GT2871 USERS. SR motor

[bshotts]

Yay someone else who went through controls nonsense! Actually, it's funny how you explained the PID control used in most control logic feedback loops....because you'd think you'd never really get the chance to use that kind of knowledge sitting through the class and exams but alas, here we are talking about electronic boost control, of which most people couldn't care less about how it works, but without all the complicated, behind-the-scenes logic using calculus, there would be no fine tuning of boost.

Good explanation Jspaeth....where'd you finish your undergrad? I guess we could also argue that using a block diagram and modeling the ICE and turbocharger and with some assumptions, calculate the precise numbers to manipulate how the boost controller performs. I'll task you with that portion since you chimed in on PID control haha.

[jspaeth]

Originally Posted by bshotts

Yay someone else who went through controls nonsense! Actually, it's funny how you explained the PID control used in most control logic feedback loops....because you'd think you'd never really get the chance to use that kind of knowledge sitting through the class and exams but alas, here we are talking about electronic boost control, of which most people couldn't care less about how it works, but without all the complicated, behind-the-scenes logic using calculus, there would be no fine tuning of boost.

Good explanation Jspaeth....where'd you finish your undergrad? I guess we could also argue that using a block diagram and modeling the ICE and turbocharger and with some assumptions, calculate the precise numbers to manipulate how the boost controller performs. I'll task you with that portion since you chimed in on PID control haha.

Haha went to U of Delaware for my BS in Chem Eng, right now doing my PhD at Princeton.

I would like to design and sell an off-the shelf (like Greddy Profec of Apexi AVC-R) boost controller that has gear-specific duty versus RPM curves.

Right now, the AVC-R says it does gear specific, but it's not really....you can just decrease the WHOLE duty in a given gear but not each RPM point.

I'd like a EBC where you can dial in duty vs. RPM for each gear separately.

This way you could have a 600 whp car RWD with perfectly good traction in 1st and 2nd gear.

I don't know why no company offers this yet, I could sure use it on my car.

[2fast4y0u]

Originally Posted by slider2828

Hence using the later gen Profec E-01 is soooo much better... can be based on RPM and speed....

Originally Posted by jspaeth
Hmmmm well gain is a "controls" term....I remember this vaguely from my Controls class in undergrad.

Most feedback controllers are PID controllers.....Proportional (to the difference between current point and target), Integral (involving an integral over past history of this difference), and Derivative (involving instantaneous time derivatives of this difference).

Different amounts of the P,I, and D (each has their own "gain") determines the behavior.

Ideally, we want a "critically damped" boost controller.....this is the case in which the boost climbs towards the target as quickly as it possibly can, and then when it gets there, it stays there (no oscillations or overshoot).

Underdamped would cause overshoot and oscillations, overdamped would cause it not to approach as fast as it possibly could.

I like the APEX'i because it truly allows you to do this, jack up the duty in the lower RPM to help it reach full boost faster, and then tinker with the duties in the higher RPM to KEEP it there.

MBC is just crude in comparison

Originally Posted by jspaeth

Haha went to U of Delaware for my BS in Chem Eng, right now doing my PhD at Princeton.

I would like to design and sell an off-the shelf (like Greddy Profec of Apexi AVC-R) boost controller that has gear-specific duty versus RPM curves.

Right now, the AVC-R says it does gear specific, but it's not really....you can just decrease the WHOLE duty in a given gear but not each RPM point.

I'd like a EBC where you can dial in duty vs. RPM for each gear separately.

This way you could have a 600 whp car RWD with perfectly good traction in 1st and 2nd gear.

I don't know why no company offers this yet, I could sure use it on my car.

my head just

[slider2828]

Originally Posted by jspaeth

Haha went to U of Delaware for my BS in Chem Eng, right now doing my PhD at Princeton.

I would like to design and sell an off-the shelf (like Greddy Profec of Apexi AVC-R) boost controller that has gear-specific duty versus RPM curves.

Right now, the AVC-R says it does gear specific, but it's not really....you can just decrease the WHOLE duty in a given gear but not each RPM point.

I'd like a EBC where you can dial in duty vs. RPM for each gear separately.

This way you could have a 600 whp car RWD with perfectly good traction in 1st and 2nd gear.

I don't know why no company offers this yet, I could sure use it on my car.

Can't Motec and Autec's do this and also maybe AEM?

[jspaeth]

Originally Posted by slider2828

Can't Motec and Autec's do this and also maybe AEM?

Yes! Notice I said off-the-shelf......basically I meant something other than a full standalone ECU....like something that works on its own, like a Profec or AVC-R.

You shouldn't have to spend $1500++ to get this technology. The AVC-R for example already knows which gear you are in....

Adding in separate tables of duty VS RPM should be rather trivial to implement, but VERY helpful for those of us with traction issues in the lower gears

[Max_PSi]

Originally Posted by jspaeth

Yes! Notice I said off-the-shelf......basically I meant something other than a full standalone ECU....like something that works on its own, like a Profec or AVC-R.

You shouldn't have to spend $1500++ to get this technology. The AVC-R for example already knows which gear you are in....

Adding in separate tables of duty VS RPM should be rather trivial to implement, but VERY helpful for those of us with traction issues in the lower gears

I just about done with my 2871r install. I have all the supporting mods including the PFC with the optional boost controller kit. Would this controller be simliar to the stand-alones previously mentioned?

And if so why not get this kit jspaeth instead of run the AVC-R? I think brand new they both run for about the same price. And you have the PFC right?

[S13 curtis]

Originally Posted by slider2828

Can't Motec and Autec's do this and also maybe AEM?

YESIR, the aem ems can control boost in each gear if you have the boost solenoid for it. Its bad ass.

My car should be ready to hit the dyno(Mustang Dyno @ Central Florida Turbo aka CFT) in mid to late january just waiting on the rest of the parts to come in, then it will be posted.