DIY_EFI Digest Friday, 6 September 1996 Volume 01 : Number 262 In this issue: FORTH ISBN Re: Ancient History Electronic Ignition Re: Knock sensor spectrum? Re: Electronic Ignition Re: DIY_EFI Digest V1 #259 Re: Knock sensor spectrum? Re: DIGIFANT the great re: Re: Electronic Ignition Check out the C31 DSK (was Re: Knock sensor spectrum?) Re: Manifold/throttle bodys-ED:-) Multispark ignition "computers" re: Re: Electronic Ignition Re: Knock sensor spectrum? Re: hi compressions: wasDIY_EFI Digest V1 #258 Ford 351W Intake Manifold Electronic Ignition Re: Ford 351W Intake Manifold Re: Ancient History Re: hi compressions: wasDIY_EFI Digest V1 #258 Re: Electronic Ignition Re: Knock sensor spectrum? re: Re: hi compressions: wasDIY_EFI Digest V1 #258 re: Electronic Ignition Vats Re: Electronic Ignition re: Ancient History re: Manifold/throttle bodys-ED:-) Re: Knock sensor spectrum? Re: Manifold/throttle bodys-ED:-) See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: David Redpath <101513.357@xxx.COM> Date: 05 Sep 96 06:03:56 EDT Subject: FORTH ISBN The book I mentioned 'FORTH: The New Model' is by Jack Woehr. The ISBN is 0-13-036328-6. hope that's useful. As far as The Hitachi H8 I talked about. more info available on http://www.hitachi.com ------------------------------ From: dave.williams@xxx.us (Dave Williams) Date: Wed, 04 Sep 1996 18:35:00 +0000 Subject: Re: Ancient History - -> If you run the injectors beyond 80% dwell, they become erratic and - -> the flow rates go to hell. Stay below 80% and you'll make your - -> engine much happier. I've hung injectors open for ten minutes at a time on the test bench without any trouble. - -> Also, if you're running above 80%, you can burn - -> your driver circuitry out prematurely. I've played with a Galant VR-4 with the DSM test unit. On the road at WOT it will run the injectors to 98%. I've observed 95% on a '90 Corvette with Diacom. Both of these cars survive extended periods at WOT at track events, and have for years. ====dave.williams@xxx.us========================DoD#978======= can you help me...help me get out of this place?...slow sedation... ain't my style, ain't my pace...giving me a number...NINE, SEVEN, EIGHT ==5.0 RX7 -> Tyrannosaurus RX! == SAE '82 == Denizens of Doom M/C '92== ------------------------------ From: "GEORGE LERM" Date: Thu, 5 Sep 1996 12:31:50 GMT-2 Subject: Electronic Ignition Hi Cool list! Does anyone know of any DIY_Electronic Ignition mailing lists. I would like to explore the options of experimenting with a distributorless ignition for my VW Beetle. Any suggestions,help or comments would be appreciated. ------------------------------ From: cloud@xxx.edu (tom cloud) Date: Thu, 5 Sep 1996 07:58:05 -0500 Subject: Re: Knock sensor spectrum? >At 07:00 PM 9/4/96 +0200, you wrote: >>Hello Walter >> >>You can have more informations about this problem by the application note: >> >>17. ENGINE KNOCK DETECTION USING TMS320C25 AND TMS320C30 DSPS >>APPLICATION REPORT >> >> spra039.pdf (329 KBytes) >> >Can this be put on one of the FTP sites or Web pages? > >Sandy > I downlowded this app (all 63 pages or so) yesterday. I can send it to anyone that wants it -- could also repose (sic?) it into some repository! tom ------------------------------ From: walter.kaufmann@xxx.ch (Walter Kaufmann) Date: Thu, 5 Sep 1996 15:09:09 +0200 Subject: Re: Electronic Ignition Hi George, I would be interested to in a eletronic ignition mailing list. My Austin Mini is waiting for an electronic distributerless ignition.... If you know more about a 'ign' list, I would be interested too! Thanks Walter ------------------------------ From: Jens Knickmeyer Date: Thu, 5 Sep 1996 15:55:35 +0200 (MET DST) Subject: Re: DIY_EFI Digest V1 #259 wrote: > > > >What's Digifant? > > > > > >RD > > > > Just another vw fuel system that was for all intents and purposes was > > propietary and short lived. I believe it was used on late 60's early > > 70's squarebeeks. The name was repulsive enough to keep me from ever > > learning about it. > > The Vanagon kept Digifant and four-speed transmissions and the leading > edge of