DIY_EFI Digest Saturday, April 1 2000 Volume 05 : Number 133 In this issue: Re: Affordable Wideband ECUs - How to? RE: Affordable Wideband ECUs - How to? Wideband O2 control Re: Affordable Wideband ECUs - How to? Re: Affordable Wideband ECUs - How to? Re: Affordable Wideband ECUs - How to? Re: Ion current sensing -> spark advance Re: DIY_EFI Digest V5 #131 See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Fri, 31 Mar 2000 18:44:55 -0500 From: Will McGonegal Subject: Re: Affordable Wideband ECUs - How to? >From: garwillis@xxx.com (Garfield Willis) >Subject: Affordable Wideband ECUs - How to? > >You could see the AFR reading quickly respond as the FI settings were changed. > >Handy tools to have. >I expect you must have been holding significant load on the engine via >the dyno, in order to get it into open-loop. This is the normal tuning >mode for non-wideband controllers. The FI system on the test vehicle (not a road going vehicle) was an after market unit and O2 feedback was not being used on it. We were able to set the AFR for a variety of throttle/load/speed settings, including light loads, not just significant loads. A good way to get your initial FI computer map settings. Will - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Sat, 1 Apr 2000 03:00:41 +0200 From: =?iso-8859-1?Q?J=F6rgen_Karlsson?= Subject: RE: Affordable Wideband ECUs - How to? Well, I am sort of the tech assistant for a friend that has a fp. That usually mean that whenever he buys anything I am the one that plays with the stuff... He just installs it and drive the car. But the timing is a bit bad, he left for Florida two days ago. I am sure that I can scan a copy of the manual when he gets back, I hope that no fp guys are listening. The tuning software is available at their site. It was hell to find it and I have lost the link, I uploaded it to: ftp://ftp.diy-efi.org/incoming/cc_demo.zip I am sure that they dont mind. It is 297kb in size and works on win2000, I am not sure if it can connect to the ecu if run on w2k. On the 'dashboard' you can see a lot of info on the o2 sensor. I haven't looked at it much but I guess that it is for debugging sensors that act up. I think that everything can be datalogged. Our sensor and fp box is matched to each other, the sensor is marked with the serial# of the box. The first box we got was defective (or as I see it they sent the wrong box) and the box and sensor had to be returned. This can of course be a mistake from the guys that sold the stuff... Scott's observations strongly suggest that the sensor has a calibration resistor on its connector. I have noted that when the number in the VE table is to far from the correct number the o2 sometimes tend to oscillate. I think this happens when the value is more then 15-20% off and I think that it was only when the mixture was very rich (turbo rich). But this can of course be something about the car, syclones are pretty strange... Maybe it is the water injection (aquamist). This fp is bank to bank. BTW How much are the aquamist systems in the us? I think that I can get a good deal on them here. Jörgen Karlsson Gothenburg, Sweden - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Sat, 1 Apr 100 09:31:25 +0800 (WST) From: Bernd Felsche Subject: Wideband O2 control Garfield Willis writes: >(2) Q: what kind of interesting controller phenom do you get into if >you're actually building your own controller from scratch, have access >to the code, and want to equip it to run closed-loop WOT via wideband O2 >sensing. Seeing that the O2 is customarily used as an "error" device in the feedback loop, one could use the error output to adapt fuelling to changes in the engine itself. e.g. You don't have to manually re-program the operating maps for increments (one hopes) in airflow and fuelling. An extrapolation of that is that the ECU will be able to tell you if there was an improvement - it's an adjunct to a road-dynamometer function. With closed-loop control, we can also ensure that we're getting maximum power when required. At present, the fuelling assumes a certain engine condition and most likely, the actuall fuelling is too lean or too rich for maximum power. We can use lean-burn in a controlled manner (e.g. during cruise) to reduce fuel consumption. On the emissions side; knowing the amount of air pumped, we can determine the amount of "penalty" accumulated in an emissions cycle. So the engineer can not only control the amount of emissions outside of the cat. conversion window, but also take subsequent measures to ensure that the engine operates within the permissible limits for the entire cycle... it may be considered "cheating" by some, but then so is choosing appropriate gear ratios! It's not like we're deliberately recognizing the emission cycle and operating in a compliance mode. "Ideal" AFRs are well known; for performance, emission (usually in conjunction with cat. convertors, EGR, secondary air pump, etc) and fuel consumption. A completely-different sort of ECU, using for example neural networks (NN) would make it easier to adapt to any engine given just a tiny subset of operating parameters. The