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here is a free mod that you can do to your standard skyline bov which will improve your throttle response..

if it has been posted before, then too bad..

I have found a mod that can be done to the standard skyline bovs to make the car a little more responsive without any side effects.

What you will feel is that the boost will come on quicker and the bov will not release till a little later.

meaning that you won't have that constant re-circulating sound you get with the standard bov.. (this sound is heard more if you have a pod filter..)

here is what you do..

take the standard bov off.

look at the bottom of it..

you will see the piston on the hole, then a small hole next to it.

you will need to find a small screw that will fit the hole.

the screw needs to have a FLAT head so that it doesn't protrude too much above the bov plate.

What I did was found a flat screw which fit in the hole easy, then I wrapped it in that plumbers tape (the white stuff) until it was fat enough that it had to be screwed in.

once in, I used some super glue on top to make sure that it is completely on there..

let it dry, put the bov back on and go for a spin..

You should be able to feel the difference..

no more KW's but I think that it comes on boost a lot quicker and doesn't release so early like a standard one does.

if you have any questions or want help doing it, then let me know.

the pics below are not mine but it shows what I am talking about..

bov.jpg

bov_blocked.jpg

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it doesn't get rid of the sound.

it just doesn't circulate the air unless you are like 10 in to the vacuum side of the boost guage..

normally, it will circulate the air at even just above 0..

this is all according to my boost gauge..

plus the spool up of the turbo is much quicker.

You will still hear the swoosh sound between gears and it will still re-circulate the air.. as it should..

but it just makes the car nicer to drive.

as for why the hole is there in the first place?

I'm not sure..

probably so that the bov doesn't have to open to circulate the air at normal cruise speeds/boost levels.

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thanks heaps for that. i am not going to do it, till i get the car started, so i can tell if it makes a difference.

why do nissan put it there, same question i have about why they have the throttle body in the position they do. should be at the front, makes cooler piping waaaaaaaay easier.

should have a front mount too.

thats just my bitch.

but good bov idea.

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i did this mod thiss morning and removed it about 15mins later.

on about 10IN-Hg to 3psi you get the air reversion flutter noise

but once on boost and you change gears of snap the throttle closed you get a combined flutter and half ass 'psssht' bov noise. Made the car sound like something was wrong with it. I dont know if it was just my bov but it didnt sound too good.

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haha yep followed them .. pretty easy to do...

the screw was in there tightly, with plumbers tape wrapped around... i had to force the thing in, so it was very tight and secure.

it had a nice flutter on low spool, but once i stomped it abit and let off it had a flutter mixed with the pssht at the same time... kinda sounded like the bov was dying :P

and i do have a r32 rb20det, so its not a NICS engine problem :(

maybe the vale has a weak spring in it... i dunno i just took the screw out

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lol well I ****ed mine completely. I put the screw there, it was fine. then it sounded monged. Got scared and tried tightening more in case it was the air escaping. Then the F*#KING bolt snapped :D

Had to take the whole pipe off to remove it. But I don't have another bolt. At least I might as well polish the pipe now.

I also lost the bit that goes in between the bov and the pipe the spacer tightening thing. It fell down into the engine, but it was night time and I cbf looking for it. Is this necessary? Does it matter if I need it?

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  • 2 weeks later...
  • 1 year later...

If you have an AUTO - DON'T screw around with this BPV - BY PASS Valve!

If you have a MANUAL - DON'T screw around with this BOV - Blow Off Valve.

If you dont realise the difference, dont screw around!

But consider instead of letting your boost reference for the wastegate be from the snail of the inducer where it comes from as standard, plumb it in to your intake manifold so your waste gate opens a bit later when the boost is actually at the intake of the engine. Caution, this could over speed your turbo:-)

Obviously you block the orig. hose from the snail to stop airleak.

You could also hook the hose from the BPV/BOV to the Intake manifold direct as well for better response.

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  • 11 months later...

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