DIY_EFI Digest Saturday, 10 February 1996 Volume 01 : Number 038 In this issue: Re: Sequential Setup? Fuel Injector Valve Phasing... Re: Multiprocessor system Re: Sequential Setup? Re: Multiprocessor system Re: EFI vs. Carb Re: Multiprocessor system - Who uses intel ups Re: Fuel Injector Valve Phasing... Re: Electronics suppliers Re: Multiprocessor system Re: Electronics suppliers Re: Multiprocessor system Re: Fuel Injector Valve Phasing... Re: Multiprocessor system Re: Electronics suppliers Re: Electronics suppliers Re: Fuel Injector Valve Phasing... Re: Fuel Injector Valve Phasing... Re: Electronics suppliers RE: Electronics suppliers Re: Sequential Setup? Re: Sequential Setup? [none] format Re: Electronics suppliers Re: Fuel Injector Valve Phasing... Injector Phasing... format Re: Electronics suppliers Re: Injector Phasing... Re: Multiprocessor system Re: Multiprocessor system See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: atsakiri@xxx.com Date: Fri, 09 Feb 96 08:46:36 -0500 Subject: Re: Sequential Setup? > The economy was another matter altogether. By timing the injection so that > there is the minimum time for the fuel/air mixture to sit in the inlet you > got the most economy. This is because the droplets coalesce and form larger > droplets, which take longer to burn. Hence you need more of them to get all > of the air used and thus economy suffers. I was given the parallel of the > droplets being like onions, you need to burn off each layer until they are > all gone, the bigger the droplet the more layers. Will injecting fuel onto a closed, warm intake valve provide any benefit, by increasing the vaporization of the fuel? Instead of coalescing, might the fuel droplets evaporate better? Anthony Tsakiris - --------------------------------------------------------------------------- The opinions expressed are my own and not necessarily those of my employer. ------------------------------ From: Timothy Coste Date: Fri, 9 Feb 1996 09:00:11 -0500 Subject: Fuel Injector Valve Phasing... I just had to jump in on this one, since my research is mainly focussed on this aspect of fuel injection... The best time to fire an injector relative to the intake valve event is engine/injector dependent. At part throttle of course. As mentioned, at/near WOT, injector duty cycle is so high, it hardly matters when the injector fires. At light throttle, my understanding of industry (US industry at least) is that the common goal is to spray the fuel directly on the (closed) intake valve. The idea is that the hot valve will vaporize the fuel while waiting for the valve to open. Then, with pure vapor, the whole onion peeling (a good analogy) idea is not needed. Gasoline engines don't like burning droplets, especially large ones. Diesels on the other hand... Anyway, assuming you can target the injector accurately on the valve, and that the valve is hot, and the injector spray is only of average quality...hot valve evaporation seems to be best. Now, if you can't get to the valve, or possibly (some of my research) your injector droplets are fine enough already, then it's best to spray so that air flow is high (to keep droplets off the walls and coalescing) and port residence is minimized. This ensures, as Peter mentioned, that the "onion" is as small as possible. Anyway, those are some of the principles and, as usual, you can't generalize for all engines. To put this in to perspective, if you aren't a major auto manufacturer meeting government regs, fire the dang thing whenever you prefer. It's not THAT big a deal. Now, lean transients on acceleration...there's one you should compensate for... Tim Coste tlcoste@xxx.edu ------------------------------ From: Land Shark Date: Fri, 9 Feb 1996 08:31:09 -0700 (MST) Subject: Re: Multiprocessor system At 01:05 AM 2/9/96 -0800, you wrote: >question : who uses intel ups in automotive or engine control >applications. Answer: Ford: 8061 (a custom variant of the 8096) Bosch, 8051, 8052, 80515 (Siemens) and 80196 .. some boxes with both a '51 and '96 Siemens, using their 80C166 and C167 variants of the intel core (and others I'm sure) Jim ------------------------------ From: ehernan3@xxx.com (Edward Hernandez (R)) Date: Fri, 9 Feb 1996 10:25:51 +0500 Subject: Re: Sequential Setup? "For sequential injection, most common method, is to time the injector to CLOSE with the closing of the intake valve." No, the most common method, among OEMS, is to inject while the valve is closed. The onion analogy mentioned in a later post is a good one once you get fuel into the chamber, but injecting onto a hot inlet valve vaporizes a majority(not all) of the fuel before it gets into the chamber. Also, some fuel which has piled up on the valve without