DIY_EFI Digest Sunday, April 9 2000 Volume 05 : Number 141 In this issue: Re: Valve seats Re: cold engine driveability, fuel pressure Re: MAF sensor impedance Re: C/L WB/WOT OEM ECUs... 87 TPI Fuel Pressure Setting Re: 87 TPI Fuel Pressure Setting Re: 87 TPI Fuel Pressure Setting Re: MAF sensor impedance GM ECU for Turbo Motorcycle? GM ECU for Turbo Motorcycle? Re: C/L WB/WOT OEM ECUs... ONE WIRE O2 TO HEATED O2 Re: C/L WB/WOT OEM ECUs... Re: C/L WB/WOT OEM ECUs... Re: C/L WB/WOT OEM ECUs... Re: ONE WIRE O2 TO HEATED O2 Re: C/L WB/WOT OEM ECUs... RE: C/L WB/WOT OEM ECUs... Re: C/L WB/WOT OEM ECUs... Re: GM ECU for Turbo Motorcycle? Re: C/L WB/WOT OEM ECUs... Re: C/L WB/WOT OEM ECUs... RE: C/L WB/WOT OEM ECUs... See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: 9 Apr 2000 1:47:33 +1200 From: "Tom Parker" Subject: Re: Valve seats Ade + Lamb Chop wrote: >Go along to your local machinist and ask how much it would cost to get hard >valve seats fitted you only need the exhaust seats done. I was quoted about >20ukp per seat. If you are running CR too high for 95ron UL then will need >to run super UL or LRP as they both have almost the same Ron but LRP is >cheaper and a lot more available. However you must be aware the hardened valve seats are not completely reliable. They can and sometimes do fall out. It is probable that you will loose the head, piston, maybe the block, or worse the crank and gearbox (as happened to one person's 1071S mini in New Zealand). Use a good machinist. - -- Tom Parker - parkert@xxx.nz - http://www.geocities.com/MotorCity/Track/8381/ - ---------------------------------------------------------------------------- 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, 8 Apr 2000 07:23:42 -0700 (PDT) From: Carter Shore Subject: Re: cold engine driveability, fuel pressure Franc Buxton wrote: > .. Injector flow is to a large extent proportional > to fuel pressure. I have done this on my Rover > Metro (UK), fitted with a 1.8-litre engine in place > of the 1.4 and using the 1.4 engine management. > ... Fuel pressure increase in this particular case > was from 3.2 bar to 4.75 bar, surprisingly somewhat > more than the proportional difference in capacity, > but that's what it needed. ... I have literature that describes the injector flow rate increase as proportional to the square root of pressure increase, ie, to double the flow, use four times the pressure. In your example this gives: 1.8/1.4 = 1.28 -- displacement increase ratio (1.28) * (1.28) = 1.65 -- fuel pressure increase ratio 3.2 bar * 1.65 = 5.28 bar -- fuel pressure in bar Of course, this number does not match what you obtained for proper operation, so much for theory! I'm looking at a similar situation, running a 1.5L motor with EFI calibrated for 1.9L. In my case, I plan to select smaller flow injectors, then diddle the fuel pressure if needed to fine tune. Once running, I will hack the spark and fuel tables. BTW, what method did you use to adjust the fuel pressure? Thanks, Carter Shore __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.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, 08 Apr 2000 10:25:24 -0400 From: David Cooley Subject: Re: MAF sensor impedance At 08:00 AM 4/8/00, you wrote: > Does anyone know the output impedance for a Ford MAF sensor? Or >perhaps where I might find this information? Well, Not sure what the Impedance is, but it's a voltage from approximately 0.1V at low flow (idle) to ~4.8V at full flow =========================================================== David Cooley N5XMT Internet: N5XMT@xxx.net Packet: N5XMT@xxx. Member #7068 We are Borg... Prepare to be assimilated! =========================================================== - ---------------------------------------------------------------------------- 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, 8 Apr 2000 10:33:40 -0400 From: "nacelp" Subject: Re: C/L WB/WOT OEM ECUs... All I see there is Accleration Enrichment. I may be spacing it, but just done't see it You are clear (?) that you'll have to have the EGOR output voltages for O2v swing over, and under the O2 cross over reference settings in the ecm. By example. The WB is Looking for a average of what would be a .8v normal O2 voltage. The ecm needs to see a signal that swings over about .6, and drops below .3v as something that it understands, I don't think it will understand a fixed .2v other then to set a code. You might want need to introduce a tach reference pulse into the EGOR before your done with things. Just so there is some easy to see O2 variations, (ie easy for the computer to see, and maintain a sample rate that it likes). Note 2: We know the ecm needs to shoot for a 14.7 for the EPA. So we also know what 14.7 is for