Electronic Feedback (active) Boost Controller -- have a cheap prototype need input
- Thread starter Darth Fiero
- Start date
Originally posted by Razor
OOOPPPPS.. Your absolutely rite. The sheet I saw wasnt for an absolute sensor.. unless reading data sheets at night did that too me.
Funny how one of the casings has a vacuum port. But thats not needed.
Probably reading too much DIY-EFI
Those late night datasheet readings will kill you, trust me I know. I had the orientation of a couple ICs on my digital final wrong, ended up having to redo a quarter of a breadboard. Next semester I'm getting to play with 8031s, I'm really eager to do that, it'll give me a step towards being able to code for Motorola and therefore GM boxes. I'm slightly proficient in PIC micros, as in I can understand what's going on and probalby write a program up if given enough time.
salvageV6
Daily Driver
- Joined
- May 25, 2001
The GM sensor from GM Parts is $53+ now, plus $11 shipping so the total is about $65 to your door from them.
Newark Electronics has much cheaper shipping but since that "issue" was brought up I thought it needed clarification.
In the future, when is unspecified by GM Parts, the connector on the GM 3 bar will change necessitating cutting the factory harness or else buying or making a plug and play adatper. Mo' $$$ money.
You can get your own 5 volt reference from IGN power real easy for DIY projects and keep it inside the electronics package where it belongs. No need to tap off the ECM's +5 power at all.
1 ampere voltage regulator 7805 a 3 wire device available easily at Radio Shack 276-1770 which has the highest price on the planet I'm sure for the device at $1.69.
Remember both the MPX pressure tranducer and the voltage regulator are 3 wire devices easy to work with even for a novice.
Should you need to run higher amperage relays or something off the 5 volt 3 wire regulator you may need a heat sink, also available at R.S., but is not needed when running the Motorola MAP sensor and LED's and a several logic chips.
I used the 5 volt regulator to run the chips and LED's and a transistor that switches IGN voltage of +12 to run a true automotive type relay to run my alky. pump hot wired.
Easy to interface the 5 volt stuff with 12 volt things when it's all in one box and on one board. I don't like using the +12 ECM power or the +5 voltage from it for other projects myself, I prefer to run a wire off IGN power for accessories such as the BSTC that wire over near the ECM. Others have successfully wired to the EMC power for years so it's simply a matter of preference for the wiring and fusing of aftermarket equipment or DIY equipment.
The Motorola lit. available has all five sensors and packages in one 4250 family on one .pdf set of data sheets, gauge, differential, absolute, etc.
Find the one you need to use for your application they are out there.......
Newark Electronics has much cheaper shipping but since that "issue" was brought up I thought it needed clarification.
In the future, when is unspecified by GM Parts, the connector on the GM 3 bar will change necessitating cutting the factory harness or else buying or making a plug and play adatper. Mo' $$$ money.
You can get your own 5 volt reference from IGN power real easy for DIY projects and keep it inside the electronics package where it belongs. No need to tap off the ECM's +5 power at all.
1 ampere voltage regulator 7805 a 3 wire device available easily at Radio Shack 276-1770 which has the highest price on the planet I'm sure for the device at $1.69.
Remember both the MPX pressure tranducer and the voltage regulator are 3 wire devices easy to work with even for a novice.
Should you need to run higher amperage relays or something off the 5 volt 3 wire regulator you may need a heat sink, also available at R.S., but is not needed when running the Motorola MAP sensor and LED's and a several logic chips.
I used the 5 volt regulator to run the chips and LED's and a transistor that switches IGN voltage of +12 to run a true automotive type relay to run my alky. pump hot wired.
Easy to interface the 5 volt stuff with 12 volt things when it's all in one box and on one board. I don't like using the +12 ECM power or the +5 voltage from it for other projects myself, I prefer to run a wire off IGN power for accessories such as the BSTC that wire over near the ECM. Others have successfully wired to the EMC power for years so it's simply a matter of preference for the wiring and fusing of aftermarket equipment or DIY equipment.