vaporizing gets sheared as it is dragged past the valve and seat, reducing droplet size significantly. As good as injectors have become, they still inject droplets, not vapor. Injecting past an open valve will introduce these droplets into the chamber untouched, which, as the onion analogy correctly describes, take longer to burn. Furthermore, there is risk of washing the oil coating off of the chamber walls during open valve injection, which puts engine durability(rings, pistons, bore finish) at risk. "correct me if I'm wrong. when you go from hi vac to WOT, the only air to enter the cylinders is previously measured air between the throttle and the MAF and air passing through the MAF. So the only error would be in not measuring that volume between T-body and MAF. Unless the distance is large I don't see it as a problem." You are correct, except that the volume between the throttle body and the MAF is usually large enough to be a problem. Usually, that is. Some applications are better then others when it comes to this phenomenon. ------------------------------ From: atsakiri@xxx.com Date: Fri, 09 Feb 96 10:47:33 -0500 Subject: Re: Multiprocessor system > question : who uses intel ups in automotive or engine control > applications. "ups?" If you mean CPUs, it's public knowledge that Ford uses Intel chips. Anthony Tsakiris - --------------------------------------------------------------------------- The opinions expressed are my own and not necessarily those of my employer. ------------------------------ From: MSargent@xxx. Sargent) Date: Fri, 9 Feb 1996 10:43:38 -0500 Subject: Re: EFI vs. Carb > Car Craft did an EFI vs. carb engine. They were about equal in running (hp & > torque) ... Hot Boat magazine built up a 502CI marine engine and dyno tuned it with a Holley on top. Then they removed the carb and intake and bolted on a Cutler FI system, and immediately picked up another 25 HP. And we all know that the EFI engine will start and idle much better than a carb engine. +--------------------------------------------------------------------------+ | Michael F. Sargent | Net: msargent@xxx.com | Phone: 1(613)721-0902 | | Gallium Software Inc.| | FAX: 1(613)721-1278 | +--------------------------------------------------------------------------+ ------------------------------ From: mpm@xxx.com (Martin Mayhead) Date: Fri, 9 Feb 96 15:30:39 GMT Subject: Re: Multiprocessor system - Who uses intel ups Advanced Automotive Electronics Ltd in the UK make a range of ignition and fuel injection/engine management boxes for the aftermarket/club racer based on the Intel 80C196KC running at 16 & 20 Mhz. This chip is a commercial development of the 8061 (or is it 8065) developed for Ford and used in their EEC and EDIS modules. The 80196 at 20Mhz is an approx. 4 mips processor with onboard A/D, timers and event capture/scheduling hardware. If your question was aimed at discovering the pitfalls and/or advantages of Intel uC's (in particular the 80196) I would be happy to discuss this further - it is actually very straightforward to use and well documented by Intel (yes that surprised me too). Regards, Martin Mayhead (mpm@xxx.com) ------------------------------ From: Fred Miranda Date: Fri, 9 Feb 1996 08:18:55 GMT Subject: Re: Fuel Injector Valve Phasing... >Now, >if you can't get to the valve, or possibly (some of my research) >your injector droplets are fine enough already, then it's best to >spray so that air flow is high (to keep droplets off the walls >and coalescing) and port residence is minimized. Tim, For those of us who can't hit the valve or have none, any tips on injector or anything else that would promote a fine spray? As for WOT duty cycles, you can't assume they are high. An engine with a torque peak at 5krpm and 80% duty cycle will have a duty cycle something less than 40% at 2.5krpm. Obviously haphazard injection timing could hurt you here, esp if you can't hit the valve. Fred ------------------------------ From: John T Stein Date: Fri, 9 Feb 1996 11:50:45 ET Subject: Re: Electronics suppliers > Date: Thu, 08 Feb 1996 22:19:08 +0000 (GMT) > From: Jim Staff > Subject: Electronics suppliers > To: diy_efi@xxx.edu > Reply-to: diy_efi@xxx.edu > What are good places to get electronics stuff? Could you provide me with > the names, number, and costs of catalogs plus you personal thoughts on them. > > I know about digi-key : I've had good experiences with them. But they are a > little expensive and don't carry a few things I like (Such as mos-fets and > bipolar transistors) Also the have some strange love of national semiconductor. > Which is a good company and provides good parts. > Archer [Radio shack] : They've got thier good and bad points. > They are a tad bit