More sophisticated boost blending?
Moderators: jsmcortina, muythaibxr
More sophisticated boost blending?
Okay I know this will probably sound like a joke but please hear me out!
Right now I've got my car set up with CL boost control, with target-table blending based on gear. Boost target table 1 has lower values than table 2, and the blending is set up such that in first gear it uses 100% table 1, in second it's 30% table 1 / 70% table 2, and gears 3-5 it's 100% table 2.
And it works just fine... except when it's really slippery out, like when it's snowing.
What I'd ideally be able to do is, based on an input, switch all of the boost-related tables. So with the input off, it would use boost 1, boost 2, and blend curve 6, and with the input on it would use two other boost target tables and a separate blend curve.
I feel like I've seen requests of this nature here before but don't recall this exact thing... if it's been asked before I apologize.
Does anyone else feel this would be useful?
If not it certainly would not make sense for James & Ken to waste their time on it, and I may just mod the code myself to do it. But if it would benefit others, maybe it's worth the effort?
Right now I've got my car set up with CL boost control, with target-table blending based on gear. Boost target table 1 has lower values than table 2, and the blending is set up such that in first gear it uses 100% table 1, in second it's 30% table 1 / 70% table 2, and gears 3-5 it's 100% table 2.
And it works just fine... except when it's really slippery out, like when it's snowing.
What I'd ideally be able to do is, based on an input, switch all of the boost-related tables. So with the input off, it would use boost 1, boost 2, and blend curve 6, and with the input on it would use two other boost target tables and a separate blend curve.
I feel like I've seen requests of this nature here before but don't recall this exact thing... if it's been asked before I apologize.
Does anyone else feel this would be useful?
If not it certainly would not make sense for James & Ken to waste their time on it, and I may just mod the code myself to do it. But if it would benefit others, maybe it's worth the effort?
Eric Law
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking
Be alert! America needs more lerts.
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking
Be alert! America needs more lerts.
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- Super MS/Extra'er
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Re: More sophisticated boost blending?
Who is this guy?......
I would consider doing something similar with a Honda Vtec motor with the cam timing. Say low cam in 1st, in second big cam over 80% throttle and in taller gears big cam over 4000 RPM.
Just thinking
Andy
I would consider doing something similar with a Honda Vtec motor with the cam timing. Say low cam in 1st, in second big cam over 80% throttle and in taller gears big cam over 4000 RPM.
Just thinking
Andy
Re: More sophisticated boost blending?
Well actually for me the ultimate approach would be, rather than switching, to blend between boost1/boost2/blend6 and boost3/boost4/blendX using another blend table based on an analog input. Yes, I mean blending blending tables based on a blending table.
The analog input could be a "boost" knob on the dash, or in my case, a value sent over CAN from a display thing I'm building. It would be convoluted as he** from a software standpoint, but would be great for the driver who could easily modify the boost characteristics based on available traction.
The analog input could be a "boost" knob on the dash, or in my case, a value sent over CAN from a display thing I'm building. It would be convoluted as he** from a software standpoint, but would be great for the driver who could easily modify the boost characteristics based on available traction.
Eric Law
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking
Be alert! America needs more lerts.
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking
Be alert! America needs more lerts.
Re: More sophisticated boost blending?
Adjusting boost by potentiometer its a good idea. I see this function in some ECUs very comfortable. Personally I want to control CL setup with 2 profiles for boost by gears target limitng and simple switch input to change them.
BMW 525i, stroker 2.8L, MS3-Pro 1.4.1, BIPs 373, 66mm turbo 30 psi
Re: More sophisticated boost blending?
So... what is your right foot doing exactly?
Why cant boost vs tps take care of all of this for you? It's simple and works brilliantly.
Why cant boost vs tps take care of all of this for you? It's simple and works brilliantly.
Toyota Celica GT4/Alltrac with 5S-GTE stroker (2.2L I4 turbo, high CR) on E85 w/FlexFuel.
MS3 + MS3X + KnockBoard + RTC + BT + DIY CAN-IO-Board + DIY CAN Digital Dash.
MS3 + MS3X + KnockBoard + RTC + BT + DIY CAN-IO-Board + DIY CAN Digital Dash.
Re: More sophisticated boost blending?
Well... I'm using boost vs. TPS now and it's okay most of the time. And probably for someone unlike me who has some functioning brain cells and a reaction time faster than half an hour, it would be okay all of the time.
But for me, when I'm driving in a snowstorm and trying to make a turn into a busy intersection, rather than having to focus on getting the gas pedal in just the right position when 2" of travel is the difference between 0 and 300 horsepower, it would be nice to have the engine's response scaled to the available traction so I can focus my attention on merging.
But for me, when I'm driving in a snowstorm and trying to make a turn into a busy intersection, rather than having to focus on getting the gas pedal in just the right position when 2" of travel is the difference between 0 and 300 horsepower, it would be nice to have the engine's response scaled to the available traction so I can focus my attention on merging.
Eric Law
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking
Be alert! America needs more lerts.
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking
Be alert! America needs more lerts.
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- Super MS/Extra'er
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Re: More sophisticated boost blending?
Unless you lock the waste gate and in the open position at low throttle positions, the lowest power you can make "On the spring". If that is too much power, it takes DBW to control these things correctly. What I do now is lock the BOV open when the driver is back pedaling he throttle.
see the TPS vs RPM on this motor before we got serious about controlling this stuff.
http://www.nbs-stl.com/miata/AccelWhenLifting.png
Andy
see the TPS vs RPM on this motor before we got serious about controlling this stuff.
http://www.nbs-stl.com/miata/AccelWhenLifting.png
Andy
Last edited by whittlebeast on Mon Nov 28, 2016 5:03 am, edited 1 time in total.
Re: More sophisticated boost blending?
Yeah but I'm running a fairly soft spring... "spring" boost is only about 8 PSI whereas "full" is around 22.
I actually have a plan if I ever get the time to make it even more controllable. With a 4-port solenoid valve, you can use boost pressure to *close* the wastegate as well as open it. That would allow use of an even softer spring but retain the ability to run high boost.
And I've thought about DBW too...
I actually have a plan if I ever get the time to make it even more controllable. With a 4-port solenoid valve, you can use boost pressure to *close* the wastegate as well as open it. That would allow use of an even softer spring but retain the ability to run high boost.
And I've thought about DBW too...
Eric Law
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking
Be alert! America needs more lerts.
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking
Be alert! America needs more lerts.
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- Super MS/Extra'er
- Posts: 2221
- Joined: Tue May 04, 2004 8:20 pm
- Location: St Louis
- Contact:
Re: More sophisticated boost blending?
Our motor was still making way too much power at 15% throttle and 8 lbs boost. Here is how I set up the BOV.
http://www.nbs-stl.com/miata/Dump_BOV.JPG
It works great. We did a vacuum accumulator with hardware store PVC pipe and a one way air valve in the hose.
Andy
http://www.nbs-stl.com/miata/Dump_BOV.JPG
It works great. We did a vacuum accumulator with hardware store PVC pipe and a one way air valve in the hose.
Andy
Re: More sophisticated boost blending?
Interesting!
I know a few modern cars use computer-controlled solenoids to switch vacuum to the BPV too. Some of the VAG cars even have electric BPVs!
I know a few modern cars use computer-controlled solenoids to switch vacuum to the BPV too. Some of the VAG cars even have electric BPVs!
Eric Law
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking
Be alert! America needs more lerts.
1990 Audi 80 quattro with AAN turbo engine: happily running on MS3+MS3X
2012 Audi A4 quattro, desperately in need of tweaking
Be alert! America needs more lerts.