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Hey guys

i know this topic has been covered before but there are a few other things i wanna know.

ive got a pretty well stock r33 skyline that im lookng at modding, now im pretty certain im going to be doing a highmount 3076 740s etc etc.

now the intercooler kit im looking at getting i DONT think has a place for the bov, it replaces that first piping bit that the bov sits in. now

im wondering do i NEED to run a bov? i know people have problems with idling etc but unsure if thats all because of the bov. as there are

alot of hoses/pipes that run of that first pipe im not to sure were there going to go when i install the fmic (bov being one of them)

any help will be mostly appreciated

Thanks Adam.

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Run a BOV. A stock one. And call it a compressor bypass valve, because that's what they really are. And add a conection point to the pipework just before the throttlebody if you have to, and add a connection point to the turbo inlet (angled towards the compressor snout) if you have to.

Job done.

If you're using a MAP sensor based ECU don't worry about running one, AFM better off running one, but isn't a must.. you can adjust the decel fuel cut to compensate for it.

I'm not going to start the BOV or no BOV war :nuke:

I never run BOVs, but that's just me.

yer i was thinking of running no bov but ive been told there are all these issues with idle etc, il be running a power fc with z32

Not all true, I've done it before and stuffed about with the decel fuel cut in the same table as the idle control to stop it from stalling on decel.

If you're running a stock ECU than you'll have "some" idle issues, like if you're cruising then clutch in your motor will stall but easy workaround is to gear down or bleep the throttle.

I spose it depends who tunes it. Within 3 runs of having mine blocked off (due to the ARC twin entry cooler), Yavuz got out of the car and started looking around. Also, something you don't see on the dyno was the throttle response between gears suffered significantly because of it.

The people suggesting that you dont worry about it have not mentioned the downsides. Piggaz did, so IMO his post is the most useful in this thread. If you're not sure if you can be bothered fitting one, do some research on what BOVs do, then you can decide if its worth it or not.

  • 2 weeks later...

im not running a bov on my mildly built rb20det! im running my afm in the cooler piping near the throttle body and no bov and it idles fine boost fine and goes hard! if you look back to the old 31's and vl's they didn't run a cooler or bov from factory.... plus i fond running no bov more responsive being that the cooler is still pressureized cause when you run the bov it lets all the pressure out, but its up to you how you want to set it up :)

Im not running a bov on my 33, no issues at all and no downsides. I have had no bov on all my cars, most if not all stock ones leak due to age. Im not sure why some guys are having issues with idle or decel without one, they might have there afm mounted in a non stock position?

All the people that say that having no bov is bad and will cause turbo failures Im yet to see any fail from not having one. A mate at work is running a 3076r with no bov, stil going strong after 3 years of 21 psi and 290rwkw,.

Im not running a bov on my 33, no issues at all and no downsides. I have had no bov on all my cars, most if not all stock ones leak due to age. Im not sure why some guys are having issues with idle or decel without one, they might have there afm mounted in a non stock position.

Stock ones leak ah idle/low throttle - on purpose - do you realise that is how they have been designed?

Plenty of people here running stock ones at 300Kw/20psi that don't leak under load, its like all things, age and condition of components.

You are one of the lucky ones with no issues, so good work there. Plenty of before/after posts around for people to read to show that there can be issues, most of it related to the tune as you need to compromise sometimes with the fuelling (non BOV) to stop the stalling.

so its not essential. But doesn't hurt - that's where the decision gets made really by the OP

All the people that say that having no bov is bad and will cause turbo failures Im yet to see any fail from not having one. A mate at work is running a 3076r with no bov, stil going strong after 3 years of 21 psi and 290rwkw,.

Not one person has said anything remotely close to that in this thread, or on the pages of this forum for YEARS now really.

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