more expensive. And the selection is limited. But after all > they are just a few blocks away [1 mile in my case] so you have instant > satisfaction. Also they have a knack to have the IC's I need but never the > resistors or capacitors I need. They have more diodes than I've ever seen and > have never heard of some of the ones they have. > > If anyone know about a company called ____***ARROW***____ please give me > information. They are a good supplier and carry buttloads of stuff. > > Bye, > Jim Staff > Jim, Arrow is an industrial supplier, like Pioneer, Schweber, et al. These folks sell primarily to established, commercial accounts and usually do not court the "hobby" trade. They usually have significant minimum order $ policies. IMO you will not do too much better than DigiKey, all things considered. John ------------------------------ From: dn Date: Fri, 9 Feb 96 10:22:54 MDT Subject: Re: Multiprocessor system Clint Corbin wrote: > I have been thinking about a fuel injection system composed of four 68HC11 > microprocessors. The first processor would run the ignition system. It I am working (slowly) on an idea like this, but not quite so ambitious, I think 4 processors is a little overkill. My system will use 2 for now, one for ignition and one for fuel. I know some guys who did a natural gas injection system using 4 processors, but only 2 actually ran the engine, the other 2 were strictly for data aquisition and communications for developement purposes only. > There would be two seperate (and identical) fuel injection systems. Each > would control 4 fuel injectors. For a 12 cylinder engine, one more fuel > injection subsystem could be added without change to the master controller. Por Que? You could just add more injector drivers, unless you want full sequential. Seems to me the software would be a nightmare for this kind of system. > Another advantage is that you could build and test the ignition system before > you had to make the rest of the system. This would at least let you know This is exactly what I had in mind, and after I get it running with the basic system, move on to DIS... > One question I do have how should I buffer the various signals that need to > go to multiple modules? Would I have to? Would the standard input filtering > be enough of a buffer to feed up to 4 inputs simultainiously? I would love Motorola was good enough to include the SPI interface port on the 'HC11. This thing is extremely useful, essentially a synchronous serial port running at 1Mbit/s! It can be set up as a master or slave, requires only 2 wires to transmit data, and you can hang as many devices as you have chip select lines for on the bus. You could use a low impedence wire-AND type of scheme where the comm lines are just pulled up to VCC, and each device has an open collector transistor to pull the line low. Noise is basically impossible on this type of system. Also, the SPI is extremely easy to use, you just store a byte into a register and it sends it out serially while receiving a byte from the slave at the same time. As far as the code goes, you could use the 'HC11E2 which has 2k of EEPROM instead of EPROM. This should be plenty of code space, since you're splitting up the operating system into several parts anyway. You can put a header on the circuit board, tied to the RS232 port on the 'HC11, and reprogram the EEPROM any time with a laptop. Don't even have to pull the chip to erase or reprogram it. Regards dn - -- - --------------------------------------------------------------------- Darrell A. Norquay Internet: dn@xxx.ca Datalog Technology Inc. Bang: calgary!debug!dlogtech!darrell Calgary, Alberta, Canada Voice: +1 (403) 243-2220 Fax: +1 (403) 243-2872 @ + < __/ "Absolutum Obsoletum" - If it works, it's obsolete -------------------------------------------------------------------- ------------------------------ From: "George M. Dailey" Date: Fri, 9 Feb 1996 11:46:29 -0600 Subject: Re: Electronics suppliers At 11:51 PM 2/8/96 -0600, Thomas Sparks wrote: > >Thomas Registry is online at: >http://www.thomasregister.com:8000/finder/gate1.html Is there a "new user" pass word and login id? Tried and failed. GMD > ------------------------------ From: "George M. Dailey" Date: Fri, 9 Feb 1996 12:00:43 -0600 Subject: Re: Multiprocessor system At 11:42 PM 2/8/96 PST, Clint wrote: >I have been thinking about a fuel injection system composed of four 68HC11 >microprocessors. Clint, I bet you play doom on the nightmare setting :{} What do you plan to gain by using 4 microprocessors? good luck fella, GMD ------------------------------ From: Timothy Coste Date: Fri, 9 Feb 1996 13:35:31 -0500 Subject: Re: Fuel Injector Valve Phasing... To Fred's question about improving