EGOR. Then using those numbers we can set the kluge to generate a over/under O2 signal for the ecm to get that. Meaning right output based on EGORs voltage. This is what you've already mentioned, just a converter to run a oem ecm, with EGOR. The big advantage I see here is that for none cat applications, can trash the 14.7 and go for min fuel consumption. With that info., generate a DC based on the under/over voltages the ecm will like, and then it will do the AFR calc.. That is the trick for EGOR as I see things, While some of the above may seem odd, it's stuff that came to light on the ecm bench. The ref pulse tach made some early O2 feedback testing even possible when, I'd been fighting code 13-44-45s. I've sleep since then so bear with me about this is how I remember it. Just ya gotz to start somewhere. Grumpy > Oh yah, it's in there. Run CalCom, load the demo file (you have to load > the demo file, or otherwise, those tables aren't visible), then look at > the "VE or Fuel" screen/button. You'll see tables/maps for all three. > >Yes, that can be done code wise, but I was offering an alternative for those > >without hac'd ecm applications, and those that don't care to don't wan to do > >much prom editing. > Yeah, when I said flag/column in the tables, I meant in the CAL tables. > >Course this is all theory till we get things up and running <<>>.... > >Just need to get a EGOR to use forra while > Patience, they'll be available soon; then you can play to your heart's > content. But we have to have some inkling of what is possible, in order > to prepare the proper App Notes for switch-type O2 simulation. That's > why I'm bird-dog'ing this topic now. It's hard to figure out for all OEM > ECUs what's required to "pretend I'm your switch-type O2 sensor". So I'm > interested in preparing instructions for the most common and most > promising OEM ECUs; hoping those will be the GM ecms. > 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, 08 Apr 2000 09:57:08 -0500 From: "Todd Burkard" Subject: 87 TPI Fuel Pressure Setting Does anyone know the Stock fuel pressure setting on a 87 Iroc With a 305 TPI motor I put a adjustable fuel pressure Regulator on and it is running a little Fat. I needed to increase the fuel pressure to compensate for the increase from a 305 to a 327 but I bought the system in parts and I put the Adjustable regulator on as I was putting it together and none of my manuals gives a setting so I set it at about 50 PSI to start. Even some formulas for calculating what it would be would be fine I have a Big Calculator ;) I am in the process of coming up with a new Chip for it and another project (Can never have just one going) but I need to figure out the chip stuff first, but any suggestions on what to add there also would be fine. Thanks, Todd - ---------------------------------------------------------------------------- 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, 8 Apr 2000 11:08:59 -0400 From: "nacelp" Subject: Re: 87 TPI Fuel Pressure Setting I start at 43ish. Just a few minutes driving anf the B/L tells me which way to go. Don't really assume much on fuel pressures. They are so eninge specific. I've seen 305 injectors in a 350 that wound up perfectly happy at 38 PSI. (after chip work). Grumpy > Does anyone know the Stock fuel pressure setting on a 87 Iroc With a 305 TPI motor I put a adjustable fuel pressure Regulator on and it is running a little Fat. I needed to increase the fuel pressure to compensate for the increase from a 305 to a 327 but I bought the system in parts and I put the Adjustable regulator on as I was putting it together and none of my manuals gives a setting so I set it at about 50 PSI to start. Even some formulas for calculating what it would be would be fine I have a Big Calculator ;) > > I am in the process of coming up with a new Chip for it and another project (Can never have just one going) but I need to figure out the chip stuff first, but any suggestions on what to add there also would be fine. > > Thanks, > Todd > > -------------------------------------------------------------------------- - -- > 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 > - ---------------------------------------------------------------------------- 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, 8 Apr 2000 10:05:59 -0500 From: "Dan Plaskett" Subject: Re: 87 TPI Fuel Pressure Setting The 5.0 (305) injectors are 19lb/hr @xxx.7 (350) injectors are 22lb/hr @xxx.5psi Dan Plaskett - ----- Original Message ----- From: "Todd Burkard" To: "<" Sent: Saturday, April 08, 2000 9:57 AM Subject: 87 TPI Fuel Pressure Setting > Does anyone know the Stock fuel pressure setting on a 87 Iroc With a 305 TPI motor I put a adjustable fuel pressure