put stainless intake pipes on to make it more enjoyable. i personally can see the point of a bov in a hi boost instance but in both my cases whic are pretty low i feel it shouldnt make any difference. the 'stress' they say it puts on the shafts of the turbo should be minimal as it would be more engine braking then anything else as the exhaust gases get caught in the engine more as they would slow down also in proportion. i feel its a matter of taste to go with or without BOV. until someone shows me a turbine that has shatter due to this i will keep our cars without running BOV unless i can get the chinky one like the M3 out of the mischief dvds lol

Edited by daler32
until someone shows me a turbine that has shatter due to this i will keep our cars without running BOV unless i can get the chinky one like the M3 out of the mischief dvds lol

Noone will show you a turbo that is rooted due to running no BOV. Its "theoretically" possible, but NOONE has proven it and NOONE will. Its myth and BS. I have two s13s that have never run BOVs and turbos are still in excellent condition and both have been running for 16 years....

BOVs are to reduce noise.

BOVs are to stop your cooler pipes from blowing apart if your piping is dodgey.

Thats it.

So please, before another person says no BOVs damage your turbo, post some proof. Guess it stops there, 16 years of no BOV for me is proof enough BOVs are not needed.

Now its just a personal preference what sound you want, flutter vs everyone-look-at-me-I-sneeze.....so keep it at this cause it wont be proven BOVs damage turbos.

noone said blow off valves in general damge the turbo....

only that blow off valves blocked to achieve the ghey flutter noise is harmful. read and understand fully before posting.

second of all if blow off valves arent needed why do they come stock standard with them in the first place?....

please read http://www.skylinesaustralia.com/forums/in...ic=60655&st=100

it was recently discussed

i believe the bov was fitted to prevent turbine and compressor damage. i dont believe it has anything to do with noise, emissions, looks. purely servicing on the turbocharger components and to prevent excessive failure/wear and tear

K what about this for proof then say what u will, correct me if im wrong ok.

RB20DET R32 yeah its got a bov, Goes "shhhhhh"(or whatever) due to bov

VS

RB20DET Laurel, Cefiro no bov, Flutter due to no bov.

OK im not sure if the turbos are different but theroedically(spelling) u could block the bov off on the r32 to make it the same as the Cefiro or Laurel.

Yeah whatta think? Is that proof? or not? dunno.

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