spray... All I can say is that we use specially prepared injectors. Pneumatic assist injectors have been around for a long time. From what I've seen so far however, their spray angles are too huge even given the very small (< 10 micron) droplets. Maybe if you were certain air flow was high during injection, they could work. Easy concept and assembly, but you need pressurized air. We also work with some proprietary injectors here which are still undergoing development. These produce relatively fine (about 30 micron I believe) sprays in excelently controlable patterns. I read (in SAE?) that Ford is building a new injector facility...maybe they have something cool about to go into production??? Other than that... I believe I've seen very high pressures (which I guess would require shorter duty cycle times) causing more turbulence at the nozzle and therefore better atomization. This is something one could tinker with at the home level. I don't know for sure the effect of boosting pressure on angles though. I think that next time I run my test engine (a SEFI 4 cylinder) maybe I'll try fine spray injectors and switch the leads between injectors to get them to fire on an open rather than closed valve. Hmmmm, what was that firing order... As to real duty cycles... I guess I didn't consider full load-lower speed. I'm not really sure what they are (duty cycle that is) at those conditions. I baby my engine (head is swiss-cheesed with sensors) and rarely see over half of max torque. If the thing grenades now...no Ph.D.! :( In general, I've seen increased load- speed reduces the effects of fuel prep. Engines hotter, more turbulence, etc. so I still think it's less important as power output increases. I'll stop rambling now...need to actually get some work done. BTW...sorry, but our Unix mail program has no spell checker...try editing your already typed mail in vi! Tim Coste tlcoste@xxx.edu ------------------------------ From: pjwales@xxx.net (Peter Wales) Date: Fri, 09 Feb 1996 14:56:45 -0500 Subject: Re: Multiprocessor system >I have been thinking about a fuel injection system composed of four 68HC11 >microprocessors. By heck lad, you really know how to do things the hard way don't you. I'm sure 1 68HC11 will handle it Peter Wales President Superchips Inc Chairman Superchips Ltd "Timing is everything" Superchips home page with all the answers http://www.superchips.com ------------------------------ From: Doug Rorem Date: Fri, 9 Feb 1996 13:45:29 -0600 Subject: Re: Electronics suppliers >> >>Thomas Registry is online at: >>http://www.thomasregister.com:8000/finder/gate1.html > >Is there a "new user" pass word and login id? > >Tried and failed. >GMD George, Try http://www.thomasregister.com:8000/adfinder.html That page has a register option for new users. - -- Doug Rorem University of Illinois at Chicago (312)-996-5439 [voice] EECS Department RM 1120 (312)-413-1065 [fax] 851 S. Morgan Street (708)-996-2226 [pager] Chicago, IL 60607-7053 rorem@xxx.edu ------------------------------ From: Land Shark Date: Fri, 9 Feb 1996 13:11:46 -0700 (MST) Subject: Re: Electronics suppliers At 11:46 AM 2/9/96 -0600, you wrote: >>Thomas Registry is online at: >>http://www.thomasregister.com:8000/finder/gate1.html > >Is there a "new user" pass word and login id? No, you just need to register .. start at the top of the site and register (start at the top by eliminateing the URL after the 8000!) Jim ------------------------------ From: Gerald Luiz Date: Fri, 9 Feb 96 12:18:04 PST Subject: Re: Fuel Injector Valve Phasing... Hi everyone. I am pretty new to the list so I have just been following along to see what is going on. This last thread has been interesting about the droplet size. There is that company (in Australia I think) that makes the injector that is pressurized with air, supposedly to get a smaller droplet size. Does anyone have any experience/comments about it? Gerald Luiz gluiz@xxx.com ------------------------------ From: ehernan3@xxx.com (Edward Hernandez (R)) Date: Fri, 9 Feb 1996 15:57:03 +0500 Subject: Re: Fuel Injector Valve Phasing... "I read (in SAE?) that Ford is building a new injector facility...maybe they have something cool about to go into production???" Maybe ;) BTW, there is another source of pressurized air available "for free" on any engine. You just have to remember that by "pressurized" you mean that a pressure differential exists. Toyota do this already, ------------------------------ From: mecheng9312@xxx.CA Date: Fri, 09 Feb 1996 13:07:14 -0700 (PDT) Subject: Re: Electronics suppliers On Fri, 9 Feb 1996, George M. Dailey wrote: > At 11:51 PM 2/8/96 -0600, Thomas Sparks wrote: > > > >Thomas Registry is online at: > >http://www.thomasregister.com:8000/finder/gate1.html > > Is there a "new user" pass word and login id? > > Tried and failed. > GMD > > > There should be a set-up of new account or something of the like in the Web site. It's been a while since I used the Thomas Registry and I remember when I tried it the first time I had problems. Input the information it asks for and a new account/username will automatically be set up for you to use anytime. Make sure all lines are filled out in the application or else I think you'll have problems getting in. Later, Jason A. White. > ------------------------------ From: Jeff Hansen <103600.3364@xxx.com> Date: 09 Feb 96 16:20:05 EST Subject: RE: Electronics suppliers > What are good places to get electronics stuff? Could you provide me with > the names, number, and costs of catalogs plus you personal thoughts on them. Mouser Electronics is a good source for electronic parts. It is very much like Digi-Key. Home Page: http://www.mouser.com Sales and Service Phone Number: 1-800-346-6873 E-mail orders: sales@xxx.com No minimum order for USA, Canada, Mexico. Later - Jeff Hansen ------------------------------ From: sian@xxx.uk (RAGHBIR SIAN) Date: Fri, 9 Feb 1996 18:59:18 GMT Subject: Re: Sequential Setup? >At 03:40 PM 2/8/96 CST, Tom wrote: > >>At idle and partial throttle is where you would expect the >>largest gains in performanace/economy. I have heard figures >>ranging from 2% to 10% improvements by properly timing >>the injection on sequential injections. > At 21:58 -0500 08/02/96, Peter Wales wrote: >We did a lot of tests on the dyno on exactly this and found NO improvement >in power. The reason is simple, you need air, and fuel to burn in it, and if >you have the right amounts of each you will get the most power. > >The economy was another matter altogether. By timing the injection so that >there is the minimum time for the fuel/air mixture to sit in the inlet you >got the most economy. This is because the droplets coalesce and form larger >droplets, which take longer to burn. Hence you need more of them to get all >of the air used and thus economy suffers. I was given the parallel of the >droplets being like onions, you need to burn off each layer until they are >all gone, the bigger the droplet the more layers. > > >>For sequential injection, most common method, is to time >>the injector to CLOSE with the closing of the intake >>valve. > >Exactly > Peter may i ask you how this particular research was carried out (i mean on an Engine dyno or Chassis dyno)? The reason i ask this is because you CANNOT quantify any results without looking into mixture preparation, temperature's of the inlet valve, fuel, inlet manifold wall, port velocity and also the differential of pressures in the inlet ports, Combustion chamber and the exhaust ports, preparation of air prior to fuel injection, fuel droplet size.............. also how the engine air is polled (Queing)........ i could carry on but have decided to stop. You said that there were No improvements in power Well i must say different. I carried out some (well alot of) research on this subject from a combustion point of view. I saw a reduction in harshness (uneven combustion) and INCREASE in Power (Torque) when you FINISHED or JUST FINISH injecting the fuel just before the inlet valve started to open. I am also assuming that you did your tests at a steady state. Test done in steady state only sometimes give you an increase, but mostly show NO increase in power. The only way to see the effects of the above is to be in constant TRANSIENTS which is were our engines spend 80% of their time. I cannot say alot more than this as i am contractually bound but if you would like me to expand on this then i will certainly try my best within my constraints. The other thing that really gets up my nose is when people say that they have an increase in power but no increase in torque. These two items are interelated. I do beg your pardon for any spelling or typing errors made. Regards R.S.Sian >>>>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<< Raghbir Sian Engine Control and Combustion Analyst "As Always A ***CONTROL*** Freak" A committee is a group of the unwilling, chosen from the unfit, to do the unnecessary.... Anonymous Life is just one damned thing after another... Joseph Heller Time spent on any item of the agenda will be in inverse proportion to the sum involved. E-mail: sian@xxx.uk >>>>>>>>>>>>>>>>>>>>>>>>>>><<<<<<<<<<<<<<<<<<<<<<<<<<<<< ------------------------------ From: pjwales@xxx.net (Peter Wales) Date: Fri, 09 Feb 1996 18:56:03 -0500 Subject: Re: Sequential Setup? The tests were run on an engine dyno. The procedure was to run the test at a given rpm, measure the power and then change from batch to