The Motorola lit. available has all five sensors and packages in one 4250 family on one .pdf set of data sheets, gauge, differential, absolute, etc.
Find the one you need to use for your application they are out there.......
Originally posted by salvageV6
The GM sensor from GM Parts is $53+ now, plus $11 shipping so the total is about $65 to your door from them.
Newark Electronics has much cheaper shipping but since that "issue" was brought up I thought it needed clarification.
In the future, when is unspecified by GM Parts, the connector on the GM 3 bar will change necessitating cutting the factory harness or else buying or making a plug and play adatper. Mo' $$$ money.
You can get your own 5 volt reference from IGN power real easy for DIY projects and keep it inside the electronics package where it belongs. No need to tap off the ECM's +5 power at all.
1 ampere voltage regulator 7805 a 3 wire device available easily at Radio Shack 276-1770 which has the highest price on the planet I'm sure for the device at $1.69.
Remember both the MPX pressure tranducer and the voltage regulator are 3 wire devices easy to work with even for a novice.
Should you need to run higher amperage relays or something off the 5 volt 3 wire regulator you may need a heat sink, also available at R.S., but is not needed when running the Motorola MAP sensor and LED's and a several logic chips.
I used the 5 volt regulator to run the chips and LED's and a transistor that switches IGN voltage of +12 to run a true automotive type relay to run my alky. pump hot wired.
Easy to interface the 5 volt stuff with 12 volt things when it's all in one box and on one board. I don't like using the +12 ECM power or the +5 voltage from it for other projects myself, I prefer to run a wire off IGN power for accessories such as the BSTC that wire over near the ECM. Others have successfully wired to the EMC power for years so it's simply a matter of preference for the wiring and fusing of aftermarket equipment or DIY equipment.
The Motorola lit. available has all five sensors and packages in one 4250 family on one .pdf set of data sheets, gauge, differential, absolute, etc.
Find the one you need to use for your application they are out there.......
By any chance you wouldn't happen to have any data on the 2 bar GM map would you? I'm gonna start playing around with it as soon as I can get the ADC on this PIC working well, These data sheets are about a quarter mile long
I'm not a fan of tabbed browing for the most part, but opening up 2 or 3 of the datasheet in different tabs to stay on different sections seems to be working great. the big thing I'm doing is just trying to figure out what I need to set the control bits to, these things are really particular about what they want. I've got a PICKIT1 development board I'm playing with, the way to go for learning these IMHO.
salvageV6
Daily Driver
- Joined
- May 25, 2001
I don't have any information on the GM 2 bar, sorry.
The boost gauge still works on my car and is only off 4 psi. or so, not bad for 18 years, I am guessing it's the dash logic and voltage comparators more than the MAP itself but not worth investigating at this point.
Actually for what I'm doing good old 70's and 80's logic chips are working just fine and are cheap and plentiful from collecting junk over the years.
LM3914's, fancy but cheap voltage comparators, will be used for the boost gauge and can also be used for an A/F meter DIY project.
Since they source current for the LEDs and will work better than open collectors for me I can use NPN instead of PNP transistors to drive relays to control "stuff". Up to 36psi. with this version.
Boost controllers will need a very good PID loop to work I believe.
What exactly are you looking to do with the PIC controller and the MAP?
The boost gauge still works on my car and is only off 4 psi. or so, not bad for 18 years, I am guessing it's the dash logic and voltage comparators more than the MAP itself but not worth investigating at this point.
Actually for what I'm doing good old 70's and 80's logic chips are working just fine and are cheap and plentiful from collecting junk over the years.
LM3914's, fancy but cheap voltage comparators, will be used for the boost gauge and can also be used for an A/F meter DIY project.
Since they source current for the LEDs and will work better than open collectors for me I can use NPN instead of PNP transistors to drive relays to control "stuff". Up to 36psi. with this version.
Boost controllers will need a very good PID loop to work I believe.
What exactly are you looking to do with the PIC controller and the MAP?