automotive technology for many years (snicker). > > How could it not be a Bosch system, though? I know little about it, but it > was my understanding that Digifant bridged the gap between LJet and > Motronic (ie integrated spark but dumber brain) > > What is it really? > > -Dan Digifant is, as you said, a bridge between LJet and Motronic and handles ignition and injection. The injection system is the same as the Digijet which is also called L2-Jet. It was the first LJet which used digital instead of analog design. The L3-Jet is nearly the same, except that the ECU is mounted on the AFM. The Digifant's injection system is a MPI, all injectors are batched. Digifant includes an ignition which is based upon the Dignition. It controls dwell and timing, the supercharged engines and some high compression engines have a know sensor. The knock sensor's signal is filtered by an analog filter circuitry and is measured only in a small window after ignition (simply done by switching the filered signal to the MCU by a CD4066). The Digifant ECU is a "multi purpose" ECU, it can be used with a MAP or a MAF sensor, with or without knock sensor. MAP is used on the supercharged engines, MAF on the other ones (this goes for German VWs, situation might be different in other countries). When the Digifant came out in the early '80s, it used two MCUs, a 80xx and a 68HC05. Later, VW switched to one HC11 instead of using two MCUs. Digifant has an OBD which got more sophisticated over teh years of production. The first ECUs had a blink code output, later a high speed diagnostic interface was used. Digifant ECUs are produced by Bosch (small cases) and Siemens (large cases). Jens ('92 VW Polo-G40) ------------------------------ From: Sandy Date: Thu, 5 Sep 1996 09:26:02 -0700 Subject: Re: Knock sensor spectrum? How about posting it to John's FTP site? >>>You can have more informations about this problem by the application note: >>> >>>17. ENGINE KNOCK DETECTION USING TMS320C25 AND TMS320C30 DSPS >>>APPLICATION REPORT >>> >>> spra039.pdf (329 KBytes) >>> > ------------------------------ From: Todd King Date: Thu, 05 Sep 96 10:47:00 PDT Subject: Re: DIGIFANT the great <<< From: Mark Pitts Date: Wed, 4 Sep 1996 13:48:37 +-200 Subject: RE: d disease Durrr me dunno either, what is DIGIFANT? Mark >>> DIGIFANT was a great Mastodon that once lived in the Black Forest; Teutonic mythology claims that his weight was "over 10,000 stone" and height "over 100 hands". He was said to posses great digital design skills, due primarily to a tremendous memory capacity... Todd Todd_King@xxx.com ------------------------------ From: SRavet@xxx.com Date: Thu, 5 Sep 96 11:51:07 CDT Subject: re: Re: Electronic Ignition walter.kaufmann@xxx.ch (Walter Kaufmann) Wrote: | | Hi George, | | I would be interested to in a eletronic ignition mailing list. My Austin Mini | is waiting for an electronic distributerless ignition.... | | If you know more about a 'ign' list, I would be interested too! | | Thanks | Walter | | | You guys are on it. Despite the EFI in the name, this list is for engine management, including ignition. so fire away. Steve Ravet sravet@xxx.com Baby you're a genius when it comes to cooking up some chili sauce... ------------------------------ From: Rod Barman Date: Thu, 5 Sep 1996 11:15:49 UTC-0700 Subject: Check out the C31 DSK (was Re: Knock sensor spectrum?) Those of you thinking of fiddling with engine knock on a dsp should check out TI's el-cheapo C31 DSK. More info can be found at "http://www.ti.com/sc/c3xdsk" - --rod. - -- Rod Barman, IRIS IS-6 @ Laboratory for Computational Intelligence University of British Columbia rodb@xxx.ca ------------------------------ From: LotusM50@xxx.com Date: Thu, 5 Sep 1996 15:07:02 -0400 Subject: Re: Manifold/throttle bodys-ED:-) In a message dated 96-09-04 16:06:27 EDT, wright@xxx.gov (Dirk Wright) writes: >I remember my old alfa with the spica mechanical injection had one >throttle per cylinder. pretty cool. So does the Lotus Turbo Esprit, but with elctronic fuel injection.... ------------------------------ From: Fredrik Jeppsson Date: Thu, 5 Sep 1996 