sequential injection. In each case the fuelling was optimised for peak power at that RPM. It made no difference. However, the fuelling requirements, if different, always gave better economy on sequential injection. We were only looking for power. >The reason i ask this is because you CANNOT quantify any results without >looking into mixture preparation, temperature's of the inlet valve, fuel snip I didn't quantify them, I simply said that you didn't get more power. I wasn't really looking for economy, but being an inquisitive sort of character (some people call me nosey) I wanted to find out what and why, so I tried it and the results were not defineable enough. This is because all testing was carried out at WOT and on the dyno we used, part throttle positioning was not sufficiently repeatable so we didn't use it. >Well i must say different. >I carried out some (well alot of) research on this subject from a combustion >point of view. I saw a reduction in harshness (uneven combustion) and >INCREASE in Power (Torque) when you FINISHED or JUST FINISH injecting the >fuel just before the inlet valve started to open. I didn't alter the injection timing, just the mode. > >I am also assuming that you did your tests at a steady state. Test done in >steady state only sometimes give you an increase, but mostly show NO >increase in power. Thats what I found > >The only way to see the effects of the above is to be in constant TRANSIENTS >which is were our engines spend 80% of their time. Now I'm getting confused. Why try and define economy for a transient which is not defined. On that dyno, we couldn't have reproduced a transient, never mind measured the power developed during it. How do you define power during a transient? HP is a function of torque and RPM and if the RPM is changing what does the answer mean? Despite your willingness to disagree with me Sian, I don't think we do. You are measuring under one set of parameters and I under another. I still say that it doesn't matter whether you use sequential of batch injection, the power won't change. I'm talking about *power* ie 300HP at 6000RPM on WOT, not what happens at 1800 RPM on 1/4 throttle. That ain't power, thats pussy footing :) Peter Wales President Superchips Inc Chairman Superchips Ltd "Timing is everything" Superchips home page with all the answers http://www.superchips.com ------------------------------ From: john a carroll Date: Fri, 9 Feb 1996 20:08:30 -0700 Subject: [none] ------------------------------ From: jac@xxx.us (john carroll) Date: Fri, 9 Feb 96 20:57:00 PST Subject: format This suggestion could set off a firestorm. God help me if I should misspell a word. After a thread has run for a few exchanges, one has good recall of the original thought. I suggest that text be added at the TOP of responses to allow one to skip rereading all that went befor. ------------------------------ From: "Mark Hillier" Date: Fri, 9 Feb 1996 23:26:02 +0000 Subject: Re: Electronics suppliers > >I could go on with more, but you're better off to do a little research > >on your own. I'm up in Canada, so I don't have American addresses > >and phone numbers for most of these places, but you can look them up > >in the Thomas Registry at your local library. Another good source... > > Thomas Registry is online at: > http://www.thomasregister.com:8000/finder/gate1.html > > VERY handy. > And *very* password protected. If it is anything like the printed version you have to have some very deep pockets to afford this kind of things. Practically speaking, you have to be buying *lots* of stuff ALL the time for something like the Thomas Registry to be worth it (IMHO) Mark Hillier HVW Technologies ------------------------------ From: Fred Miranda Date: Fri, 9 Feb 1996 20:58:17 GMT Subject: Re: Fuel Injector Valve Phasing... >BTW, there is another source of pressurized air available "for free" > on any engine. You just have to remember that by "pressurized" you > mean that a pressure differential exists. Toyota do this already, this reminds me, Mazda uses this in their rotarys. there is a small port located just below the injector nozzle which leads to a port upstream of the throttle. this introduces air to the fuel in a small chamber befor it reaches the port runner, at which point it hits a perforated disk in the air stream that further atomizes the fuel. Fred ------------------------------ From: Timothy Coste Date: Sat, 10 Feb 1996 00:07:03 -0500 Subject: Injector Phasing... Boy, I really hate (I think) to get into this one but... I believe Peter and Sian are saying the same thing, but from totally different perspectives. Peter is concerned with WOT...Sian is (I think, since hie research sounds similar to mine) concerned with day-to-day driveability. There's no way you can meet emissions regulations and customer (i.e.