More then anything right now I'm wanting to get my feet wet. Eventually I'm wanting to do is build a boost controller that also controls fuel and possibly LPG dump injection, probably liquid propane via nitrous "pills" to control the flow. The only problem being that the pressure of the LPG will vary drasticly, which means I've gotta figure out a way to regulate the liquid pressure OR make it constant (bottle warmer)
Darth Fiero
3800 Series II Turbo
- Joined
- Jan 12, 2003
The weather broke and I had some spare time between projects so I finally got around to installing this boost controller.
Well I can tell you right off the bat it works great. The controller can change output state faster than the wastegate solenoid can actuate. Only issue I am running into right now is I am trying to use a stock GN wastegate actuator that has been modified to be adjustible but the minimum boost I can adjust it for is 10psi, even with the wastegate solenoid commanding minimum boost.
Anyway, if I hold the gas at part throttle to maintain about 5psi of boost I can adjust the knob on the boost controller and the boost will follow the knob super accurately without hesitation or spiking. What I need to do at this point is get this thing hooked up to my buddy's Turbo-T and try it out on that to see how well it works.
I have been listening to some suggestions and have passed some along to the builder of this boost controller. Here are the suggestions I have made:
-Keep current design with switchable 2/3 Bar Sensor input
-Add 3rd gear input to make boost drop when sensed...make the amount of boost drop adjustable
-Add ramp-up boost limiting function -- adjustable rate
-Change output solenoid control from ON/OFF to PWM D/C% like factory GN. (does anyone know the frequency (hz) these operate at?)
Basically what you are going to end up with is a boost controller that has one large knob for master boost limit adjust, and two smaller adjusters (req small screwdriver) that control 3rd gear limit and boost ramp-up rate.
What do you think?
Well I can tell you right off the bat it works great. The controller can change output state faster than the wastegate solenoid can actuate. Only issue I am running into right now is I am trying to use a stock GN wastegate actuator that has been modified to be adjustible but the minimum boost I can adjust it for is 10psi, even with the wastegate solenoid commanding minimum boost.
Anyway, if I hold the gas at part throttle to maintain about 5psi of boost I can adjust the knob on the boost controller and the boost will follow the knob super accurately without hesitation or spiking. What I need to do at this point is get this thing hooked up to my buddy's Turbo-T and try it out on that to see how well it works.
I have been listening to some suggestions and have passed some along to the builder of this boost controller. Here are the suggestions I have made:
-Keep current design with switchable 2/3 Bar Sensor input
-Add 3rd gear input to make boost drop when sensed...make the amount of boost drop adjustable
-Add ramp-up boost limiting function -- adjustable rate
-Change output solenoid control from ON/OFF to PWM D/C% like factory GN. (does anyone know the frequency (hz) these operate at?)
Basically what you are going to end up with is a boost controller that has one large knob for master boost limit adjust, and two smaller adjusters (req small screwdriver) that control 3rd gear limit and boost ramp-up rate.
What do you think?
Darth Fiero
3800 Series II Turbo
- Joined
- Jan 12, 2003
Not yet, I would like to test it out on my friend's GN before we start selling them just to make sure they work as desired. Unfortuneately, winter is not ready to give up and move on and the GN's are still safely in storage. I will advise when we make progress on the testing.
Darth Fiero
3800 Series II Turbo
- Joined
- Jan 12, 2003
Boost Controller TESTED on a GN
I finally tested the "simple" boost controller on a friend's 87 Turbo T. At part throttle, it was so accurate in its control you could set you watch by it. However, at WOT, there are other issues that are not electrically-related.
My friend's T has a TE-61 turbo amoung other things like Ford FMIC, built engine, etc. We "think" he is still using a factory (modified-adjustable) wastegate actuator. The current wastegate actuator is UNABLE to keep the boost level below 20psi. Before I installed the boost-controller, he was having issues with boost-creep. With the controller installed, the boost would immediately climb to the set point, then would slowly creep up to 20psi at higher-RPM's. I unplugged the vac line from the boost solenoid and plugged it, which should result in only allowing minimum boost to build. With the vac line plugged (allowing full pressure to reach the wastegate actuator), the boost would come up to 10psi, but then slowly creep up as the RPM's climb, eventually to 20psi. Since neither the boost controller or wastegate were in the loop during this test, I have to assume the existing wastegate ACTUATOR is to blame.