Regulator on and it is running a little Fat. I needed to increase the fuel pressure to compensate for the increase from a 305 to a 327 but I bought the system in parts and I put the Adjustable regulator on as I was putting it together and none of my manuals gives a setting so I set it at about 50 PSI to start. Even some formulas for calculating what it would be would be fine I have a Big Calculator ;) > > I am in the process of coming up with a new Chip for it and another project (Can never have just one going) but I need to figure out the chip stuff first, but any suggestions on what to add there also would be fine. > > Thanks, > Todd > > -------------------------------------------------------------------------- - -- > 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 > > - ---------------------------------------------------------------------------- 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, 08 Apr 2000 23:45:14 From: "Mike (Perth, Western Australia)" Subject: Re: MAF sensor impedance At 10:25 AM 8/4/2000 -0400, you wrote: >Well, >Not sure what the Impedance is, but it's a voltage from approximately 0.1V >at low flow (idle) to ~4.8V at full flow If you are worried about loading it with whatever circuit you are driving, then just feed it into an opamp in unity gain mode - that has at least a 1meg input impedance. Given the type of cables used for MAPs I would very much doubt they have any more then 10K output impedance, an opamp will buffer the output quite a bit - use an LM747 or equivalent... Rgds 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 ------------------------------ Date: Sat, 08 Apr 2000 08:45:52 PDT From: "Steve Leonard" Subject: GM ECU for Turbo Motorcycle? I'm building Kawasaki ZX-11 motorcycle with a Aerocharger turbo, max engine RPM is 11,000. Is there a GM ECU that I could adapt to this project? cheers Steve L. ______________________________________________________ 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, 08 Apr 2000 08:45:52 PDT From: "Steve Leonard" Subject: GM ECU for Turbo Motorcycle? I'm building Kawasaki ZX-11 motorcycle with a Aerocharger turbo, max engine RPM is 11,000. Is there a GM ECU that I could adapt to this project? cheers Steve L. ______________________________________________________ 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, 08 Apr 2000 09:18:34 -0700 From: garwillis@xxx.com (Garfield Willis) Subject: Re: C/L WB/WOT OEM ECUs... On Sat, 8 Apr 2000 10:33:40 -0400, "nacelp" wrote: >All I see there is Accleration Enrichment. I may be spacing it, but just >done't see it Right, that's what I was referring to. Are you saying those don't imply O/L? >You are clear (?) that you'll have to have the EGOR output voltages for O2v >swing over, and under the O2 cross over reference settings in the ecm. Yes, simulating the switch-type O2 sensor gives you the same phenom as before; the controller criss-crosses that simulated stoich point. There are lots of details to determine on the bench/road, tho. How tightly this "fooled" controller will keep to within the set-point (the AFR you have set as the new "stoich") is one question. When these controllers hunt around real stoich, they overshoot some on either side. This slop has to be taken into account when tuning this type of "fooled" controller. >Note 2: >We know the ecm needs to shoot for a 14.7 for the EPA. So we also know what >14.7 is for EGOR. Then using those numbers we can set the kluge to generate >a over/under O2 signal for the ecm to get that. Meaning right output based >on EGORs voltage. This is what you've already mentioned, just a converter >to run a oem ecm, with EGOR. The big advantage I see here is that for none >cat applications, can trash the 14.7 and go for min fuel consumption. With >that info., generate a DC based on the under/over voltages the ecm will >like, and then it will do the AFR calc.. That is the trick for EGOR as I >see things, Yup, as you suggest above, you could also use the same scheme intended to fix a nice well-controlled rich mix at WOT, to also home in on some lean cruise AFR when lightly loaded. You can imagine a spectrum of AFR setpoint repertoire, depending on how complex you wanna get: (1) Go to "C/L precision rich" above a certain TPS, otherwise keep to real stoich. [Unless of course you go to O/L during all the aforementioned "special" conditions like cold-start/warmup, sensor failure, etc.] (2) Same as above, but replace "real stoich" with some other economy setpoint, hopefully not too lean. :) (3) Get crazy and "map" the TPS to a table of target AFRs. Now you have as fine a control over the AFR as you have table space. You don't even have to go digital here; you could make a simple piecewise linear curve