TT , twin waste gates, Greddy profec oled boost controller help!!!
Yeah the 479 made no sense...my haltech reading is under 1.00 typically
your BOV opens in that condition. Its vac line is Post TB and works like a wastegate as well. the 15psi will open the BOV and relieve itself.
your BOV opens in that condition. Its vac line is Post TB and works like a wastegate as well. the 15psi will open the BOV and relieve itself.
Even worse. And I'm not concerned about pre TB pressure. It's about turbo overspin, because your target boost signal is taken at wrong place. Turbo will be forced to overspin because it will never get the "boost target".
why would it overspin? That 15psi will also open your wastegates (depending on spring setting) and since your boost controller should be fed from post TB, it will have 0 boost to help keep the WG shut...even at 100% dc on the boost solenoid valve.
I don't think your scenario is possible for extended amounts of time....its a transient state.
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Joined: Feb 2012
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From: Canada eh
Reading this making me think twice about my current setup. The bottom nipple on my waste gate is connected to the vacuum/boost source on the plenum which is after TB. What difference is it going to make if i connect it before TB?
Define bottom and top nipple?
I would think it'd make a big difference ...
if you are about to shift at 6000 rpm and youre at 14psi of boost and your TB shuts, your charge pipes (for a brief second until the bov opens) are pressurized while while your plenum is in vacuum - where do you want pressure and where do you want vacuum at that moment when you shift in your waste gates?
I would think you'd want pressure pushing open simultaneously while vacuum pulling open the waste gates to allow exhaust to bypass your turbine? This is how I understand it...
I would think it'd make a big difference ...
if you are about to shift at 6000 rpm and youre at 14psi of boost and your TB shuts, your charge pipes (for a brief second until the bov opens) are pressurized while while your plenum is in vacuum - where do you want pressure and where do you want vacuum at that moment when you shift in your waste gates?
I would think you'd want pressure pushing open simultaneously while vacuum pulling open the waste gates to allow exhaust to bypass your turbine? This is how I understand it...
Last edited by bealljk; Mar 15, 2017 at 09:56 PM.
New Member
Joined: Feb 2012
Posts: 193
Likes: 8
From: Canada eh
Define bottom and top nipple?
I would think it'd make a big difference ...
if you are about to shift at 6000 rpm and youre at 14psi of boost and your TB shuts, your charge pipes (for a brief second until the bov opens) are pressurized while while your plenum is in vacuum - where do you want pressure and where do you want vacuum at that moment when you shift in your waste gates?
I would think you'd want pressure pushing open simultaneously while vacuum pulling open the waste gates to allow exhaust to bypass your turbine? This is how I understand it...
I would think it'd make a big difference ...
if you are about to shift at 6000 rpm and youre at 14psi of boost and your TB shuts, your charge pipes (for a brief second until the bov opens) are pressurized while while your plenum is in vacuum - where do you want pressure and where do you want vacuum at that moment when you shift in your waste gates?
I would think you'd want pressure pushing open simultaneously while vacuum pulling open the waste gates to allow exhaust to bypass your turbine? This is how I understand it...
Top is top, bottom is bottom LOL
Top is what connects to boost controller, bottom is what connects to manifold pressure as far as I know. I went by the instructions with the turbo kit and boost controller.
I do see your point though, you might be right. I'm gonna try to redo mine and see if it makes any difference. The sound the car makes when I let off throttle does sound a bit like compressor surge, so this might be a fix. Took it to few shops and they said its normal.
Turbo kit
Boost controller
POST tb is for the boost solenoid/map sensor.
Pre TB is for the bottom of the WG so that they open up while the bov is venting the charge pipes.
Bottom/Top port is relative to the actuator head vs the valve body, not in how it is mounted on your car. It is a poppet valve with spring assist closure.
