tial BOV any good?
I think that has to do more with the PFC than the BOV. It seems like nobody can get the PFC to idle perfectly, but with the ISC disabled, I think you should probably check for other possible problems like leaks or other PFC settings (fuel, timing)
In other words, I think "no" the BOV probably has nothing to do with a rough idle.
In other words, I think "no" the BOV probably has nothing to do with a rough idle.
Originally Posted by maxcooper
All BOVs (that I know of) use the boost pressure to stay shut under boost, since the pressure in the hose serves to cancel out the pressure in the IC pipe. Still, they can open under boost when the pressure drop between where the BOV is installed and where the hose connects to the manifold is large and overcomes the BOV spring. They are designed to open when the throttle closes, giving vacuum to the hose (since closing the throttle makes a vacuum in the manifold, even under boost) and pressure from the IC pipe side. They can open at idle, too, when the vacuum between the engine and the throttle overcomes the BOV spring. At idle, there isn't much happening (pressure or vacuum) on the IC pipe side. I am sure there are some minor design variations, but that's how BOVs work.
-Max
-Max
Well what I meant by that was this...The HKS sees the air and boost from the top of the valve rather than the bottom of it. So when your car is boosting it actually helps push the valve down on the seal.
The Tial sees boost from the bottom of the valve and does not help keep the valve shut on the seal the same way as the HKS.
IMO I'd still go with the Tial for looks and sound on my DD or weekend car. If I were serious about every performance aspect of the various BOV's, The HKS has proven to perform better.
Coyote
Joined: Nov 2004
Posts: 953
Likes: 0
From: Malta. Europe
ok, back on the spring pressure.... my BOV is set with an 11 psi spring. It sittin in the box, ready to get on..... but.... will the 11 psi spring cause any damage? ie wont open on vacuum?
Thanks
George
Thanks
George
NorCal 7's Co-founder
Joined: Aug 2002
Posts: 4,130
Likes: 5
From: Rocklin, CA
Originally Posted by tdazmansFD
Well what I meant by that was this...The HKS sees the air and boost from the top of the valve rather than the bottom of it. So when your car is boosting it actually helps push the valve down on the seal.
The Tial sees boost from the bottom of the valve and does not help keep the valve shut on the seal the same way as the HKS.
IMO I'd still go with the Tial for looks and sound on my DD or weekend car. If I were serious about every performance aspect of the various BOV's, The HKS has proven to perform better.
The Tial sees boost from the bottom of the valve and does not help keep the valve shut on the seal the same way as the HKS.
IMO I'd still go with the Tial for looks and sound on my DD or weekend car. If I were serious about every performance aspect of the various BOV's, The HKS has proven to perform better.
And to whoever corrected me about the spring pressure, I didn't word my original post right. The "rotary friendly" spring is good for us because as most all of you know our engines don't pull all that much vacuum. Especially once they're ported. That's why the softer spring is good for us.
Zach
I'm not way off here. I don't think you understand what I mean. Yes I agree with you about the vacuum lines purpose and such. I'm talking about the actual valve itself, and how it's located. Please, reread my post to better understand what I mean or, personally campare the two side by side as I did.
Coyote
Joined: Nov 2004
Posts: 953
Likes: 0
From: Malta. Europe
the way i see it for boost, the pressurised air + the spring pressure keep it close. you need a very soft spring so as soon as you pull vacumm, ie no boost, the spring is overcome and the cylinder is sucked up.
what i cant figue is that if your car, like mine idles at around 50KPA that about 7-8 psi, the valve will be open all the time and its leeking air like a bitch.... wont it start hunting due to opening and closing of air? i mean its gonna be like an idle bleed air valve mechanical though? i gather that i you have a 7 psi spring it will open and leak in air dust and all the crap into the engine, and at 11 it is shut, but then the vacuum is never strong enough to open the valve on throttle let offs.....please enlighten coz am lost!
George
what i cant figue is that if your car, like mine idles at around 50KPA that about 7-8 psi, the valve will be open all the time and its leeking air like a bitch.... wont it start hunting due to opening and closing of air? i mean its gonna be like an idle bleed air valve mechanical though? i gather that i you have a 7 psi spring it will open and leak in air dust and all the crap into the engine, and at 11 it is shut, but then the vacuum is never strong enough to open the valve on throttle let offs.....please enlighten coz am lost!
George
Last edited by signofinfinity; Feb 5, 2006 at 11:42 PM.
NorCal 7's Co-founder
Joined: Aug 2002
Posts: 4,130
Likes: 5
From: Rocklin, CA
tdazmansFD, maybe I'm just not getting what you are saying. I'll look at the two valves side by side this week.
Either way, this is a great BOV. That's probably why most of the more reputable shops recommend using it instead of other options out there. Not that the others are very high quality too. I'm really trying not to start any flame wars here.
Zach
Either way, this is a great BOV. That's probably why most of the more reputable shops recommend using it instead of other options out there. Not that the others are very high quality too. I'm really trying not to start any flame wars here.
Zach
Coyote
Joined: Nov 2004
Posts: 953
Likes: 0
From: Malta. Europe
far from it! i already have a Tial BOV.... But i was trying to figure out the required pressure. i idle round 7-8 psi vacuum........
George
ps... doh you are right about the idle air leak... it before the throttle body!
George
ps... doh you are right about the idle air leak... it before the throttle body!
Rotary Freak
Joined: Jan 2004
Posts: 2,116
Likes: 1
From: Northern California
Originally Posted by BoostedRex
The Tial is a GREAT BOV!! Just make sure that you get the "rotary friendly" spring from Tial. The standard spring is too hard for the boost levels that we run and you'll experience compressor surge if you aren't at WOT. One of the best built BOV's I've ever seen too. I love mine and would never switch to anything else.
Zach
Zach
Originally Posted by BoostedRex
tdazmansFD, maybe I'm just not getting what you are saying. I'll look at the two valves side by side this week.
Either way, this is a great BOV. That's probably why most of the more reputable shops recommend using it instead of other options out there. Not that the others are very high quality too. I'm really trying not to start any flame wars here.
Zach
Either way, this is a great BOV. That's probably why most of the more reputable shops recommend using it instead of other options out there. Not that the others are very high quality too. I'm really trying not to start any flame wars here.
Zach
It's hard for me to explain unless you're looking at the mechanics of the two. Don't worry I don't like getting involved in wars anyway. It always results in sitting pissed off in front of your PC with nothing you can do about it! haha.
I appreciate all that you've contributed to this forum and thought that this would be a good time to put my .02 into it.
And like I said before, I still prefer the Tial over anything else. D
