Jack

iTrader: (2)

I am presently controlling boost with just the wastegate spring (HKS 50mm) aprox 12psi. I am running a TO4E and even though the turbo spools quick, I know the "spring only" is slowing my boost curve. I decided to tee the wastegate solenoid from the stock sytem and control boost duty cycles from my PFC. Basicly a bleed to atmoshere, this system has sharpened the boost rise and has only raised the max boost to 12 1/2- 13psi. My next idea was to run a line from output of the stock solenoid which prior was bleeding to atmoshere, to the top of the wastegate. The idea was to control boost with differential pressure, again controlling boost duty cycles with commander. Has anyone tried this? comments are welcome.

maxcooper

I tried it, had limited success (quick rise to 15 psi, but dropped to 12 psi by 7000RPM), but wasn't satisfied and switched to an AVC-R.

I think it might work with a little more development time. You basically need to have the line to the top of the wastegate vented (to the atmosphere, so the pressure can bleed off) OR pressurized, and use the solenoid to switch (duty cycle) between these two states. For a 2-position, 2-way solenoid (basically an air switch), you can't really do that, so one approach is to install a vent with a tuned size in the line between the solenoid and the top of the wastegate. I don't mean to put a pill IN the line, but rather to install a T in the line, and then connect a third line with a pill in it that vents to atmosphere. You want the vent big enough to bleed off pressure when the solenoid in non-passing, but not so big that you can't build pressure in the top of the wastegate when the solenoid is passing. Using both stock solenoids wired (and plumbed) in parallel would support more flow if that proves to be a limiting factor.

-Max