ECU's NN then alters the controllables to achieve the required goal(s). I understand that research is already under way with that approach. - -- Real Name: Bernd Felsche Email: nospam.bernie@xxx.au http://www.perth.dialix.com.au/~bernie - Private HP - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Fri, 31 Mar 2000 17:45:25 -0800 From: garwillis@xxx.com (Garfield Willis) Subject: Re: Affordable Wideband ECUs - How to? On Sat, 1 Apr 2000 03:00:41 +0200, Jörgen Karlsson wrote: >Our sensor and fp box is matched to each other, the sensor is marked with >the serial# of the box. The first box we got was defective (or as I see it >they sent the wrong box) and the box and sensor had to be returned. This can >of course be a mistake from the guys that sold the stuff... Scott's >observations strongly suggest that the sensor has a calibration resistor on >its connector. Yes, it sounds like they've left the cal resistor there, but they AREN'T bound to look at it electrically, and could easily have a mfg. step where they burn that info into the controller board manually, so you can't change the sensor without their help. This would be a sad manuever, but totally possible. Other AFR meter mfgs. burn both the cal and the transfer curve into EPROM, so you also are stuck with sending the whole thing back to them if you need a replacement sensor. You can argue with the business ethics of this, but the thing that burns me about "property" techniques like this the most is technical: it prevents people from swapping out the sensor vrs. controller to isolate a suspected failure to either controller or sensor. NTK is the same frigging way; you have a failure and want to send it back to them for testing to tell you just WHAT has failed, sensor or interface?, and they want to charge you, get this, "engineering bench time", which they of course point out is going to be WAY too spendy for you, so they insist you'd be better of to buy a whole new replacement box and sensor instead (deduct $1000 from you bank account; do not pass GO). Cute, huh? >I have noted that when the number in the VE table is to far from the correct >number the o2 sometimes tend to oscillate. I think this happens when the >value is more then 15-20% off and I think that it was only when the mixture >was very rich (turbo rich). But this can of course be something about the >car, syclones are pretty strange... Curious, but somehow I doubt it's engine-specific. Sounds like controller instability, perhaps from poorly set/tuned controller parameters or phase lag from distance of O2 bung to exhaust ports. Just wild guesses, really. But delays in a feedback situation can really snag ya. Thanks for the additional insights. Gar - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Fri, 31 Mar 2000 19:25:15 -0800 From: garwillis@xxx.com (Garfield Willis) Subject: Re: Affordable Wideband ECUs - How to? On Fri, 31 Mar 2000 13:43:25 -0700, Chad wrote: >I have a unit up and running right now that does exactly that, allow the >user to change the stoich point that the O2 sensor reports. It works quite >well, and you can watch the A/F change as buttons to rich/lean are >pushed. The flaw in getting the ECU to continually run in closed loop is >that this is only manipulating a control input. In effect, you are *asking* >the ecu to change the pulse width to the injectors rather than forcing it >to run in a certain way. The changes only occur at idle and cruise, when >the ecu is paying attention to the O2 signal input. With the experimenting >I've done, I agree that you need to have more authority (source code) in >order to force the ecu to do what you want it to. Hey Chad. Yeah, I agree the hard part isn't the simulation of a switch-type O2 sensor, tho I wouldn't diminish the usefulness of that; good experiment. As you say, just controlling the stoich switch-point is "pushing on a string". We need much more forceful measures. But there ARE (I understand from them-what-nose :) some params on some ECUs regarding the TPS and load limits (not to mention temp inputs) where you can say "thou shalt go to open-loop". The hope was that by constraining these, you could effectively TELL (not ask) the ECU to be in closed-loop, I guess by process of elimination. There would still be lots of situations like cold-crankNstart, warm-up, etc. where you'd want to be running outta tables, but the real critical question is whether you can TELL the ECU during major TPS and load regimes to "stay in closed-loop". I'm probly dreamin to think it could ever be that straightforward; but it's just so damned 'desirable' to imagine being able to fashion the OEM ECUs into closed-loop controllers that I'm probly in denial right now about the doability, and still clinging to a mere thread of hope that it could still in some way be possible. Being able to say "anti-gravity" doesn't make it any easier; but ya gotta have dreams. :) Gar - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Sat, 1 Apr 2000 11:24:04 +0200 From: "Espen Hilde" Subject: Re: Affordable Wideband ECUs - How to? Hi ! We have to measure the IONs in the combustion flame.........thanks I was a