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Old 06-23-2010, 08:58 AM   #161
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That's correct. You can set the controller to output either an NA CAS signal or an NB cam/crank signal to the MS. In other words, you won't have to change a thing on your MS if you're currently using a CAS and furthermore, won't have to build any additional hardware.
I would then assume that if you have it send out a NA CAS signal it will actually be more correct then the stock NA CAS gives correct?

I have dibs on the first one out of production. You can have my first born daughter.
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Old 06-23-2010, 11:28 AM   #162
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I would then assume that if you have it send out a NA CAS signal it will actually be more correct then the stock NA CAS gives correct?

I have dibs on the first one out of production. You can have my first born daughter.
The "jitter" produced by the stock CAS is eliminated. From there you're at at the mercy of the OE 4 tooth crank wheel which is a lot more "quiet" comparitively speaking.

Unless she's 27 and single, I'll pass .
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Old 06-23-2010, 01:04 PM   #163
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The "jitter" produced by the stock CAS is eliminated. From there you're at at the mercy of the OE 4 tooth crank wheel which is a lot more "quiet" comparitively speaking.

Unless she's 27 and single, I'll pass .
She is unborn, so you might have to wait a while.

I got the whole setup to convert to the Crank and Cam sensors for my VVT motor, I am just to lazy to build the circuit for my MS to understand the signals. So by giving you cash money it saves me energy which is win-win.
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Old 07-07-2010, 11:11 PM   #164
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So, any updates so far Kevin?
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Old 07-08-2010, 03:39 PM   #165
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So, any updates so far Kevin?
The bootloader problem is solved which was really the only hold up from release. I'll be finishing up a bit of testing today and tomorrow and will be making a few phone calls next week.
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Old 07-15-2010, 03:48 PM   #166
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this is awesome planning my vvt swap this fall in my 1990 csp car


Last edited by tzdevill; 07-15-2010 at 04:00 PM.
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Old 07-15-2010, 03:49 PM   #167
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The bootloader problem is solved which was really the only hold up from release. I'll be finishing up a bit of testing today and tomorrow and will be making a few phone calls next week.
Sooooo. Any word on those phone calls?
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Old 07-16-2010, 10:59 AM   #168
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The controller and software are complete. I have a lunch meeting today to discuss methods of getting this out to the masses.
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Old 07-16-2010, 11:42 PM   #169
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The controller is away to DIY AutoTune for an initial installation and testing! If all goes well, we'll be ordering parts and have these buggers out to you guys soon.
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Old 07-21-2010, 03:51 PM   #170
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This is really great news, Kevin and everyone who has done this research and foot work A VERY BIG THANK YOU!
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Old 12-08-2010, 06:19 PM   #171
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On the topic of the original post, I'm curious about implementing this as an open loop setup.

I can make a simple 6x6 78Hz (that's the limit on generic outputs) output table and assign it to controlling VVT.

if I wanted to emulate essentially what I discovered (full retard to 2700, full advance 2700-4700, full retard above 4700), would it be as simple as dumping the duty cycles Jason came up with on page fourish....
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Valve will be at rest (retard) position at 300 mA - ~16% duty cycle at 14V
Valve will be at endstop (advance) at 900 mA - ~48% duty cycle at 14V
Valve is centered in "lock" position at 530 mA - ~28% duty cycle at 14V
... into the table at the appropriate RPM? I'm thinking of something like this:
Code:
kPa
250   0     0     60    60    0     0  
180   0     0     60    60    0     0  
120   0     0     60    60    0     0  
 80   0     0     60    60    0     0  
 60   0     0      0     0    0     0  
 20   0     0      0     0    0     0  
      500  2600  3000  4200  4700  8000 RPM
I'm assuming the minimum and maximum duty cycle isn't critical as long as I am below or above them enough to overcome hysteresis. And obviously the "lock" position without closed loop is meaningless.

The only thing I can think that might make a difference is providing a larger RPM gap for the transition from 0 to 60% or 60 to 0, but perhaps I will just try to log the rate of change and see if it's "too fast".
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Old 12-08-2010, 06:23 PM   #172
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No dice, I tried it using my own implementation of an open loop controller and it didn't go very well.
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Old 12-08-2010, 07:08 PM   #173
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No dice, I tried it using my own implementation of an open loop controller and it didn't go very well.
Bummer. I mean it's essentially the same as supplying 12V and GND to the spool valve to advance, correct?

No luck at all?

If not, I will just keep pasting the contents of this thread into msextra.com/forums
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Old 12-08-2010, 07:14 PM   #174
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No luck at all. I didn't have a means to measure the actual cam advance/retard, but the feeling was that there wasn't any gain, and I would sometimes get a weird idle, low-speed surging/bucking, the works.
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Old 12-08-2010, 09:35 PM   #175
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It is not possible at all to target any cam phase other than full advance and full retard without closed loop control.
Basically the cam phase is equal to the integral of (the current minus the hold current, plus a random variable, plus hysteresis). Until it hits full advance or full retard.
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Old 12-08-2010, 11:12 PM   #176
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I only want full advance or retard for now. basically one end or the other of the adjustment.

I understand that the cam advances as long as current is high enough / duty cycle is over a threshold. I also understand that I do nothing and it will retard fully.

So... why wont providing more than the current/duty move the spool valve to the position where oil fills the advance chamber?
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Old 12-09-2010, 01:50 AM   #177
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the greater the current is over the threshold, the faster it moves to the full advance position.
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Old 12-09-2010, 03:07 AM   #178
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I only want full advance or retard for now. basically one end or the other of the adjustment.
Oh that will work then. Why would you want to do that anyways?
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Old 12-09-2010, 10:49 AM   #179
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Oh that will work then. Why would you want to do that anyways?
Based on my dyno testing, I'll get >80% of the benefit.
(dont make me post that dyno plot again...)
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Old 12-09-2010, 01:15 PM   #180
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Do your worst!
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