I've had nothing but fits over the years trying to get manual boost controllers to work consistently on moderate boost large displacement engines like ours. The problem is that restrict the initial opening of the gate, but once it opens, it STAYS open and loses boost with RPM. I spoke about it recently on the Power and Speed Podcast.

The real solution is either a two-port gate, with the boost controller acting on the other side of the diaphragm (without any internal check valve) or switching to an intelligent PWM based boost controller. The former requires new wastegates, plus the controller. The latter is more straight forward. I am in the process of switching over to the latter on my APS TT C6 using the Sirhc Labs Cortex controller. Cost is significantly less than an AMS2000, but has the ability to tie into the PCM for RPM and MPH to do boost by gear and closed loop boost control.

 

The Cortex controller is amazing for the money. I used it on my single turbo C6 and it was super easy to setup. I sold it since I am going the Holley route.

 

I think I'm going to give it a try and see what it does. I could always use an el cheapo compressor regulator to at least test the system.

Thanks Greg, I agree. Manuals have fought me too on LS stuff. I'm simply trying to walk before I run and wanted to confirm I can control boost with the setup before I drop $$$ on a real controller. I'll take a look at the Sirhc Labs Cortex. I wonder if thats the same controller that Kfxguy on here bought that did boost by gear via mph and stuff that he said he loved and was cheap. I think for a cheap next step is to A) try the diagram from that link and see how it reacts, or potentially just add more spring pressure which I have available and go from there.

 

Yup, that's the one. Only about $400

 

He had a write up it, seems pretty legit. That is actually the 1 I was thinking of buying once I sorted out the boost control with the throw away manual one.

 

I highly recommend it. It does have a few safety's you can configure; overboost and AFR cut to wastegate pressure. Boost by gear; RPM and speed, open loop or closed loop boost control. It can also control a water meth system or nitrous. Customer service is top notch. When ever I had a question, they answered within a few hours. It now has a scramble boost option.

 

I wouldnt mind having it add meth control too after my Alky Control debacle on the used kit.

 

If no signal to the gate yields low boost, and adding boost to top chamber gives you 16psi....how much boost do you want ?

If you want up to 16psi, then just plumb the manual bleed into the top chamber to blow the gate shut instead. The **** will work in reverse. Closed, full signal to the gate will give max boost, fully open will give lowest boost.

Simplez, free.

And where are you taking the signal reference from ?

IF...pre turbine pressure was very high, you could potentially use this pressure for the control to blow the gate shut harder.

 

i have a couple of those little regulators laying around if youre really feeling broke. i used that style with great success before i had my ams1000.
hell, before the ams1000 came out, everyone was building crazy 5 stage controllers with nitrous timers and solenoids that basically just routed through a bunch of those same regulators.

 

here you go, top shelf boost control circa 2005

 

Holy ****. haha

 

I would like to be able to walk up from 10 to 15 psi or so. I'm not against spending $$$ on a controller, I just want to makes sure I have CONTROL before spending the money to find out I have a different issue. Signal reference is from the intake manifold (yes yes should be pre-TB). I have a pretty good feeling that if I reroute the vacuum/controller to the dome then I should be able to increase the boost.

 

I am kinda shocked with a little 65mm turbine and only a single 38mm gate you only have 10PSI max, do you know what the wg spring is rated for? I would expect back pressure to be fairly high on that setup so Stevie's suggestion to hold the top port closed with boost pressure should help.

 

To blow the gate shut, you'll get a much higher signal from the compressor itself. As you're bound to have a huge pressure drop from the compressor to intake.

Do what I've said, it's free and easy to test ( apart from some hose )

 

Good grief were you trying to regulate down to 1 PSI and have multiple stages? I tried one of those regulator boost setups way back, but I ended up just running 25+ with a typical cheap boost controller. The physical controls for boost haven't changed much at all over the years, but the software controlling the solenoids has gotten much better.

 

Be a lot easier to use the ecu to do it though lol.

 

I don't know what the spring is rated for, which is the other reason why I suggested adding dome pressure via the manual controller and asked for feedback. Should help keep the gate stay closed and hit more boost. Otherwise I just have an excuse to go to a billet 7875

But a compressor reference will also open the gate sooner due to losses in the FMIC and piping, which is why I was running it from the intake. I guess if I'm just trying to add a bunch of dome pressure I could just try it off the compressor for shiggles.

 

That would be impossible if you do it the way I said. Hence why I said how to do it lol.

 

haha hmm I know a guy. Ya if you aren't using it to open the gate, only hold it closed the losses shouldn't matter.

 

man, i wouldnt have run a vacuum line all the way from the front. just pull from the turbo outlet. its all relative anyway, the wg doesn't need to see what your intake sees it just needs a positive pressure source and something to control it.