with a few op-amps, instead of table look-up, to create a rough curve of TPS vrs AFR that the simulated O2 should follow. OTOH, this might be the point of departure for including a proc into your O2 simulator circuit; depends on how much you love/hate analog. :) (4) Get crazier yet and tap into the MAP signal, 2-D map both TPS and MAP to a table of commanded AFRs. Now you have C/L AFRs that depend both on throt and load. Woohee. Now you're starting to put nearly as much smarts in that lil goiter that's fooling with the simulated stoich point, as you have in the OEM controller. So you're approaching the point at which you might as well just bite the bullet and create a custom controller, and dump the OEM brain-stem? Well, maybe not quite, but you getmedrift. Depends on how much you wanna play with the electrics. 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, 08 Apr 2000 11:32:24 -0500 From: "Todd Burkard" Subject: ONE WIRE O2 TO HEATED O2 Just a quick question. Has anyone converted the one wire O2 Sensor in their GM EFI system to Heated O2 design I having a problem with going into open loop when I come to a stop because the O2 cools off to much being in my Header and I can't move it anyplace else. If you have could you give me a little insight on what it entails. Thanks, Todd To many projects to little time :) - ---------------------------------------------------------------------------- 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, 8 Apr 2000 13:56:24 -0400 From: "nacelp" Subject: Re: C/L WB/WOT OEM ECUs... > >All I see there is Accleration Enrichment. I may be spacing it, but just > >done't see it > Right, that's what I was referring to. Are you saying those don't imply > O/L? They have nothing to do with O/L C/L, think of that as just an acclerator pump, and little squirt of gas to cover sudden throttle movements. Got to think about your other stuff, more later Grumpy - ---------------------------------------------------------------------------- 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, 08 Apr 2000 13:03:09 -0700 From: garwillis@xxx.com (Garfield Willis) Subject: Re: C/L WB/WOT OEM ECUs... On Sat, 8 Apr 2000 13:56:24 -0400, "nacelp" wrote: > >> >All I see there is Accleration Enrichment. I may be spacing it, but just >> >done't see it >> Right, that's what I was referring to. Are you saying those don't imply >> O/L? > >They have nothing to do with O/L C/L, think of that as just an acclerator >pump, and little squirt of gas to cover sudden throttle movements. OK, this is *good*. If you're saying that such AE transients don't cause a mode switch, but just do a temporary blast of enrichment, and let whatever mode the controller is in roll on ahead, that's great. That means these same enrichments would occur even if we're in our new "C/L precision rich AFR" mode during high TPS. If there is further rateOchange AE on the TPS because we went from say high TPS to full WOT, then we still get this further enrichment transient, and then settle back down to our C/L commanded AFR again. That's even better than I had hoped. Moto bene. 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, 08 Apr 2000 17:14:25 From: Bob Tom Subject: Re: C/L WB/WOT OEM ECUs... At 01:03 PM 4/8/00 -0700, you wrote: >On Sat, 8 Apr 2000 13:56:24 -0400, "nacelp" wrote: >>> >All I see there is Acceleration Enrichment. I may be spacing it, but just >>> >done't see it >>> Right, that's what I was referring to. Are you saying those don't imply >>> O/L? > ...If you're saying that such AE transients don't cause >a mode switch, but just do a temporary blast of enrichment, and let >whatever mode the controller is in roll on ahead, that's great. ... >Gar That's is also my understanding on how AE is on the Chrysler PCMs as well ... still in C/L. BTW, Chrysler uses the term, Power Enrichment. Bob. Southern Ontario, Canada. 97 Dakota CC Sport,5.2L,3.55SG, auto.,4x2: best 14.917s, 90.78mph 85 Shelby Intercooled Turbo Charger,2.2L,5-spd man. 78 B100 Dodge van, '69 340-4bbl 70 Challenger,383-4bbl,slap-stik auto.,3.23SG,hemi orange,46,700 orig.mi. - ---------------------------------------------------------------------------- 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, 08 Apr 2000 19:14:58 -0400 From: Seth Subject: Re: ONE WIRE O2 TO HEATED O2 someone correct me if I am wrong, but if you just drop in a 3 wire and supply 12v to the heater wires, you should be all set. Someone poster earlier that the heater wires are usually the same color, while the sensor wire is a different color. - -Seth Todd Burkard wrote: > > Just a quick question. Has anyone converted the one wire O2 Sensor in their GM EFI system to Heated O2 design I having a problem with going into open loop when I