WILL the PFC control boost on a SINGLE TURBO
with a 3 bar Mapsensor??

Or do I need to get a seperate boost controler?

 

The PFC controls boost using the stock solenoids, which you will want to remove from the engine bay anyway. Just spend the $300 and get a boost controller.

 

Get the boost control kit or an aftermarket controller. Do not use the stock solenoid on an external wastegate.

 

Why can't you use the PFC with stock wastegate solenoid to control boost (10-14 psi) on an external wastegate?

 

I have the same question. Ryan, Spyfish have either of you tried to do this?

 

ditto.

 

Because the stock valve isn't strong or fast enough to control an external wastegate accurately, that's why APEXi sells a boost control kit for the PowerFC.

 

Plus there is no vent in the stock solenoid .....

 

If there was no vent on the wategate solenoid how would you raise boost on stock wastegate (8psi)? The stock solenoid vents into the primary turbo. The black plastic intake to the primary has two hoses pluged into it. One is for PCV and the other is dudy cycle discharge from the solenoid(s).

 

Well it is a 2 port solenoid instead of a 3 port. The only real way to use the 2 port sytem is with restrictor pill and a dual port wastegate. I can think of a way to run a 2 port but it would be hokey and the small port size would definately limit the speed .. if it worked at all.

 

I understand your reference to the stock system design, however the stock system is not much different than a manual boost controller. Both bleed pressure away to a given system to achieve a determined boost pressure. Each has its own design parameters to contend with. Likewise an external wastgate interfaced with the stock wastegate solenoid/PFC will need some experimentation/testing to work.

 

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I've seen the blitz and apexi solenoids and both have only two ports. What 3rd port are you referring to and what is its function?

 

If you have seen the Apex solenoid you know that it has 3 ports and 2 fittings. The other port is open with no fitting. That is where the air comes out when the solenoid is cycled.

 

Actually I saw an apexi solenoid today and it had two lines coming off it. I guess I need to ask you what a 'port' is and what a 'fitting' is.

 

^

 

2 lines equals 2 nipples

The nipples thread into the ports. Look at the picture of my boost control kit that is floating around. You can move one nipple from one port to another.

 

The solenoid that came with my AVC-R has 3 ports, but you only connect lines to two of them.

Manifold pressure goes to the NC (normally closed) port. Then you connect the COM (common) port to the top nipple on the external wastegate. You leave the NO (normally open) port on the solenoid open. You also connect manifold pressure to the side port on the wastegate, but that has nothing to do with the solenoid.

In the normal state of the solenoid, you get spring pressure. The manifold pressure at the side port on the wastegate opens it, and the top port is vented by the solenoid. The air in the top of the wastegate can escape by entering the COM port on the solenoid and exiting the solenoid through the NO port. The manifold pressure is also "dead ended" at the NC port on the solenoid.

When the solenoid is "active", air can flow through the solenoid by entering the NC port and exiting via the COM port. So, when the solenoid is active, the manifold pressure is routed to the top of the wastegate, holding it closed.

The boost controller senses the boost and cycles the solenoid to alternate manifold pressure or a vent to the top of the wastegate. It adjusts the duty cycle to maintain pressure in the top of the wastegate at just the right level so that you get the boost level you desire.

That is the normal setup for an aftermarket boost controller with an external wastegate. Raising the duty cycle raises the boost level.

The stock system in the FD uses a restrictor in the line that feeds manifold pressure to what is essentially like the side port on an external wastegate. There is no equivalent to the top port of an external wastegate. There is a vent solenoid that bleeds air from the wastegate actuator. So, pressure in the wastegate actuator is controlled by the rate at which the manifold pressure can feed it through the restrictor, and the rate at which the solenoid bleeds the air out. Again, raising the duty cycle of the solenoid raises the boost level.

I tried to use the stock solenoids with a PFC to control boost on an external wastegate, but it didn't work very well. It perhaps could be made to work okay, but I decided it probably wouldn't ever work that great, I didn't want to blow my engine trying to make it work, and I'd rather just get a boost controller (as much as I dislike adding another "box" to my system) and be done with it. I think I made the right choice. I might opt for the simpler Profec B if I did it again, though.

-Max