SirCygnus

iTrader: (1)

as the title states, im wondering how many people in this section just run a manual boost controller setup.

i hear people talk about the profec unit tons, but nothing on MBC's

arghx

iTrader: (3)

I used to run one on my HKS external gate. They do get the job done, but they fluctuate more with the weather and are harder to set precisely IMO. They also don't let you push the wastegate closed using the top port of the gate. I ultimately decided to have my Power FC control boost so I could log the solenoid duty cycle and so I wouldn't have a separate external box with extra wires and plumbing.

Aren't you running a Haltech?

SirCygnus

iTrader: (1)

yes

e6x

arghx

iTrader: (3)

Why don't you just control boost off the Haltech? Even if you don't use the closed loop settings (because they have a significant learning curve), the open loop boost control is just like buying an AEM Tru Boost. Grab an FD wastegate solenoid (or FC boost control solenoid) with connector pigtail. I've got an FD solenoid and pigtail lying around if you need it. One wire gets hooked to the PWM output of the Haltech and the other gets +12V ignition power. Hook it up like this, using NPT fittings to vent pressure from the top port:



Make sure the Haltech is set to 30hz for the boost control solenoid frequency. Scale the MAP columns appropriately. Then set every cell in your open loop map to the same value and log your peak boost/boost curve. Your solenoid is now running a fixed duty value, just like the "duty" setting on the AEM Tru Boost does or the "SET" in a Profec B Spec II (minus the Greddy's gain control). This screenshot will give you an idea of what I'm talking about:



Then you raise the duty cycle across the board again and record the boost levels. Start with something like 30% and progressively increase the value until you reach your target boost (it will fall off some). It's the same procedure as tuning an AEM Tru Boost.



Then to improve spool, start setting the low MAP area to a duty of about 95%. This effectively shuts your wastegate by applying pressure to the top port of the gate. This is the same as tuning "START BOOST" in the Greddy Profec Spec II or "Spring" in the AEM Tru Boost.



So first have it run 95% duty up to about 4psi, after which you can taper the duty down to the duty value you used before (say 50%).



Then you can have it run 95% duty up to 7, then 10psi, or however high you can get it without a major spike. This is the same procedure used in tuning any other EBC really. They all work the same way. The difference here is that you are going completely open loop. It's a lot better than an MBC, but doesn't have the learning curve of setting closed loop gains. WIthout closed loop gain (which you could enable later) there will be some taper of boost up top (just like other open loop controllers such as the AEM Tru Boost).

Since you already have boost control capability in your standalone, why not use it? The plumbing is the same basic setup as any other EBC, the wiring is simple, the solenoid is cheap, and the tuning is not much different than an external EBC.

SirCygnus

iTrader: (1)

interesting indeed!

shoot mje a pm for the infor on the whatsithoosits.

arghx

iTrader: (3)

that's similar to the setup I'm running on my Power FC, except the duty cycle adjustments are rather crude in the PFC

arghx

iTrader: (3)

that's how I have the FD solenoid mounted on my 2nd gen, it's screwed into some bolt hole on the strut tower. Note that I have the solenoid mounted upside down. In the diagram I posted earlier, the connector is at the top. You can see I have it flipped over so the connector is at the bottom, and thus the inlet and outlet to the solenoid are reversed.

FD3S_wanted

iTrader: (5)

Nice.

Do you know if I can do the same with a E6K?

arghx

iTrader: (3)

I don't know a whole lot about the E6K. If it has an open PWM output and boost control tables I would think it should work fine for open loop electronic boost control.

zinx

iTrader: (3)

The E6k does have the ability to control boost but everything i've read say not to even mess with it as its terrible at it. So, i've not actually done it. There are some old threads in the haltech section about it.

arghx

iTrader: (3)

I've never personally done boost control on a Haltech. But I've done it on a Power FC, and I am very familiar with the way Subarus do it from the factory. Subarus and other OEM controllers are pretty much a highly advanced version of Haltech boost control. They have basic open loop duty cycle tables, air temperature and rpm correction tables on top of that, and then closed loop target and gain tables for self-adjustment. The AEM EMS is the same way. A boost controller is only as good as its mechanical system and tuning.

People who say "don't do boost control on a standalone" are either arguing for the simplicity of separate controllers or they just don't fully understand how boost controllers truly work. If the computer (Haltech etc) cycles the solenoid at the duty you tell it to and at the frequency you specify, there's nothing wrong with the computer. If you don't know how to use a duty cycle map to control boost, that's not the computer's fault. It's the whole garbage in, garbage out deal. People also say the AVC-R is difficult to tune, but the AVC-R is the closest to the Haltech/AEM EMS/OEM systems as you can get in a separate box.

And ppen loop boost control is as simple as you can get, and it is also the method employed by the AEM Tru Boost external controller. If you have it plumbed right, you just keep increasing the solenoid duty and watch the boost increase, then make finer adjustments to improve spool. Now, at the risk of pic bombing this thread...















yes I know that was probably too much to post. But again I am just trying to illustrate that boost control systems all work the same with only slight variations (stepper type for example). Either the solenoid turns on or it stays off. When and how long that happens, as well as the final result, are up to the user ultimately.