- consumer) satisfaction without being extremely concerned with transients, not to mention cold-start/ warm-up strategy. Increasing cycle-to-cycle variability, increasing efficiency at part-throttle, etc. (COVimep, transient response, etc) are all concerns of manufacturers, not tuners/racers. Show me a racer who minds a miniscule off-idle stutter versus 20hp and a 1000ppm increase in HC and I'll show you a big three engineer riding with a racing team. :) If you care about cyclic variability and such, WOT is something you'll cherish until Big Brother (or the Euro equivalent) mandates WOT testing (coming to a theater near you). For USA readers, be VERY happy uncle sam (no Caps for modern gov't) lets WOT go for now! I'll stop discussing this unless there is a reply directly to my comments since this is getting way off of the diy category. If you care enough about COVimep, transients, and cold starts, you're working for an auto manufacturer and not in your garage. Or your WAY too optimistic about your 4 micro-processor's having nothing to do during idle times. :) Sorry, I really enjoy my own humor late at night too much. Glossary of Terms COVimep - coefficent of variation of indicated mean effective pressure...a measure of cyclic variability in an engine. ppm -parts per million HC -hydrocarbon (fuel) emissions WOT -wide open throttle Big Brother-governments everywhere Euro -European, from the new-world point of view -I could go on, but I've worn out my own funny bone. I'm killing myself. If you want more, you're in worse shape than I. Tim Coste tlcoste@xxx.edu ------------------------------ From: Timothy Coste Date: Sat, 10 Feb 1996 00:19:07 -0500 Subject: format Personally, I prefer that, if you feel you have to quote earlier messages, you add your text at the end. That seems to be the norm, as you are _adding_ (I hope) to a previous discussion. Text in the front gets lost to me until I go to the end of a message, see no addition, and then back-track to the beginning to pick out whether the specific editor adds <, or : or ? to a quoted message. Ah, do you think my ? is an addition or a question? (answer-it's a question.) IMHO, people will reply however they want dependent upon their mood, editor, etc. All I know is, vi sucks. Reply however it's easiest...if yo have something useful to say, I'll figure it out (spelling errors or not). Tim Coste tlcoste@xxx.edu Glossary (I forgot) IMHO - In my humble opinion vi - Visual editor...UNIX left-over that my mailer uses yo - A spelling error I caught after the fact...means "you" ------------------------------ From: Johnny Date: Fri, 09 Feb 1996 21:45:48 -0800 Subject: Re: Electronics suppliers Mark Hillier wrote: > > > >I could go on with more, but you're better off to do a little research > > >on your own. I'm up in Canada, so I don't have American addresses > > >and phone numbers for most of these places, but you can look them up > > >in the Thomas Registry at your local library. Another good source... > > > > Thomas Registry is online at: > > http://www.thomasregister.com:8000/finder/gate1.html > > > > VERY handy. > > > And *very* password protected. If it is anything like the printed > version you have to have some very deep pockets to afford this kind > of things. Practically speaking, you have to be buying *lots* of > stuff ALL the time for something like the Thomas Registry to be worth > it (IMHO) Mark, it is free if you just register. Hit the root link first: http://www.thomasregister.com:8000/ Then you will get a password. Keep in mind that this is a limited edition of there complete listing that is available on CD-Rom... but still has a ton of listings. - -j- ps: alll of thise nonsinse aboot mispeeling ands tipografical erroers is sownding veery winy. It cood bee alott woorss. ------------------------------ From: Carter Hendricks Date: Fri, 9 Feb 1996 21:48:21 -0800 (PST) Subject: Re: Injector Phasing... Wow. This came up again. I promise this -weekend- to write up what I know about Alfa Romeo's sequential [and mechanical, and timing-adjustable fuel injection]. Event timing -can- make a difference. But for now one comment: On Sat, 10 Feb 1996, Timothy Coste wrote: > are all concerns of manufacturers, not tuners/racers. Show me a > racer who minds a miniscule off-idle stutter versus 20hp and a > 1000ppm increase in HC and I'll show you a big three engineer riding > with a racing team. :) Throttle control is a big issue with -fast- racers. I spent a little while with motorcycles. Power is very good. Falling is very bad. Smooth throttle response is superior to quite a bit of unruly power, at least when coming out of