He bought his turbo from PTE, so I advised him to give them a call and see if they recommend a different actuator.
I finally tested the "simple" boost controller on a friend's 87 Turbo T. At part throttle, it was so accurate in its control you could set you watch by it. However, at WOT, there are other issues that are not electrically-related.
My friend's T has a TE-61 turbo amoung other things like Ford FMIC, built engine, etc. We "think" he is still using a factory (modified-adjustable) wastegate actuator. The current wastegate actuator is UNABLE to keep the boost level below 20psi. Before I installed the boost-controller, he was having issues with boost-creep. With the controller installed, the boost would immediately climb to the set point, then would slowly creep up to 20psi at higher-RPM's. I unplugged the vac line from the boost solenoid and plugged it, which should result in only allowing minimum boost to build. With the vac line plugged (allowing full pressure to reach the wastegate actuator), the boost would come up to 10psi, but then slowly creep up as the RPM's climb, eventually to 20psi. Since neither the boost controller or wastegate were in the loop during this test, I have to assume the existing wastegate ACTUATOR is to blame.
He bought his turbo from PTE, so I advised him to give them a call and see if they recommend a different actuator.
Apply 20 psi air pressure to the actuator, and check for air leaks or movement. If you can apply the air, then shut it off, you should be able to detect any leaks.
The wastgate hole in the turbo might not be capable of bypassing enough exh gas around the turbine to lower the boost pressure. Try this: disconnect the rod from the actuator. The puck should easily blow open. you shouldn't be getting any boost whatsoever.
The wastgate hole in the turbo might not be capable of bypassing enough exh gas around the turbine to lower the boost pressure. Try this: disconnect the rod from the actuator. The puck should easily blow open. you shouldn't be getting any boost whatsoever.
Darth Fiero
3800 Series II Turbo
- Joined
- Jan 12, 2003
UPDATE: Schematics for this controller have been released!
I have been authorized to release the schematics for the simple boost controller a guy made for me some time ago. Originally, this guy was going to redesign the boost controller based on feedback from this thread, here on TB.com. Events and family commitments have prevented further work on this design so this guy has authorized the public release of the design schematics in the hopes people can put it to good use.
This is an adjustable electronic boost controller. It can be built to work with either a 2-bar or 3-bar external MAP sensor. It is designed to control the ground side of a wastegate solenoid. It has the following inputs and outputs:
Input:
-12v + battery
-Ground
-MAP sensor signal
Output:
-5volt reference for MAP sensor
-Ground for MAP sensor
-Wastegate Solenoid (controls ground side of solenoid like factory)
I have been using this controller on my car for over 2 years now and it works great! It is a simple on/off control unit, so there is no way to adjust boost ramp-up rates or wastegate solenoid duty cycles. In my application, it controls boost accurately and flawlessly. The designer and builder of this boost controller has given permission for 3rd parties to alter his design in order to upgrade it. Please read the authorization text file enclosed with the schematics and pictures for more information.
http://dtcc.cz28.com/files/simple_boost_controller.zip
-ryan
I have been authorized to release the schematics for the simple boost controller a guy made for me some time ago. Originally, this guy was going to redesign the boost controller based on feedback from this thread, here on TB.com. Events and family commitments have prevented further work on this design so this guy has authorized the public release of the design schematics in the hopes people can put it to good use.
