Ok thinking of ECU controlled boost
[QUOTE=Mr. Evo IX;5751079]Actually you don't have to use the JDM map to use an aftermarket solenoid with the stock ECU..[QUOTE/]
I was justr saying that it helps by logging the boost very accurately. And depending on which method you use to control boost. load vs psi. I would rather control it by psi, IMO.
I was justr saying that it helps by logging the boost very accurately. And depending on which method you use to control boost. load vs psi. I would rather control it by psi, IMO.
I keep preaching it, but little listen... to say goodbye to the boost overshoot problems, just zero out the "Max Total Upward WGDC Correction vs TPS" table and tune the "Turbo Boost Error Correction" correctly. (as in add back in all the additive correction and then some, so that it actually brings back boost to target BWGDC in an event of boost being pulled)
Trust me, it's a *huge* piece of progress in the ecu-boost puzzle.
Trust me, it's a *huge* piece of progress in the ecu-boost puzzle.
post edited, trying to get foot out of mouth
.
Last edited by Mr. Evo IX; Jun 8, 2008 at 03:08 PM.
Evolving Member
Joined: Dec 2007
Posts: 126
Likes: 0
From: MA
i have some questions...
what i would like to do is switch from my current setup which is an in-cabin hallman, to Ecu controlled boost,
now i wanted to get a perrin BCS and it says to remove all restrictors, now every write-up i have read requires the restrictors pills, so i wanted to ask has anyone had any experience with this solenoid and i wanted to know how much can the stock ecu compensate for weather and such
i know that alot of EBC's solve for weather, cause it can get very cold at night around me and then very hot in the day...is the ecu method set and forget and it will make the set PSI happen like an EBC or no
sorry if these r a little redundent, i usually stick to MBC's when i tune, this would be my first venture into EBC
what i would like to do is switch from my current setup which is an in-cabin hallman, to Ecu controlled boost,
now i wanted to get a perrin BCS and it says to remove all restrictors, now every write-up i have read requires the restrictors pills, so i wanted to ask has anyone had any experience with this solenoid and i wanted to know how much can the stock ecu compensate for weather and such
i know that alot of EBC's solve for weather, cause it can get very cold at night around me and then very hot in the day...is the ecu method set and forget and it will make the set PSI happen like an EBC or no
sorry if these r a little redundent, i usually stick to MBC's when i tune, this would be my first venture into EBC
Last edited by No.9; Jun 8, 2008 at 08:26 PM.
What the others are saying is true ... the stock solenoid is fairly good with the right restrictor/bleed in place. I ran 26 psi on the stock solenoid and had no problems.
About the Perrin solenoid though ... yes. you just connect it to the stock harness (I used vampire taps) and then tune. Simple as pie ... or pie with a pre-made filling at least.
About the stock vs 3-port debate ... this is my opinion. the 3-port i much better at holding a steady boost curve. It reacts faster and you can run a faster correction interval to catch spikes. I went with the Perrin solenoid because I got it on clearance for $35. If you can't find one at that price, the GM 3-port is the best option.
However, this is coming from the person who probably relies on the TBEC the most of all of the BCS tuners. I tune my WGDC to specifically rely on the TBEC table for seasonal stability. If you use the more common method of fine tuning the WGDC and capping upward correction via the max correction table, the stock solenoid will likely work as well as a 3-port.
]
However, this is coming from the person who probably relies on the TBEC the most of all of the BCS tuners. I tune my WGDC to specifically rely on the TBEC table for seasonal stability. If you use the more common method of fine tuning the WGDC and capping upward correction via the max correction table, the stock solenoid will likely work as well as a 3-port.
However, this is coming from the person who probably relies on the TBEC the most of all of the BCS tuners. I tune my WGDC to specifically rely on the TBEC table for seasonal stability. If you use the more common method of fine tuning the WGDC and capping upward correction via the max correction table, the stock solenoid will likely work as well as a 3-port.
Yes. Apparently a boost solenoid is a boost solenoid. 2 wires and it just works. I'm honestly slightly baffled by it.
GM Solenoids run about $40 i think shipped with the harness pigtail. There are part numbers in the GM 3-port install and tune thread.
GM Solenoids run about $40 i think shipped with the harness pigtail. There are part numbers in the GM 3-port install and tune thread.
Boost solenoids and MBC's alike should be connected to the correct ports. Try blowing on the different ports and note the results. Follow mfr instructions. The second bold paragraph discusses why you would want to hook up a solenoid properly.
