ECU controlling boost???

[Negreac]

Does anyone know whether the ECU is capable fo controling boost levels? If not than what is the purpose of the wastegate valve control solenoid? Any info is appreciated.

[Negreac]

Well, I'm fairly certain the ECU is not capable of controling boost levels on our cars? But that still begs the question as to what the purpose of the wastegate valve control solenoid is? Come on, someone has to know or at least have some theories.

[DMC]

im pretty sure its for electroic boost controllers

[Negreac]

Huh? The wastegate valve control solenoid is a stock solenoid which controls a vaccumm/boost line that runs from the piping (before the compressor but after the MAFS) to a T in the waste gate actuator vaccum line. So in theory by opening the solenoid the boost pressure could be released back into the ambient intake instead of being used to open the wastegate, resulting in higher boost. However, people are saying that the ECU doesn't control boost, in which case I can't think of any other purpose for the solenoid. It's mounted right below the ignitor chip for those people who don't know what part I'm talking about. From my understanding it's unecessary and the majority of SR 240's aren't using it. However, my clip came with a tuned ECU, and if it is possible to control boost with the ECU then this ECU may very well be set up for a minor increase in boost, in which case I'd need the solenoid. See my dillema? Any help is appreciated.

[Steeles]

Originally posted by Negreac
Huh? The wastegate valve control solenoid is a stock solenoid which controls a vaccumm/boost line that runs from the piping (before the compressor but after the MAFS) to a T in the waste gate actuator vaccum line. So in theory by opening the solenoid the boost pressure could be released back into the ambient intake instead of being used to open the wastegate, resulting in higher boost. However, people are saying that the ECU doesn't control boost, in which case I can't think of any other purpose for the solenoid. It's mounted right below the ignitor chip for those people who don't know what part I'm talking about. From my understanding it's unecessary and the majority of SR 240's aren't using it. However, my clip came with a tuned ECU, and if it is possible to control boost with the ECU then this ECU may very well be set up for a minor increase in boost, in which case I'd need the solenoid. See my dillema? Any help is appreciated.

I was told when asked what it was when doing my swap was it was there as a limiter. Not letting you run more than 7psi. iirc it has no electrical connection on it. just vacumn lines therefore it has no way of talking to the ecu anyway. (i could be wrong but off the top of my head I dont rememeber any plugs on it....

[Negreac]

It does have a plug, it's a solenoid.

[720_datsun]

Originally posted by Steeles
I was told when asked what it was when doing my swap was it was there as a limiter. Not letting you run more than 7psi. iirc it has no electrical connection on it. just vacumn lines therefore it has no way of talking to the ecu anyway. (i could be wrong but off the top of my head I dont rememeber any plugs on it.... ok i can answer this one yay. your ecu wont beable to provide correct fuel for higher boost levels. from what ive heard and read. but i could be wrong. if you dont want to get a whole new ecu you could always get a piggy back one.

[Negreac]

uhhhh.... that had nothing to do with the topic....

[720_datsun]

Originally posted by Negreac
uhhhh.... that had nothing to do with the topic.... how does it not? you asked if the ecu could control boost and im telling you what the ecu does and why it wont boost over 7 psi, or atleast what i think. so stfu and this thread should be in tech talk not here.

[old_s13]

Originally posted by 720_datsun
how does it not? you asked if the ecu could control boost and im telling you what the ecu does and why it wont boost over 7 psi, or atleast what i think. so stfu and this thread should be in tech talk not here.

:)

he TOLD you! haha

[rednerd]

You are talking about an S14 Sr20det engine, right?

[Negreac]

Originally posted by 720_datsun
how does it not? you asked if the ecu could control boost and im telling you what the ecu does and why it wont boost over 7 psi, or atleast what i think. so stfu and this thread should be in tech talk not here.

The question was whether or not the ECU is capable of controlling boost. You told me that "the ecu wont beable to provide correct fuel for higher boost levels. from what ive heard and read. but i could be wrong. if you dont want to get a whole new ecu you could always get a piggy back one." The fuel capabilities of the stock ECU has almost nothing to do with wastegate/boost control, thus why your response was way off base. BTW the stock ECU is capable of running up to about 15 psi, so not omly were you off topic, you were wrong. However, I do agree with you that this thread belongs in tech talk. I thought I was in tech talk when I originally created it, but later realized I was in chat.


Originally posted by old_s13
he TOLD you! haha

Riiiight...:loco:

Originally posted by rednerd
You are talking about an S14 Sr20det engine, right?

The particular engine I'm dealing with is a S13 SR20DET but I believe all the SR20DETs have a wastegate valve control solenoid, so this thread could potentially apply to the S14 SR, I'd have to go look at the FSM to confirm this.

[DoriftoSlut]

ECU should not have ANYTHING to do with boost. ECU gets volt readings from the mafs, cas, iav and tps and then injects the correct amount of fuel it determines to be necesary for your car. Boost capabilites should be limited by your injectors, of which the ecu would then have to be tuned to compensate for.

Basicaaly you could be running 1 bar, 2 bar, .5 bar, 89 bar whatever... your ecu will only recieve the volt readings from the mafs, it is unconcerned with your turbo and wastegate. All that good stuff is run from pressure and vaccuum changes.

So if you wnat to know if you have a tuned ECU you should check what size injectors you have first.

[DuffMan]

I think the purpose of that solenoid is to keep the wastegate from seeing boost until the turbo has actually reached 7psi, resulting in slightly faster spool up. Could you tune an ECU to restrict that solenoid to create higher boost? I dunno. I've never seen anything about anyone doing that though.

[720_datsun]

Originally posted by Negreac
The question was whether or not the ECU is capable of controlling boost. You told me that "the ecu wont beable to provide correct fuel for higher boost levels. from what ive heard and read. but i could be wrong. if you dont want to get a whole new ecu you could always get a piggy back one." The fuel capabilities of the stock ECU has almost nothing to do with wastegate/boost control, thus why your response was way off base. BTW the stock ECU is capable of running up to about 15 psi, so not omly were you off topic, you were wrong. However, I do agree with you that this thread belongs in tech talk. I thought I was in tech talk when I originally created it, but later realized I was in chat.




Riiiight...:loco:



The particular engine I'm dealing with is a S13 SR20DET but I believe all the SR20DETs have a wastegate valve control solenoid, so this thread could potentially apply to the S14 SR, I'd have to go look at the FSM to confirm this. wow did you just tottaly look stupid. the title of your thread is ecu controlling boost. in the first sentence on your response you say "The question was whether or not the ECU is capable of controlling boost". k you must not be reading stuff huh.

[Negreac]

Originally posted by 720_datsun
wow did you just tottaly look stupid. the title of your thread is ecu controlling boost. in the first sentence on your response you say "The question was whether or not the ECU is capable of controlling boost". k you must not be reading stuff huh.

I don't see the problem in my response...

Originally posted by DuffMan
I think the purpose of that solenoid is to keep the wastegate from seeing boost until the turbo has actually reached 7psi, resulting in slightly faster spool up. Could you tune an ECU to restrict that solenoid to create higher boost? I dunno. I've never seen anything about anyone doing that though.

Thanks, that sounds like a feasible purpose. That goes along well with the lag and drop off rumors that I heard.

[mrmephistopheles]

okay
question's been answered.

moving to tech talk for this thread to gather dust.