corners! The new telemetry I've seen published shows that throttle response is of key importance in automobile road racing, as well. I suspect that even [especially?] in drag racing throttle control is a key variable. No big deal, but the dichotomy in control system requirements may not be very substantial, may not be there at all. And lean is still mean. --Carter ------------------------------ From: "Clinton L. Corbin" Date: Fri, 9 Feb 96 22:55:20 PST Subject: Re: Multiprocessor system >Clint Corbin wrote: > >> I have been thinking about a fuel injection system composed of four 68HC11 >> microprocessors. The first processor would run the ignition system. It > >I am working (slowly) on an idea like this, but not quite so ambitious, >I think 4 processors is a little overkill. My system will use 2 for now, >one for ignition and one for fuel. I know some guys who did a natural >gas injection system using 4 processors, but only 2 actually ran the >engine, the other 2 were strictly for data aquisition and communications >for developement purposes only. > >> There would be two seperate (and identical) fuel injection systems. Each >> would control 4 fuel injectors. For a 12 cylinder engine, one more fuel >> injection subsystem could be added without change to the master controller. > >Por Que? You could just add more injector drivers, unless you want full >sequential. Seems to me the software would be a nightmare for this kind of >system. That's the crux of the matter. I want a fully sequential system. The 68HC11 does not have enough output compare ports to control 8 fuel injectors in a sequential system. The software for the main modules would be pretty basic. They would not have any of the advanced stuff in them, just the basics needed to properly run there system. They would be told how to MODIFY either the injector pulse or the ignition timing by the master controller. The system should be able to run without a problem without the master controller being connected at all. In fact, that is how I intend to build it: the ignition system, the fuel injection system, and finally, the master controller to impliment the more advanced features (such as ignition retard based on knock sensors). Because all of the modules are stand-alone, I do not need to use the serial interface to connect all of the modules. >As far as the code goes, you could use the 'HC11E2 which has 2k of EEPROM >instead of EPROM. This should be plenty of code space, since you're >splitting up the operating system into several parts anyway. You can put a >header on the circuit board, tied to the RS232 port on the 'HC11, and >reprogram the EEPROM any time with a laptop. Don't even have to pull >the chip to erase or reprogram it. Now this idea I like. I just do not want to get into the postion were I have to program the sub-modules through the master controller. This leads to a level of complexity I do not want to deal with. Yes, I know what most of you are thinking. And hey, you may be right. I cannot PROVE that I am sane. Can you? Basically, I am willing to put up with a bit more hardware complexity to get rid of software complexity. I find it easier to write code that runs the ignition, code that runs the fuel injectors, and code that runs the master, than to try to write one program that does everything. Not to mention most microcontrollers do not have enough hardware resourses (input captures, output compares, regular I/O ports, etc.) to run the system the way I want it to run. By breaking it up into modules, I have the hardware I need. And it makes the system extremly modular. Need a system for a V-16 (hey, you never know)? just use two ignition modules and four injection modules. One constant in each program would have to be changed. The master controller would not change at all. And do you think we could drop this spelling crap?!? That includes all of the snide little remarks at the end posts. Face it: the post that got all of this started was pretty bad. There were reasons for this. Everyone makes mistakes sometimes (my own spelling proves this often enough). So do you think that we can grow-up and leave this behind us? Clint ccorbin@xxx.com ------------------------------ From: arthurok@xxx.com (ARTHUR OKUN ) Date: Sat, 10 Feb 1996 00:23:01 -0800 Subject: Re: Multiprocessor system there are tricks using latches to expand ports on single chip micros look in the intel developement hand book . distributed processing is good i hear that down the road a bit all new us cars are going to use networked computers to run all their systems and save wire . ------------------------------ End of DIY_EFI Digest V1 #38 **************************** 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".