come to a stop because the O2 cools off to much being in my Header and I can't move it anyplace else. If you have could you give me a little insight on what it entails. > > Thanks, > Todd > > To many projects to little time :) > > ---------------------------------------------------------------------------- > 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 - ---------------------------------------------------------------------------- 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, 08 Apr 2000 18:28:45 -0700 From: Doug Dayson Subject: Re: C/L WB/WOT OEM ECUs... Thoroughly appreciating this thread everyone but here's a Newbie's question... Is WB O2 closed loop control at WOT actually safe? I was just thinking that any fouling and/or other malfunction of the O2 sensor etc could result in you going way lean under load with catastrophic results... I'm thinking that you would need to have a "WOT Limp To The Finish Line" mode so perhaps you shouldn't disable the open loop stuff...rather have it take over if WB O2 output falls out of a pre-determined range for WOT or something like that... What say you knowledgeable folks? Doug - ---------------------------------------------------------------------------- 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, 8 Apr 2000 21:50:54 -0400 From: "the Fredericks" Subject: RE: C/L WB/WOT OEM ECUs... There have been a couple of stories of Fel-pro users having just that problem...I think I'd use the w/b to set my WOT fuel map, then run it from the tables most of the time. That's what several FelPro users I know do. Kendall Frederick > -----Original Message----- > From: owner-diy_efi@xxx.org]On > > Thoroughly appreciating this thread everyone but here's a > Newbie's question... > > Is WB O2 closed loop control at WOT actually safe? > > I was just thinking that any fouling and/or other malfunction of > the O2 sensor > etc could result in you going way lean under load with > catastrophic results... > > I'm thinking that you would need to have a "WOT Limp To The > Finish Line" mode > so perhaps you shouldn't disable the open loop stuff...rather have it take > over if WB O2 output falls out of a pre-determined range for WOT > or something > like that... > > What say you knowledgeable folks? > - ---------------------------------------------------------------------------- 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, 8 Apr 2000 23:39:09 -0400 From: "nacelp" Subject: Re: C/L WB/WOT OEM ECUs... Like anything electricailly "smart" you MUST remain in control. That is be aware of your monitoring. No one item, in your tool box is the end all of engine mangement, or diagnostics. If some thing is going wrong, very *rarely* is it an *instantaneous* failure. If the sensor is starting to fail, least every O2 I've ever seen, gives you some warning. YES, level of tune will shorten that warning time at WOT. That's why a driver has to be on his toes. Kinda brings a new level of cheating to the forfront also. ie I can kill an O2 sensor, hood closed and from several feet away, if the engine is running. Like I have been harping about for almost two years now, use your bargraph O2v monitors as an ****indicator***. Use LEDs to give you a rough estimate of what is going one. Have a EGT or some second monitor. If you can't watch an EGT and LED monitor, to prevent a misQ'd O2 well, then there are other problems (no flame meant), just stating that you have to be in aware of your environment, and in charge... The Limp Home Devise is preventing the problem, ie the driver. Yes, you can set up a DC monitor and see if it's is abnormally short, but then to be accurate that needs redundant. So where do you stop, for ever one fault you can find another, and probalby cone up with 4-6 failure modes, and by the time you have redunancy for all of them you have really gotten away from simplicity is the key to design. Grumpy > There have been a couple of stories of Fel-pro users having just that > problem...I think I'd use the w/b to set my WOT fuel map, then run it from > the tables most of the time. That's what several FelPro users I know do. > Kendall Frederick > > Thoroughly appreciating this thread everyone but here's a > > Newbie's question... > > Is WB O2 closed loop control at WOT actually safe? > > I was just thinking that any fouling and/or other malfunction of > > the O2 sensor > > etc could result in you going way lean under load with > > catastrophic results... > > I'm thinking that you would need to have a "WOT Limp To The > > Finish Line" mode > > so perhaps you shouldn't disable the open loop stuff...rather have it take > > over if WB O2 output falls out of a pre-determined range for WOT > > or something > > like that... > > What say you