Can someone explain external WGs and EBCs to me?

[87_7MGTE]

I dont know if im retarded or missing something, but I just cant figure out how they work. At least I thought I did until I started looking at how to hook up external WGs to EBCs. What is the top port on the WG used for? What does it reference? What does the side port on the WG used for and what does it reference? It seems to me like the port on the top of the WG would do nothing, because all thats in that part is the spring. But in all the EBC diagrams I have been reading this afternoon, it says that the EBC solenoid hooks into that, which I dont understand.

Right now I have a profec b spec 2, and im thinking of getting an avc-r. would they both hook up the same? and if so, which vac lines go where?

Oh, also while on the topic of external WGs... everywhere I have read says that the higher the spring is rated for PSI, the weaker the spring is? Is that true? It seems like it should be exactly the opposite of that. It seems to me that the stiffer spring should allow more PSI? I dont get it, what did i get myself into. :1zhelp:

Thanks for the help.

 

[mattjk]

well you have the basic idea right. The second port can aid the spring in keeping the valve closed for higher boost. Also depends on the type of valve, whether is is a push closed or pull closed type. Which one do you have?

 

[87_7MGTE]

what do you mean by the 2nd port, the port on the top or the port on the side. I have an HKS replica (ebay) wastegate. i dont know if its a push closed or pull closed (i would assume push because the spring is pushing the valve down? i really dont know)

heres are 2 pics of it torn down:

everything that you see is what it came with.

 

[mattjk]

There are a couple of ways to control boost.

First, you hook up the side port to your compressor housing. (NO EBC). The spring strength determines how much the valve opens (amount of boost). The stronger the spring, the more boost you will have.

Now, depending on how you have your EBC configured, either swing valve or poppet, you can tap into the side port and bleed off pressure, OR you can hook up the EBC to the top port and send a pressure (cancellation) signal to effectively increase the spring pressure and get more boost pressure.

 

[mattjk]

I would use the second method myself. Have the side port connected to your compressor housing permanently, and configure your spring for how much boost you want to run daily, say 11psi for example. Then configure your EBC for poppet style and send the pressure signal to the top port.

BTW, careful NOT to send a vacuum signal to your WG, you'll end up damaging the diaphram.

Another thing, I noticed you are missing a couple of parts. The top of the WG, there is a threaded opening. You can install a bolt and jam nut, and a plate that fits on top of the spring. You can tighten down the bolt to increase the spring tension and raise boost that way without the use of a boost controller.

 

[87_7MGTE]

thank you mattjk for all your help, it really does help. in the center port on top of the WG, can i just put a bolt in there so that it is airtight? or do i need to put a bolt, jam nut and plate in there too. i will for sure be using a boost controller, so i wont be using WG at all to control boost. (well, i will, but you know what i mean.)

edit: also, which method do you recommend, or is more common for external WGs, swing valve or poppet? (i thought swing valve was an internal thing.)

 

[87_7MGTE]

oh and also, im assuming i can get any bolt that will thread in the top fitting and a nut that threads on that bolt from my hardware store? what about the plate, can i just use a big washer, or is the plate something special?

 

[87_7MGTE]

bump, anyone?