Good stuff on Wiki http://en.wikipedia.org/wiki/Boost_controller
Electronic boost control
A 3-port pneumatic solenoid. This solenoid allows interrupt or blocking of the boost pressure rather than just bleed type control.Electronic boost control adds an air control solenoid and/or a stepper motor controlled by an electronic control unit. The same general principle of a manual controller is present, which is to control the air pressure presented to the wastegate actuator. Further control and intelligent algorithms can be introduced, refining and increasing control over actual boost pressure delivered to the engine.
At the component level, boost pressure can either be bled out of the control lines or blocked outright. Either can achieve the goal of reducing pressure pushing against the wastegate. In a bleed-type system air is allowed to pass out of the control lines, reducing the load on the wastegate actuator. On a blocking configuration, air traveling from the charge air supply to the wastegate actuator is blocked while simultaneously bleeding any pressure that has previously built up at the wastegate actuator.
Control details
A 4-port pneumatic solenoid installed to control a dual port wastegate controlled by a single PWM PID controllerControl for the solenoids and stepper motors can be either closed loop or open loop. Closed loop systems rely on feedback from a manifold pressure sensor to meet a predetermined boost pressure. Open loop systems have a predetermined control output where control output is merely based on other inputs such as throttle angle and/or engine RPM. Open loop specifically leaves out a desired boost level, while closed loop attempts to target a specific level of boost pressure. Since open loop systems do not modify control levels based on MAP sensor, differing boost pressure levels may be reached based on outside variables such as weather conditions or engine coolant temperature. For this reason, systems that do not feature closed loop operation are not as widespread.
Solenoids are driven by pulse-width modulation as they are binary state devices, either allowing air flow or blocking it between any two given ports. By modifying the pulse width at a sufficiently high frequency, average air pressure over time can be controlled. Solenoids may require small diameter restrictors be installed in the air control lines to limit airflow and even out the on/off nature of their operation.
Stepper motors allow fine control of airflow based on position and speed of the motor, but may have low total airflow capability. Some systems use a solenoid in conjunction with a stepper motor, with the stepper motor allowing fine control and the solenoid coarse control.
Many configurations are possible with 2-, 3-, and 4-port solenoids and stepper motors in series or parallel. Two port solenoid bleed systems with a PID controller tend to be common on factory turbocharged cars.
Advantages
Since less positive pressure can be present at the wastegate actuator as desired boost is approached the wastegate remains closer to a completely closed state. This keeps exhaust gas routed through the turbine and increases energy transferred to the wheels of the turbocharger. Once desired boost is reached, closed loop based systems react by allowing more air pressure to reach the wastegate actuator to stop the further increase in air pressure so desired boost levels are maintained. This reduces turbocharger lag and lowers boost threshold. Boost pressure builds faster when the throttle is depressed quickly and allows boost pressure to build at lower engine RPM than without such a system.
This also allows the use of a much softer spring in the actuator. For instance, a 7 psi spring together with a boost controller may still be able to achieve a maximum boost level of well over 15 psi. The electronic control unit can be programmed to control 7 psi at half throttle, 12 psi at 3/4 throttle, and 15 psi at full throttle, or whatever levels the programmer or designer of the control unit intends. This partial throttle control greatly increases driver control over the engine and vehicle.
Limitations and Disadvantages
Even with an electronic controller, actuator springs that are too soft can cause the wastegate to open before desired. Exhaust gas backpressure is still pushing against the wastegate valve itself. This backpressure can overcome the spring pressure without the aid of the actuator at all. Electronic control may still enable control of boost to over double gauge pressure of the spring's rated pressure.
The solenoid and stepper motors also need to be installed in such a way to maximize the advantages of failure modes. For instance, if a solenoid is installed to control boost electronically, it should be installed such that if the solenoid fails in the most common failure mode (probably non-energized position) the boost control falls back to simple wastagate actuator boost levels. It is possible a solenoid or stepper motor could get stuck in a position that lets no boost pressure reach the wastegate, causing boost to quickly rise out of control.
The electronic systems, extra hoses, solenoids and soforth add complexity to the turbocharger system. This runs counter to the "keep it simple" principle as there are more things that can go wrong. It is worth noting that virtually all modern factory turbocharged cars, the same cars with long warranty periods, implement electronic boost control. Manufactures such as Subaru, Mitsubishi and Saab integrate electronic boost control in all turbo model cars.
