Twin scroll wastegate setup

[Gstclipse69]

I am installing 2 tial mvs 38 gates on my twin scroll t3 manifold. I searched a good bit and saw nothing pertaining to running the vacuum lines to the wastegates. I am assuming that I will run a line from my boost source on the compressor cover to my boost controller. Then run my line from the boost controller to a Tee fitting and run the lines from the Tee to each port on the separate wastegates. Am in correct in my thinking or is the Tee fitting going to mess up the pressure that the two wastegates see?

 

[crimsondragon]

Correct. Use the ports on the side of the WGs not the top port. Do you have an idea of the target boost you want to hit? It would be even easier to just connect the WGs directly to a boost source and run it off of spring pressure.

 

[Gstclipse69]

Awesome, yea I'll use the side port, the top port is supposed to be left open correct? Target boost will eventually be around 30 psi. I will probably run it off spring pressure to start with, 22 psi, get the tune dialed in, and then turn it up from there. I dont think spring pressure alone will allow me to run 30 psi correct?

 

[crimsondragon]

Nope, it looks like for the MVS the max pressure the spring combo will hold is ~25psi.

 

[Gstclipse69]

Ok, I have a problem with the wastegate setup. To be completely clear I have a Redjack racing twin scroll manifold with two tial mvs gates on it mated to a 7 blade hx35 with its stock 12cm t3 housing. First off I just had the boost source off of the compressor housing running to a tee then to the side ports on either wastegate just to run it off the spring pressure first. That worked. The springs were supposed to put me at 22 psi or so, and I observed about 23 psi on several pulls.

Now, I go to put my boost controller in line, which is just a plain jane nxs boost controller that worked fine with my 18g. I put the boost source to the bottom of the bc and the other line that runs to the tee on the opposing side port of the bc. Now I have tried adjusting the boost controller almost from one end of its spectrum to the other and the boost just skyrockets with no control over it. The boost will slowly onset to about 10psi, then somewhere about 12-15 psi it just jumps to over 30 psi in a 1/4 of a second. It spools incredibly fast.

My vacuum lines are as short as possible as well. The line from the compressor cover to the bc is like 3 inches, then the line to the tee from the bc is like 8 inches, then about 4 inches to each port on the wastegates. If this has anything to do with it, my boost gauge is tee'd into my fp solenoid line and its a manual gauge. I dont know if the tee is messing it up or I need a different boost controller or two boost controllers or what. Any advice would be great, and if you have twin wastegates, please post up your vacuum/bc setup. Thanks, Chris

 

[SHEARER_TSI]

are you sure the boost controller is hooked up correctly?

 

[Gstclipse69]

Yes Im positive.

 

[snowborder714]

Do you happen to know anyone who has a different boost controller you could try - possibly a Hallman? The NXS just looks like a homemade boost controller, which have been proven to to be the most reliable.

 

[Gstclipse69]

Not really, Im pretty much a solo dsmer. I guess I will see if I can pick a hallman up or something. Does the rest of the setup sound right with the vacuum lines and all? I've tried google searching and everything and I really cant find much of anything pertaining to setting up dual gates.

 

[5150DSM]

Sounds like you have the gates and the b/c set-up right. I've found the NXS b/c's to be a little twitchy, I've had three now and they all had regulation issues to some degree. It seems that they have a "sweet spot" where they regulate just right, a couple psi above or below and my boost would jump around, sometimes high, sometimes low. I don't know if this is a spring weight vs. ball weight issue or maybe the bleeder not being cut evenly all the way through the tee. Regardless, I've had similar issues with the NXS controllers. If you can, swap it out and recheck the performance, if it does the same thing then look elsewhere for your issue.

 

[Gstclipse69]

Thanks for the advice and verifying my setup. I am currently looking at the hallman's now. Specifically the rx with the ceramic ball and heavier spring. Does anyone know how much boost the hallmans are good for? Im trying to be up around 30 psi or maybe a tad more. It didnt say on their website faq.

 

[fosforito95]

im also interested in the dual wastegate config so keep us updated to see if that solves your problem

 

[snowborder714]

The Hallman will work fine for that boost level. I've run 25 on mine before without any issues, and am sure people on here have pushed over 30.

 

[crash89]

I have almost the exact set up as you and wanted to share how I have my boost controller hooked up.. Redjack t/s manifold with dual 38mm gates, hx35 and Hallman bc.. Bottom of the controller is hooked to the boost source, side port of the controller goes to the Tee which goes to the side ports on the waste gates, top ports are open..

sorry for the quality of the pic, I just went out and snapped a quick picture for you.
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[Gstclipse69]

Thanks a lot guys! Crash thanks for the pic. Thats pretty much exactly what Im working with too. Im gonna get the hallman on the way tonight.

 

[Gstclipse69]

Update: I now have boost control with the Hallman. I got a Pro Rx with the ceramic ball and I installed the heavy spring. At first I thought since I was running spring pressure at 23 psi, I would go ahead and set that sucker in about 1/2 way. That didnt work, it just skyrocketed like it was doing before. Then I backed it up to 2 turns in from the top. First pull was at 25 psi. AWESOME Then I turned it a 1/2 turn more and 26 psi on the next pull. Then one complete turn and the boost stayed the same about. Another 1/2 turn and shes sitting at 28 psi right now. I didnt have the means to make a complete pull to datalog and check my tune, but I will shortly. So problem solved. I guess I got my moneys worth out of the Nsx bc though.

Do any of you guys run 4an stainless lines to the bc or have problems with the vacuum lines melting? My lines are like right up against the radiator, and about 1/2" away from the manifold. And there isnt really anything I can do about it as far as moving them.

 

[snowborder714]

You could just put some of the reflective heat tape on the lines, or use a heat sleeve like you would on an oil line. Stainless would be nice, but a bit pricy.

Glad to hear the new MBC fixed the issue.

 

[bradikus7]

Rather than creating my own new thread, I'd like to bring this one back. I'm in the process of configuring my dual WG's and am trying to get a visual. Now I'm currently running a single with my AEM Tru boost controller. Anyone know how I would go about setting this up for duals on my particular controller? Thanks in advance.

 

[Devilsfutbol17]

Would you not just use a T-fitting for the additional wastegate? The output of the boost controller would go to the T-fitting, then the two wastegates would also be connected to the T fitting. That is how I have my dual wastegates setup.

 

[bradikus7]

Found this picture searching google, not for our cars but I don't know why it should be any different? Can anyone confirm if this is correct?

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Would you not just use a T-fitting for the additional wastegate? The output of the boost controller would go to the T-fitting, then the two wastegates would also be connected to the T fitting. That is how I have my dual wastegates setup.

I was thinking this too.

 

[dmaffo]

Does the image above work? I have 2 tial 44 and wanted to make sure that works. Wasn't sure if a simple "t" split would do the trick. That I guess is my main question. On a twinscroll set up that is.

 

[LandSpeed-DSM]

I have mine plumbed individually from a vacuum block, but a T will work fine.