Adam Kindness Posted June 26, 2002 Share Posted June 26, 2002 going by the tech articles on mkiv... i disconected hose two in the diagram below.... thinking it would have the same effect as fitting a t-piece with no valve... BUT - i got no gains in boost pressure at all! something up? Link to comment Share on other sites More sharing options...
Adam Kindness Posted June 26, 2002 Author Share Posted June 26, 2002 heres the link to the tech article > http://www.mkiv.com/techarticles/bleedert/bleedert.htm Link to comment Share on other sites More sharing options...
THOR Racing Posted June 27, 2002 Share Posted June 27, 2002 You want to control the air flow in the pipe that goes from the output of the turbo bleed nipple (at the very top of the turbo housing) down to the top of the wastegate actuator. The pipe from the second (lower port) of the wastegate actuator is normally capped off. Or a much simpler thing to do is disconnect the VSV it attaches to. This closes the VSV and blocks it for you. However, I know when my cap or blocked pipe blows off the second port of the wastegate actuator that the boost skyrockets. So the fact you got nothing is strange. Could be the actuator isn't functioning properly? Try fitting the bleeder in the first pipe from the turbo bleed nipple to the wastegate actuator top pipe and see what happens then. Also I wouldn't recommend just leaving the pipe permenantly open, fit a valve. One spirited test of the boost may be the turbos last. Pete Link to comment Share on other sites More sharing options...
Ian C Posted June 27, 2002 Share Posted June 27, 2002 Why cap off the exit port from the wastegate actuator? I thought as stock the VSV stays open, making sure no pressure can build in the actuator, thus keeping the wastegate closed, until a certain boost pressure had been acheived and then it shuts. With a second control solenoid in place (i.e. an aftermarket boost controller), in the place you describe, that just stops any pressure getting to the actuator in the first place, until it's set boost pressure is acheived, and then it opens. The stock VSV is already shut at this point, so the wastegate opens. Leaving the stock VSV plumbed in allows the built up pressure in the system a return path to the induction side of things without trying to backfeed through the #1 compressor. So why take the stock wastegate VSV system out of the loop? Or have I missed something? -Ian Link to comment Share on other sites More sharing options...
THOR Racing Posted June 27, 2002 Share Posted June 27, 2002 With a second control solenoid in place (i.e. an aftermarket boost controller), in the place you describe, that just stops any pressure getting to the actuator in the first place, until it's set boost pressure is acheived, and then it opens. Umm. Not quite. An electronic boost controller (generally) doesn't just open and close at a set pressure. It pulse width modulates so that the resultant pressure is lower. It has three ports. In, Out1 and Out2. Out2 is atmosphere and In and Out1 are connected in series with the exisiting pipe. By increasing the time spent connecting the common port In to Out2 the more pressure is bled off to Atmos' and the less reaches (on average) the actuator via Out1. The electronic controller then dynamically controls the pulse width and modulates the solenoid valve according to the measured pressure at the manifold. Most instructions I've seen for boost controllers tell you to cap off the exit port of the wastegate actuator, but I believe (like you) that there is not much point in doing this. I was saying not to bother as the VSV will cap this off anyway. Maybe I didn't say that right before. I'm agreeing with you. BUT. I didn't find as good a control (personally) by controlling the exit port to the actuator as I did the input port. (in series with the pipe to the turbo bleed) Plus I've now removed the stock VSV as that's where my boost controller solenoid is mounted. Nice and close to the actuator and very short lengths of pipe. Pete Link to comment Share on other sites More sharing options...
Ian C Posted June 27, 2002 Share Posted June 27, 2002 Ahhh - I didn't know that about pulse width modulation of the aftermarket boost controller solenoid. Mine is plumbed in to the turbo housing to wastegate actuator line as well, but the rest is as stock, so I wasn't contending that point. You did actually say that the wastegate VSV should be disconnected, but mine is still wired up and everything seems to be normal. But then it boosts to 1.2bar with the boost controller set to 'off' anyway, and I don't currently go above this! Do you think short lengths of pipes make a difference? Mine aren't the shortest they could possibly be by quite a stretch... And it's something I can tidy up without having to spend money -Ian Link to comment Share on other sites More sharing options...
