ok, this valve is great. at least great for the price. but when i called greddy, after looking online, etc... everything i found was for me not to hook up the smaller lower nipple. thankx greddy. dont get me wrong, they have alright products, but i called them and this is what they told me. anyway, they were wrong. you CAN leave it open, but it is designed to have the turbo pressure that your wastegate is feeling pushing underneath the piston, so that when you remove you foot from the gas, or there is a pressure diff. between the two, recirculation, or blow off, occurs. note, the single line to vaccum will work for non recirc, but was giving me trouble with recirc. this is the reason i looked further into it. i would say go ahead and hook up both lines
top one to manifold press, smaller bottom fitting should feel the wastegate signal.
hope this helps someone, it helped me :ylsuper
ps. i hooked this up to eliviate the idle drop problem, which it did. too bad i am hooking up hks super afr tomorrow. this fixes this problem (hopefully)
greddy type-s bov for real
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The greddy type R valve I am using did not work at all with just the upper(intake manifold) line attached. When I ran a line to the lower nipple from the wastegate feed, it worked fine.Like he said, the greddy BOVs need pressure under the diaphram to overcome the spring, the vacuum, just breaks the seal and gets things started.
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Cyberkreig
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for greddy valves:upper nipple: intake manifoldlower nipple: tee off of wastegate feed lineits that simple.
If you use a bov like a blitz, that only has a vacuum nipple, then it may leak under idle. I had this problem before, I tightened down the preload screw all the way and the thing was still doing it.THe greddy uses a stiff spring that needs to be overcome by two pressures: the vacuum in the intake manifold and boost at the turbo.
If you use a bov like a blitz, that only has a vacuum nipple, then it may leak under idle. I had this problem before, I tightened down the preload screw all the way and the thing was still doing it.THe greddy uses a stiff spring that needs to be overcome by two pressures: the vacuum in the intake manifold and boost at the turbo.
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Cyberkreig
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i think you might be right about that.i disconnected my recirc right after i finished setting my super afr on a dyno, and i have mad probs. could be the afr, right now i cant tell. basically the prob is, only when lifting slightly off the throttle, the motor stumbles, backfires, acts shady. boosts well and the a/f is strait. anyone got any hints on this hks ****.
by the way, some guy at altered atmosphere reccomended that i take my car to this place called turbo tune, he new cars etc.. but had never seen the super afr nor did he know how to tune it. very interesting.
by the way, some guy at altered atmosphere reccomended that i take my car to this place called turbo tune, he new cars etc.. but had never seen the super afr nor did he know how to tune it. very interesting.
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caliracer240
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I'm lost. Okay, my Type S has 2 nipples, plus the big bov part. The upper nipple is hooked up to the intake near the throttlebody (if I remember right) adn the lower one is hooked up to nothing. I leak under high boost pretty bad. And mine is pretty tight. What is this about me hooking up the lower one to the wategate? What will that do? I don't get it. Will it adjust it with the boost to make it hold better when it's actually boosting?
I am not sure. You can try capping it and see what it does. Have a buddy check for leaks as you rev and let off. If it is still a problem just hook up a line from the wastegate signal.
I and I lied about getting my top signal from the hotpipe. I was a little confused at the moment. Mine pulls from the TB.
I and I lied about getting my top signal from the hotpipe. I was a little confused at the moment. Mine pulls from the TB.
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OK OK, dont cap the lower (small ) nipple. As the diaphram in the BOV moves up and down it will displace air in and out of that nipple. BUT, if you blow into that lower nipple you will notice that it is leaking out somewhere. If the small nipple is capped, then the air the diaphram displaces when it moves will all be forced out that small leak hole (where ever it is). WIth the nipple uncapped, the displaced air can travel in and out of the nipple, which is a more unrestricted path. So, in threory, your BOV should be more responsive with the lower nipple open to atmosphere.When the throttle slams shut under boost, the sudden increase in vacuum from the intake manifold will be the only force overcoming the spring & opening the valve (well, and the pressure on the plunger from inside the pipe, but lets not think about that).
By hooking that nipple to the wastegate feed line(optional), then when your throttle plate slams shut under boost, the upper BOV nipple sees a **** load of vacuum and the lower nipple sees a ****load of boost, this pops the bov open until there is not enough pressure difference to keep it open, then it shuts.
When should you hook up your lower nipple??? Heres my 2cents: when it works better that way.Seriously, use the lower nipple if you have to have a lot of preload on the spring to keep the valve closed at idle, the added push from the boost coming in through the small nipple will help overcome this spring force when the time for blow off occurs. Try both ways, see what works best for your setup.
Also your valve should not be leaking at high boost levels (unless it is defective or hooked up wrong). During these periods, the whole system is pressurized, even the intake manifold. Since you have a line going from the intake manifold to the upper(larger) nipple, then that line is pressurized too, forcing the valve close (along with the spring force).
By hooking that nipple to the wastegate feed line(optional), then when your throttle plate slams shut under boost, the upper BOV nipple sees a **** load of vacuum and the lower nipple sees a ****load of boost, this pops the bov open until there is not enough pressure difference to keep it open, then it shuts.
When should you hook up your lower nipple??? Heres my 2cents: when it works better that way.Seriously, use the lower nipple if you have to have a lot of preload on the spring to keep the valve closed at idle, the added push from the boost coming in through the small nipple will help overcome this spring force when the time for blow off occurs. Try both ways, see what works best for your setup.
Also your valve should not be leaking at high boost levels (unless it is defective or hooked up wrong). During these periods, the whole system is pressurized, even the intake manifold. Since you have a line going from the intake manifold to the upper(larger) nipple, then that line is pressurized too, forcing the valve close (along with the spring force).
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caliracer240
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Ya, it was..
Mine does leak under boost though. I don't want to buy a new one. I'll buy a new spring if I can find one. It's hooked up correctly. I can provide pix if you wanna see. But will hooking up the lower one possibly make it hold shut easier while boosting? Maybe preventing it from leaking under high boost?
Mine does leak under boost though. I don't want to buy a new one. I'll buy a new spring if I can find one. It's hooked up correctly. I can provide pix if you wanna see. But will hooking up the lower one possibly make it hold shut easier while boosting? Maybe preventing it from leaking under high boost?
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caliracer240
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