knowledgeable folks? - ---------------------------------------------------------------------------- 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: Sun, 9 Apr 2000 01:08:26 -0400 From: "nacelp" Subject: Re: GM ECU for Turbo Motorcycle? Just 11K. In the v-8 world that 5,500 rpm. Would be work yes, for further info.: www.syty.org maybe .com, .net or somethng like that Look up "the ecmguy" www.tunercat.com write TerryK@xxx.net Last two offer editing software, ya got to check on what's currently available. John G (list owner) had publiched info on his 2 bar 730 here. So now ya got some homework Grumpy > I'm building Kawasaki ZX-11 motorcycle with a Aerocharger turbo, max engine > RPM is 11,000. Is there a GM ECU that I could adapt to this project? > > cheers > Steve L. > > > ______________________________________________________ > 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 > - ---------------------------------------------------------------------------- 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, 08 Apr 2000 22:40:18 -0700 From: garwillis@xxx.com (Garfield Willis) Subject: Re: C/L WB/WOT OEM ECUs... On Sat, 08 Apr 2000 18:28:45 -0700, Doug Dayson wrote: >Is WB O2 closed loop control at WOT actually safe? > >I was just thinking that any fouling and/or other malfunction of the O2 sensor >etc could result in you going way lean under load with catastrophic results... then On Sat, 8 Apr 2000 21:50:54 -0400, "Kendall Frederick" wrote: >There have been a couple of stories of Fel-pro users having just that >problem...I think I'd use the w/b to set my WOT fuel map, then run it from >the tables most of the time. That's what several FelPro users I know do. Yup, in the face of additional failure modes (more electrics), you might very well decide that O/L is a more conservative/safer approach. The problem has often been that in an atttempt to get those O/L tables just right, sometimes you err on the lean side, with disasterous results too. Hence the interest in using C/L WB sensing to prevent that from happening. That risk has to be weighted against the likelyhood of sensor/electrics failure, for sure. But everyone's assuming that the major role of precision O2 sensing WILL be in the tuning/cal work that's needed for dialing in better O/L maps. This thread is just for those intrepid souls who insist on going one step further and pushing the envelop of C/L control. Using this sensing technology to cheaply open that up to some who want to experiment, is kinda like a "second-order effect". Not the main thrust of the technology, but an interesting and alluring one. So don't misunderstand the motivation; nobody is thinking (I hope) that C/L WOT control is always safer than O/L. You're trading the possibility of more *precise* mixture control, for the perhaps increased possibility of failure in the system, especially in it's infancy. This is often the case; I'm sure FelPro has heard from it's share of clients who blew engines, and blamed it on the C/L controller, rightly or wrongly. Realistically, a failsafe/fallback mode "if the WB O2 sensor suffers sudden catastrophic failure during WOT" is probably dreaming. Where it really matters, you likely just don't have time to decide, "oh, the O2 sensor isn't responding, let's transition to O/L". We're talkin fractions of a second. Altho the OEM ECUs do have just that sort of fallback, I really wonder if it's capable of responding fast enough, should you be under *heavy* load and suffer a lean transient due to sensor failure. OTOH, certainly wise to consider such "what-ifs", and decide if there's anything that can be done to mitigate. I'd say it's a sage and appropriate observation to bring up at this point. There be some wee dragons here. :) 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: Sun, 9 Apr 100 19:54:33 +0800 (WST) From: Bernd Felsche Subject: Re: C/L WB/WOT OEM ECUs... Garfield Willis writes: >Now you're starting to put nearly as much smarts in that lil goiter >that's fooling with the simulated stoich point, as you have in the OEM >controller. So you're approaching the point at which you might as well >just bite the bullet and create a custom controller, and dump the OEM >brain-stem? Well, maybe not quite, but you getmedrift. Depends on how >much you wanna play with the electrics. That is the situation as I saw it. One "advantage" is that you don't have to have intimate knowledge on how to drive the output signals; but you will probably have to deal with a number of inputs (other than O2) and massage them before delivering them to the OEM ECU. At least on the fueling side. The other advantage is that you only have to deal with the AFR in a fairly lazy manner; i.e. there are no critical timing