EBC mod - Writeup - Page 4 - Miata Turbo Forum - Boost cars, acquire cats.

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Old 08-13-2007, 02:31 PM   #61
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Those settings werent' defaults of any kind. Default = Off
I made them up semi-aribitrarily to test for closed loop functionality.

Savington, you need to take the 6 seconds to calibrate the TPS. :smack:

In the absense of closed loop data, the MS will run open loop. If you add closed loop data in, then it will try to run closed loop, as long as your duty cycle targets are ballpark to the boost targets. I haven't played with tuning or autotuning the boost targets, but in there somewhere an autotune function and a 3D boost table. Just haven't screwed with it yet.
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Old 08-13-2007, 03:02 PM   #62
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So you have to set up both of the tables to use the Duty Cycle table? I'm a bit confused.
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Old 08-13-2007, 03:12 PM   #63
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Open loop boost control uses the duty cycle table. Closed loop boost control utilizes a control algorithm to minimize the difference between resulting boost from the duty cycle and the kpa target table. If the boost level, controlled by duty cycle, is out of range of the kpa target (that range defined by the closed loop kpa limit), than the closed loop feedback controller gives up and you revert all control back to the duty cycle table.
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Old 08-13-2007, 03:20 PM   #64
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So I can just set the closed loop limit to like 200 and rely entirely on the duty cycle tables?
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Old 08-13-2007, 05:26 PM   #65
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Durr. Not 200, 0.

There's a problem, though: The closed loop KPA limit won't allow itself to be set to 0, only numbers 20 or larger. Should I just set the boost KPA targets to some stupidly high number (250kpa everywhere?), and then leave the closed loop limit at 20? I'm never seeing higher than 196kpa right now, and my goal is to mimic the MBC boost curve to start, so setting all the KPA targets stupid high and leaving the limit at 20 should keep enough of a buffer to allow the MS to always use the duty cycles.

Right? :(
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Old 08-13-2007, 05:38 PM   #66
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Sounds like it'd work decently, but I might try putting the kpa targets quite a bit lower than you will get, maybe like 130kpa, just for safety. You'll more than likely blast past that kpa target before the closed loop ebc will kick in, and once you're beyond 150kpa, you're in the clear for duty cycle only. Just an alternative thought.
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Old 08-14-2007, 05:26 AM   #67
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Can I go to more than 100% duty cycle? :gay: This curve is getting me 13.5-14psi to 5500rpm, tapering to around 12psi at redline. Used to be 13psi, tapering to 9.5 at redline. (use my **** and you'll blow yours up, etc)
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Old 08-14-2007, 07:40 AM   #68
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Why not try 100% DC at the bottom range, until just before you reach peak boost? That's how you would emulate the MBC; keep the wastegate closed until you reach your desired boost. Then modulate it with a lower duty cycle.
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Old 08-14-2007, 09:09 AM   #69
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100% duty cycle at 7200rpm
get yourself a new actuator, or at the very least a helper spring.
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Old 08-15-2007, 03:16 AM   #70
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Quote:
Originally Posted by Atlanta93LE View Post
Why not try 100% DC at the bottom range, until just before you reach peak boost? That's how you would emulate the MBC; keep the wastegate closed until you reach your desired boost. Then modulate it with a lower duty cycle.
That's the next step. I'm not going to do that until I get the new turbo, though. (GT2554R)
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Old 08-15-2007, 09:03 AM   #71
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that's just silly. go ahead and do it--you might like it
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Old 08-15-2007, 10:02 AM   #72
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Are you MS guys using the GM solenoid seeing boost fluctuation during open loop when the weather changes? I've got a Motec and am messing with boost control. I'm using open loop now to figure out the right duty cycle and will then move to closed loop when I have that figured out. It seems that in colder weather I'm getting a 1-2 psi greater boost reading than when it gets hot outside. That's at about 20 degrees cooler.

Thanks,
Frank
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Old 08-15-2007, 02:55 PM   #73
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If 100% isnt rasing the boost enough, change 19.5 Hz to 13Hz, should shift the entire range up/down....


FWIW Savington, to spool faster change to first two columns to something like this:



so the solenoid is always closed below your boost target for the fastest possible spool, then I give it 200RPM to reach the point where I make my peak boost and I limit it there.

If you look at your 3D map, or your logs of your DC duriong spool, the solenoid is slowly opening as your are trying to spool, which is exactly what you DONT want to do.
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Old 09-06-2007, 01:21 PM   #74
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Wonder if I could get away with using a 1n4001 diode instead. I have three left over from my MSI build because I didn't do the unnecessary circuits.
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Old 09-06-2007, 01:28 PM   #75
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sniff, how do you do this for MSPNP?
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Old 09-06-2007, 01:34 PM   #76
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how do you do what? use ebc? plug it in
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Old 09-06-2007, 01:36 PM   #77
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Pretty sure the PNP has it built in already, do you need the center connector to do it?
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Old 09-06-2007, 01:37 PM   #78
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yes :(

Seriously? No wiring or anything?
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Old 09-06-2007, 01:44 PM   #79
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well yeah, don't be a dumbass, you're going to have to run 2 wires. one for +12V and the second to the center plug on the PNP.

i have a picture somewhere...
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Old 09-06-2007, 01:47 PM   #80
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Ben. I am a dumbass lets not be confused about that.

Im ok running wires, i didnt want to tear open my pnp

Does anyone else love jerry inappropriately?

Do basically we just need the high speed solenoid and junk
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