little conserned what the ions could do with EGOR.... Thinking loud again..... The EGOR could have a PC connection with a AFR map ,fill in the desierd AFR and drive .We have to have RPM and a MAP sensor . Maybe the ecus of our cars is going not to be possible to hack anymore, then our option is outside manipulation,or changing ecu. If we want full controll without forcing the ecu into closed loop we could add mili sec directly to the injectors or electronicaly controll the fuel pressure with a add on PWM valve.Mostly the reason for canging cal is to increase the hp.A PWM valve will give us more fuel to play with. Espen - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Sat, 01 Apr 2000 02:34:16 PST From: "mike mager" Subject: Re: Ion current sensing -> spark advance David DeHaven asked about my reply to the "Ion current sensing -> spark advance" thread: >I'm researching a way to use ion current sensing to determine the PPP. Oh, yeah, I got that, but when I asked . . . "You have been thinking about pressure measurements, any conclusions (besides cost)?" . . . I was wondering what you had concluded about using mechanical sensors for reading pressure (such as used in the big basic engine research laboratories). >There are other things I want to use it for, but that's the main >application. The other is knock detection. I know it, and I sure wish that I just had it done, but, well, we're making progress (through you, thanks!). I said . . . "I am working with very little information about the 'DeSaxe cylinder offset', also known as an 'offset cylinder engine'; I wonder about enough offset to give a vertical connecting-rod at the PPP." . . . and you replied . . . >So, basically, the crank centerline is not lined up with the center of the >piston? . . . Yes, that's just it in the 'offset engine' or DeSaxe offset cylinder; the connecting-rod angle is altered at certain (each) point(s) in the stroke; as much as I can tell, the connecting-rod is allowed/made to be vertical somewhere near the PPP, rather than being at an angle, so the vector would be just down, and not partly (wearing, frictioning) against the cylinder wall; speedway motorcycles and some modern automotive engines (and many old engines) use this, but I still haven't found a really good detailed explanation of it (and I've been looking in many old books!). Now, note that this doesn't apply directly to ICS, but, it seems (to me) related enough that a guy might want to address the mechanicals (if we are designing - or bench racing about designing - engines), as well as the fueling and ignition. > > gudgeon-pin offset, which is still desired. At the least, the DeSaxe >offset appears to noticeably reduce piston friction during the power >stroke. >Or the piston pin is offset from center (for normal engines). Makes sense, though it seems you could end up wearing one side of the cylinder wall more than the other. The pin offset causes the piston rock (evident in all typical reciprocating-piston engines) to go in one step of the skirt touching, then the next step of the crown touching, as opposed to one big 'slap' step; the old Hot Rod Magazine trick of installing the stock OEM (offset pin) pistons _backwards_, does the opposite - giving horrendous slap! - but reduces the friction for drag racing. One more example of 'engineering, the art of compromise'. >As long as you know where the PPP should be, the method of calculating the >spark advance is no different. This setup just takes uses the power stroke >more efficiently. >-DrD- Oh, yeah, got it (at least on a cursory level); sure do wish that I just had it an a form to experiment with; well, some day, one more project . . . We sure value your input on this, Mike ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Sat, 01 Apr 2000 03:00:55 PST From: "mike mager" Subject: Re: DIY_EFI Digest V5 #131 Thanks! Saved as a 'favorite'! Mike >From: "John Dammeyer" >Reply-To: diy_efi@xxx.org >To: >Subject: Re: DIY_EFI Digest V5 #131 >Date: Fri, 31 Mar 2000 12:44:08 -0800 > >Hi, > >I don't remember where I found the Al Grippo document nor what his email >address is but >what I have done is posted the document on my WEB page under the documents >link. It's the >only one there at the moment. One of these days I'll add other documents >of interest. > >www.autoartisans.com > >Cheers, > >John > > > > ------------------------------ > > > > Date: Thu, 30 Mar 2000 23:45:54 PST > > From: "mike mager" > > Subject: Re: 8051 Code > > > > Greetings! > > > > I searched around for Al Grippo code and for Al Lipper code, with no >result; > > how could I find it? Circuit Cellar I have, and that's what starterd >my > > interest in a DIY system. > > > > Thanks, > > Mike > > >---------------------------------------------------------------------------- >To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the >quotes) >in the body of a message (not the subject) to majordomo@xxx.org > ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ End of DIY_EFI Digest V5 #133 ***************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. 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