functions related to the O2 sensor response. Of course; you may have to deal with some of the outputs as well; e.g. when the duty cycle is limited by the OEM tables and "safety values". Of course, I could be being pessimistic about it all... - -- 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: Sun, 09 Apr 2000 04:41:50 -0700 From: Carl Summers Subject: RE: C/L WB/WOT OEM ECUs... Hi Gar, I have done alot of tip in AE with screw type superchargers and GM computers and there are quite a few variables in the GM software that affect this....I am trying to answer this as best I can up front but as we all know...more questions begat better answers....I know about the TPS delta enrich....I know about the delta MAP enrich....I know about the multiplier for both.....and I know about the time constant delay for all of the above.....the suck part about making all these work together is lots of time.......and from what I have spent the most time with in a PCM...the time constant(while in GM closed loop) can only be bypassed for a max of a little over 2 seconds......I love what we are talking about for UEGO closed loop control, but can't see it happening without rewriting the code(what I change above is lookup tables :<) for those of us still learning :).....Walter.....any ideas??? - -Carl Summers - -----Original Message----- From: owner-diy_efi@xxx.org]On Behalf Of Garfield Willis Sent: Friday, April 07, 2000 9:48 AM To: diy_efi@xxx.org Subject: Re: C/L WB/WOT OEM ECUs... On Fri, 7 Apr 2000 12:59:32 +0100, "Rich M" wrote: >Assuming my understanding is correct, accel. enrichment and the like is >performed in response to rate-of-change signals, notably from TPS. This can >still be accomodated while limiting the actual max. TPS value as has been >already suggested. This would allow the ECM to perform transient (required) >enrichment, whilst inhibiting steady-state O/L operation. If the accel. >enrichment is also a result of rate-of-change of MAF also, then this might >not be so easy? As mentioned earlier, at least some aftermarket controllers (maybe all?) have tables to apply enrichment for ALL/any of the below: (1) throttle rateOchange (2) throttle pos (the actual position itself) (3) MAP rateOchange These of course are applied on top of the base fueling tables, if I understand the proper nomenclature. BUT, the issue of control over O/L vrs C/L has more to do with what events/limits THROW you into the use of these tables. To illustrate what I'm getting at with that last sentence, consider that altho say for example #3 is USED in determining how much enrichment to add once in O/L, it may not of itself cause you to be thrown into O/L. So the key variables we need to be able to control in order to keep OUT of O/L are the parameters that cause us to be thrown into O/L in the first place. Obviously, throttle pos and rateOchange have limits that throw us into O/L, and we may indeed be able to fudge these since they aren't usually part of/parameters of the base fueling tables. But the problem comes in when an engine parameter is used both to trigger O/L and is used in fueling calcs. Hence, trying to intercept and munge MAP values, for example, isn't gonna be workable, unless we have some way of controlling the *limits* themselves that cause transition to O/L. In general, that's why control over the limits that force O/L seems to always be a better plan than interception and munging of sensor inputs. The question remains, do we have enough authority via table values and flags, to control/prevent transition to O/L if we/when we want to. In addition to the OEM controllers, someone who's an active part of the 332 group and is familiar with it's code, could perhaps say what the O/L trigger conditions/parameter limits are, and if even that controller could be "persuaded" to stay in C/L via cal changes alone. That might be a good examplar place to begin, since all the code is visible. Anyone familiar with that code? Obviously if you have full access and control over the code, you can do better than just faking out the ECU like we've been discussing, so I'm not proposing the above as the desired way of doing C/L WB in something like the 332; just that since it's code is available and open, it might still be an instructive example to look at. Pretend it's an OEM controller you can peer into openly, but can't change the coding, and then see if you can get by with just cal changes. 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 - ---------------------------------------------------------------------------- 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 #141 ***************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace "diy_efi-digest" in the command above with "diy_efi".