This is an adjustable electronic boost controller. It can be built to work with either a 2-bar or 3-bar external MAP sensor. It is designed to control the ground side of a wastegate solenoid. It has the following inputs and outputs:
Input:
-12v + battery
-Ground
-MAP sensor signal
Output:
-5volt reference for MAP sensor
-Ground for MAP sensor
-Wastegate Solenoid (controls ground side of solenoid like factory)
I have been using this controller on my car for over 2 years now and it works great! It is a simple on/off control unit, so there is no way to adjust boost ramp-up rates or wastegate solenoid duty cycles. In my application, it controls boost accurately and flawlessly. The designer and builder of this boost controller has given permission for 3rd parties to alter his design in order to upgrade it. Please read the authorization text file enclosed with the schematics and pictures for more information.
http://dtcc.cz28.com/files/simple_boost_controller.zip
-ryan
The reason you cant get it below 10 psi, is because that's what the internal spring is rated at (since it's a stock actuator). You can only control boost "down" to the level of the internal spring on wastegates.
Turbo6Smackdown
Well-Known Member
- Joined
- Dec 31, 2005
wow, there's some smart mother******s on here.. I'm glad theyre on our side.
$100 sounds like a good price. But what I would like to see...2 stage boost control. Bracket racing would be sooo much easier if a low staging boost peak could be set and then switched to a higher, separately adjustable setting. Perhaps switched by a the TPS signal or have the low setting activated by the brake switch...brakes on=low staging boost, brakes off higher WOT boost.
I just bought a Turbosmart 2 stage manual controller, it won't adjust low enough or high enough (or I need more time to tune it). There is an electronic 2 stage on the market now,but the 2nd stage has to be manually activated with a switch on the box, inconvenient. 1 neat feature it does have, 2 12V switched outputs which can be used to activate boost sensitive bolts ons. This is neat but all the alky kits I've seen are self contained. Those outputs would be more usefull to do-it-yourselfers. It would be nice to get rid of the contact switch on my thottle linkage I'm using to trigger an intercooler sprayer!
I just bought a Turbosmart 2 stage manual controller, it won't adjust low enough or high enough (or I need more time to tune it). There is an electronic 2 stage on the market now,but the 2nd stage has to be manually activated with a switch on the box, inconvenient. 1 neat feature it does have, 2 12V switched outputs which can be used to activate boost sensitive bolts ons. This is neat but all the alky kits I've seen are self contained. Those outputs would be more usefull to do-it-yourselfers. It would be nice to get rid of the contact switch on my thottle linkage I'm using to trigger an intercooler sprayer!
Darth Fiero
3800 Series II Turbo
- Joined
- Jan 12, 2003
Well when this guy was originally going to make these for resale, he wanted to "upgrade" this design with stuff like 2 stage boost control in mind as well as inputs for trans gear and boost ramp-up rate adjustments; stuff like this. Unfortunately, he has run out of time due to family and job obligations so he can no longer devote any time to the design I posted just a few messages ago.
So what anyone can do is download the aformentioned schematic and either build it as-is for themselves, or tweak/build-on to that design to add the features you want. As it stands now, this boost controller can be built for LESS THAN $20 in parts + the cost of the MAP sensor.
-ryan
What everybody seems to forget is, that to get truely low launch boost. You can't do it on internal (stock type) wastegate actuators because the spring is just too high. Your MINIMUM boost is only going to be as low as what the spring in the wastegate actuator is rated at.
ex. 10# spring = minimum boost of 10#
To get the lower boost levels for launching is going to require an external gate that has a much lower spring pressure. They also have enough dynamic range that even though they can do the lower levels they can also go virtually as high as you need them to. (features not obtainable with a stock type internal swing valve and gate assembly).
Also remember the boost swing available on the stock style actuator being controlled by one solenoid is only going to be about 7-9# (min to max). Adding a second solenoid (to bleed more air away from the actuator) will allow almost (but not quite) double that range.
Here's an example of how I handle all this menutia:
I have a high boost actuator (with a 14# spring).
So.... My minimum boost (no matter what) is 14#, and if I turn my boost controller all the way up to max, I can squeeze out about 21# of boost.
HOWEVER, I also have a second solenoid mounted next to the original, and when at the track, I just plug it in (paralleled connector) and I can now add about another 7-9# of max boost available for racing.
Here's a picture of how the solenoids are mounted/plumbed.
dualsol pictures from cars photos on webshots