THOR Racing Posted June 27, 2002 Share Posted June 27, 2002 I did notice a hunting type effect (overboosting) on the electronic controller when I had mine originally fitted to the suspension strut. As there was pretty much no where else to put it (due to lack of room) I decided to remove the stock VSV and mount using the same holes. This improved things. But then the pipes went from around 0.8m to about 0.1m so quite a change. Put it this way. If you do it, it's costs you nothing and may improve controllability. Or it may not, but then you've just made it neater. Can't loose I guess. Pete Link to comment Share on other sites More sharing options...
Doughie Posted June 27, 2002 Share Posted June 27, 2002 Originally posted by Adam Kindness going by the tech articles on mkiv... i disconected hose two in the diagram below.... thinking it would have the same effect as fitting a t-piece with no valve... BUT - i got no gains in boost pressure at all! something up? Adam I fitted a bleed valve to my mkiv myself and it worked great right away. I opened up the valve half a turn, went for a blat, and did that 2 or 3 times until i got the boost level i wanted in 4th or 5th gear. I too used that same piccie that you posted from mkiv.com as a guide but i don't think that the picture is very clear. If Keith has a moment, maybe he could take a digi piccie of the bleed valve in my car (sorry - his car..) and that might help. (in case you got the wrong hose or something). Personally i think bleed valves are great, simple, easy and cheap. And entirely reversible should you want to sell the car or fit an EBC. Also, a lot less "noticeable" than an EBC should you have a prang.... Link to comment Share on other sites More sharing options...
Adam Kindness Posted June 27, 2002 Author Share Posted June 27, 2002 Ohhh Keith !!! Link to comment Share on other sites More sharing options...
piehound Posted February 22, 2006 Share Posted February 22, 2006 sorry to bring up an old thread but as anyone actually got a pic of a manual bleed valve in situ so i can plumb mine in the same, i cant seem to follow some of these pics and info about cutting here and there, i need a pic of the t piece in place showing where it goes and what else needs diconnecting etc damn thing it was simple on my nissan with pics Link to comment Share on other sites More sharing options...
ardasaliah Posted February 22, 2006 Share Posted February 22, 2006 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=13234 Bleeder goes on the pipe that the red arrow points to. Bottom nipple! Just cut that pipe in half. Put your bleeder in. Thats it. Half a turn= about 0.1 bars worth of extra boost. Be careful! If you are using a ball and spring type manual boost controller then it goes on the nipple above the red arrow. Link to comment Share on other sites More sharing options...
piehound Posted February 22, 2006 Share Posted February 22, 2006 i dont quite understand the sketch i asume where the arrow point there is another hose this is the 1 i cut then it is a manual bleed valve it looks like the 1 you have drawn ill take a peep when it arrives 1 more question , the max boost i want to see is ????? thanks Link to comment Share on other sites More sharing options...
ardasaliah Posted February 22, 2006 Share Posted February 22, 2006 yep thats the one. Have you got your cats in? If you have -don't raise it more that 0.9bar. Link to comment Share on other sites More sharing options...
piehound Posted February 22, 2006 Share Posted February 22, 2006 ive hopefully got decat pipe sorted im just waiting on confirmation Link to comment Share on other sites More sharing options...
piehound Posted February 23, 2006 Share Posted February 23, 2006 well the mbc landed today and guess what i got the wrong 1 lol i looked at 2 on ebay and the 1 i got isnt the 1 with the spring and ball in it so i guess it wont work its more of a open a bit and the air passses through it kind of valve grrrrrrrrrr unless someone knows if it will be ok ??? Link to comment Share on other sites More sharing options...
ardasaliah Posted February 23, 2006 Share Posted February 23, 2006 Mine is not a ball and spring either. its just a bleed valve. works a treat!!!! Seriously its fine. Had mine on now for over a year- running just a little over stock- 0.1bar more. Its fine. mine looks like this. just cut the pipe and put the two silver ends on to each end of the cut pipe. make sure its secure. bleed air out- to increase boost. NOT TO MUCH!! and remeber this is just advise-so I can't be responsible for anything that happens as a result of increasing boost. HAD TO SAY THAT. LOL http://www.abbottracing.com/2002/images/tuning/apc_bleed_valve.jpg Link to comment Share on other sites More sharing options...
piehound Posted February 27, 2006 Share Posted February 27, 2006 hey thats the same valve i got so i just cut the hose to the actuator(the red 1) and shove it in there Link to comment Share on other sites More sharing options...
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