guyz Posted April 22, 2019 Share Posted April 22, 2019 TRADER FEEDBACK 0 0 0 TOTAL RATING N/A Members 0 4 posts Locationvancouver bc Report post Posted 6 hours ago Based on old but positive posts on here, I recently bought a HDI electronic boost controller (type D) and am ready to install it. Seems great but I'm not super impressed with the instructional clarity regarding running the pressure lines to/from the solenoid. I'm running an external wastegate and it's clear and obvious that the pressure signal from my compressor outlet goes to port P on the solenoid. Port A then goes to the wastegate and it seems to make sense that it should go to the chamber below the diaphragm and spring, solenoid sends pressure signal at set boost ceiling and the wastegate is opened, thereby doing its job. The waters are cloudy for me when I go to the expanded schematic on page 9 of the online install manual (www.hdimenu.com) where it shows the solenoid output (port A) going to the upper chamber of the wastegate (spring side). They then show a line connected from the WG lower chamber, below the spring/diaphragm that is being fed by manifold pressure. What that means to me is that when boosting there is essentially an equilibrium of pressures coming at the diaphragm from either side. As I write this it is starting to make sense to me that once the solenoid is triggered by the preset within the controller, it opens and the pressure that is pushing against the top side of the diaphragm and holding the WG closed, then bleeds off via the open and unused solenoid port R, and the WG will then be free to open because of the manifold pressure being exerted against the single, low side of the WG diaphragm chamber. If I've got this correct then some validation from those more experienced here will allow me to carry on accordingly. Thanks in advance Quote Link to comment Share on other sites More sharing options...
Nigel Posted April 23, 2019 Share Posted April 23, 2019 23 hours ago, guyz said: TRADER FEEDBACK 0 0 0 TOTAL RATING N/A Members 0 4 posts Locationvancouver bc Report post Posted 6 hours ago The waters are cloudy for me when I go to the expanded schematic on page 9 of the online install manual (www.hdimenu.com) where it shows the solenoid output (port A) going to the upper chamber of the wastegate (spring side). They then show a line connected from the WG lower chamber, below the spring/diaphragm that is being fed by manifold pressure. What that means to me is that when boosting there is essentially an equilibrium of pressures coming at the diaphragm from either side. As I write this it is starting to make sense to me that once the solenoid is triggered by the preset within the controller, it opens and the pressure that is pushing against the top side of the diaphragm and holding the WG closed, then bleeds off via the open and unused solenoid port R, and the WG will then be free to open because of the manifold pressure being exerted against the single, low side of the WG diaphragm chamber. If I've got this correct then some validation from those more experienced here will allow me to carry on accordingly. Thanks in advance Glad to see my review is being helpful. I'm still running my HDi boost controller all these years later, and it's never given me any grief. Yes, your interpretation is correct. Here's a couple of pictures that will hopefully explain it better... Quote Link to comment Share on other sites More sharing options...
guyz Posted April 24, 2019 Author Share Posted April 24, 2019 Thank you very much Nigel. I now understand how it works. The only thing I'm not 100% certain on are the solenoid ports to use If i blow into port P which is where compressor charge feeds into, that air bleeds thru the side port, if I plug the side port then no pressure gets past the solenoid to port A, which should go to the WG. This leads me to think that the WG should be fed by the side port and not port A. When I apply 12volts to the solenoid, it opens and allows the flow to exit the solenoid via port A(if side port is plugged) This would allow the WG to stay closed, if the solenoid is powered/engaged/open when wired with the controller and would allow the WG to open and spill pressure when the controller hits its preset and then cuts power to the solenoid, thereby allowing it to close and vent out the side port. I hate to seem like I'm belaboring this but I feel like I'm kind of rolling the dice on this part of the install and I don't think that's a great idea. Quote Link to comment Share on other sites More sharing options...
Nigel Posted April 24, 2019 Share Posted April 24, 2019 9 hours ago, guyz said: Thank you very much Nigel. I now understand how it works. The only thing I'm not 100% certain on are the solenoid ports to use If i blow into port P which is where compressor charge feeds into, that air bleeds thru the side port, if I plug the side port then no pressure gets past the solenoid to port A, which should go to the WG. This leads me to think that the WG should be fed by the side port and not port A. When I apply 12volts to the solenoid, it opens and allows the flow to exit the solenoid via port A(if side port is plugged) This would allow the WG to stay closed, if the solenoid is powered/engaged/open when wired with the controller and would allow the WG to open and spill pressure when the controller hits its preset and then cuts power to the solenoid, thereby allowing it to close and vent out the side port. I hate to seem like I'm belaboring this but I feel like I'm kind of rolling the dice on this part of the install and I don't think that's a great idea. I don’t have my Mac solenoid in front of me, but assuming it matches the pictures I found online, the ports on the solenoid are labeled with numbers. Looking at the nameplate side of the solenoid, the ports are numbered 2, 3, 1 from left to right, with port 3 being under the nameplate. This translates into the following labeling in the HDi manual: 1: P 2: A 3: R For your application (external WG), the solenoid will be connected exactly as shown on page 9 of the HDi manual. So, port 1(P) will connect to the turbo, and port 2(A) will be connected the upper port on the WG. Port 3(R) is left open. Note that the drawing in the manual could be misinterpreted and read as port 3 being the “P” port, since the arrow does somewhat look like it’s pointing at port 3 (the middle port). Perhaps that’s the source of your confusion, because you said that when you blew into the “P” port when the solenoid was de-energized, it was venting out a side port? If you are blowing into the actual P port (port 1) when de-energized, 1(P) is blocked with no airflow possible, and 2(A) to 3(R) is open. When energized, 3(R) is blocked and 2(A) to 1(P) is open. In operation, this means that when the solenoid is energized, boost pressure passes through port 1(P) to port 2(A), applying boost pressure to the top side of the WG and preventing it from opening, which is how boost greater than the WG spring pressure is achieved. When de-energized, the upper port on the WG is vented to atmosphere from port 2(A) to port 3(R), allowing the WG to open. By rapidly shuttling between these two states, boost pressure above the WG spring can be controlled. As a failsafe, since the de-energized state of the solenoid leaves the upper port on the WG vented to atmosphere (2(A) to 3(R)), the WG spring will then control the boost level, should the solenoid loose power for whatever reason. Quote Link to comment Share on other sites More sharing options...
guyz Posted April 27, 2019 Author Share Posted April 27, 2019 Thank you so much, it's all clear now, and I presume I can T off the line coming from the comp housing, prior to the solenoid inlet and send that line from the T to the low side of the WG. Sound good? Can't emphasize enough how much I appreciate your taking the time to steer me right. Can't wait to see how the new CX gt3071, dual ball bearing/billet wheel turbo works with my newly built 3" dp and plumbed wastegate. Cheers Nigel Quote Link to comment Share on other sites More sharing options...
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