Good stuff on Wiki http://en.wikipedia.org/wiki/Boost_controller
Electronic boost control
A 3-port pneumatic solenoid. This solenoid allows interrupt or blocking of the boost pressure rather than just bleed type control.Electronic boost control adds an air control solenoid and/or a stepper motor controlled by an electronic control unit. The same general principle of a manual controller is present, which is to control the air pressure presented to the wastegate actuator. Further control and intelligent algorithms can be introduced, refining and increasing control over actual boost pressure delivered to the engine.
At the component level, boost pressure can either be bled out of the control lines or blocked outright. Either can achieve the goal of reducing pressure pushing against the wastegate. In a bleed-type system air is allowed to pass out of the control lines, reducing the load on the wastegate actuator. On a blocking configuration, air traveling from the charge air supply to the wastegate actuator is blocked while simultaneously bleeding any pressure that has previously built up at the wastegate actuator.
Control details
A 4-port pneumatic solenoid installed to control a dual port wastegate controlled by a single PWM PID controllerControl for the solenoids and stepper motors can be either closed loop or open loop. Closed loop systems rely on feedback from a manifold pressure sensor to meet a predetermined boost pressure. Open loop systems have a predetermined control output where control output is merely based on other inputs such as throttle angle and/or engine RPM. Open loop specifically leaves out a desired boost level, while closed loop attempts to target a specific level of boost pressure. Since open loop systems do not modify control levels based on MAP sensor, differing boost pressure levels may be reached based on outside variables such as weather conditions or engine coolant temperature. For this reason, systems that do not feature closed loop operation are not as widespread.
Solenoids are driven by pulse-width modulation as they are binary state devices, either allowing air flow or blocking it between any two given ports. By modifying the pulse width at a sufficiently high frequency, average air pressure over time can be controlled. Solenoids may require small diameter restrictors be installed in the air control lines to limit airflow and even out the on/off nature of their operation.
Stepper motors allow fine control of airflow based on position and speed of the motor, but may have low total airflow capability. Some systems use a solenoid in conjunction with a stepper motor, with the stepper motor allowing fine control and the solenoid coarse control.
Many configurations are possible with 2-, 3-, and 4-port solenoids and stepper motors in series or parallel. Two port solenoid bleed systems with a PID controller tend to be common on factory turbocharged cars.
Advantages
Since less positive pressure can be present at the wastegate actuator as desired boost is approached the wastegate remains closer to a completely closed state. This keeps exhaust gas routed through the turbine and increases energy transferred to the wheels of the turbocharger. Once desired boost is reached, closed loop based systems react by allowing more air pressure to reach the wastegate actuator to stop the further increase in air pressure so desired boost levels are maintained. This reduces turbocharger lag and lowers boost threshold. Boost pressure builds faster when the throttle is depressed quickly and allows boost pressure to build at lower engine RPM than without such a system.
This also allows the use of a much softer spring in the actuator. For instance, a 7 psi spring together with a boost controller may still be able to achieve a maximum boost level of well over 15 psi. The electronic control unit can be programmed to control 7 psi at half throttle, 12 psi at 3/4 throttle, and 15 psi at full throttle, or whatever levels the programmer or designer of the control unit intends. This partial throttle control greatly increases driver control over the engine and vehicle.
Limitations and Disadvantages
Even with an electronic controller, actuator springs that are too soft can cause the wastegate to open before desired. Exhaust gas backpressure is still pushing against the wastegate valve itself. This backpressure can overcome the spring pressure without the aid of the actuator at all. Electronic control may still enable control of boost to over double gauge pressure of the spring's rated pressure.
The solenoid and stepper motors also need to be installed in such a way to maximize the advantages of failure modes. For instance, if a solenoid is installed to control boost electronically, it should be installed such that if the solenoid fails in the most common failure mode (probably non-energized position) the boost control falls back to simple wastagate actuator boost levels. It is possible a solenoid or stepper motor could get stuck in a position that lets no boost pressure reach the wastegate, causing boost to quickly rise out of control.
The electronic systems, extra hoses, solenoids and soforth add complexity to the turbocharger system. This runs counter to the "keep it simple" principle as there are more things that can go wrong. It is worth noting that virtually all modern factory turbocharged cars, the same cars with long warranty periods, implement electronic boost control. Manufactures such as Subaru, Mitsubishi and Saab integrate electronic boost control in all turbo model cars.
Last edited by Mr. Evo IX; Jun 9, 2008 at 01:59 PM.
With the GM, the metal port is connected to a boost source (compressor outlet, etc), the top port on the 2 port side is connected to the wastegate actuator and the bottom port (that comes with the little foam filter on it) is connected to the nipple on the underside of the induction tube.