21:29:20 +0200 (MET DST) Subject: Multispark ignition "computers" Hello from Sweden, I am considering upgrading the stock Lucas/Bosch ignitiion in my 1988 EFI Range Rover (3.5 liter ex buick V8). I would really appreciate some opinions and words of experience on the performance / smoothness improvements after adding one of those boxes between the trigger device and the ignition amplifier. I am also interested in the effect of performance coils marketed by the same companies (Jacobs, MSD and others). Fredrik Jeppsson * FAE, Embedded development tools * * Nohau Elektronik AB, Malmoe, Sweden * * * * 1988 Range Rover EFI * * 1990 Citroen XM V6 * ------------------------------ From: John.Beggs@xxx. Beggs) Date: Thu, 5 Sep 96 13:05:56 PDT Subject: re: Re: Electronic Ignition >You guys are on it. Despite the EFI in the name, this list is for engine >management, including ignition. so fire away. Tim Drury wrote an excellent paper on a Digital Distributorless Ignition System. Try http://spbted.gtri.gatech.edu and look for Tim's name, etc. John W. Beggs, BC Hydro, 6911 Southpoint Dr., Burnaby, BC, V3N 4X8, Canada. Voice: (604)528-2776, FAX: (604)528-1883, EMail: john.beggs@xxx.ca ------------------------------ From: cloud@xxx.edu (tom cloud) Date: Thu, 5 Sep 1996 15:16:22 -0500 Subject: Re: Knock sensor spectrum? >How about posting it to John's FTP site? Be glad to .... what's it?? > >>>>You can have more informations about this problem by the application note: >>>> >>>>17. ENGINE KNOCK DETECTION USING TMS320C25 AND TMS320C30 DSPS >>>>APPLICATION REPORT >>>> >>>> spra039.pdf (329 KBytes) >>>> >> > > > ------------------------------ From: Todd Knighton Date: Thu, 05 Sep 1996 13:25:09 +0000 Subject: Re: hi compressions: wasDIY_EFI Digest V1 #258 John Faubion wrote: > > Actually the big reason for multivalve chambers is more area is exposed > around the valve to flow fuel. Two small valves have much more flow > capacity than 1 large valve but is more expensive that manufacture. That's also what Yamaha though, they went to 5 valves to get even more flow. They did pick up flow, but on the F1 motors the 4 valve engines made more power still. Point is. It's not all flow, but combustion chamber shape and flame propogation as well. Todd Knighton Protomotive Engineering ------------------------------ From: Mark Eidson Date: Thu, 5 Sep 1996 14:05:43 -0700 Subject: Ford 351W Intake Manifold Is there a stock or aftermarket EFI manifold similar to the 5.0 liter late model Ford for the 351W? me *************************************************************************** * Mark Eidson Voice: (602)752-6513 * * Staff Design Engineer Fax: (602)752-6000 * * Manager System Integration and * * Verification E-Mail: mark.eidson@xxx.com * * VLSI Technology, Inc. * * 8375 South River Parkway * * M/S 265 * * Tempe, Arizona 85284 * *************************************************************************** ------------------------------ From: "Tony Bryant" Date: Fri, 6 Sep 1996 09:11:45 +1200 Subject: Electronic Ignition Does the ignition condensor/capactitor serve any function other than to reduce arcing across points? Do I need one if I switch using a transistor? (with 400V zener clamp) Facts, not theories, please.. *********************************************************** * "Insanity is the only sane response to an insane world" * * >> bryantt@xxx.nz << * *********************************************************** ------------------------------ From: Matt Sale Date: Thu, 5 Sep 1996 16:30:51 -0500 (EST) Subject: Re: Ford 351W Intake Manifold > > Is there a stock or aftermarket EFI manifold similar to the 5.0 liter late > model Ford for the 351W? me Yes, look on the 95 full-size trucks and I think the SVO Ranger. Also look in the Ford Motorsports catalog. - -- Matthew D. Sale, IC Development Engineer, Delco Electronics Corp. msale@xxx.com/~msale '69 Mustang 351W 5-spd (13.656@xxx. All responses are my own and should not be mistaken for those of Delco Electronics or General Motors. ------------------------------ From: Jonathan Lloyd Date: Tue, 3 Sep 1996 20:54:30 +0100 Subject: Re: Ancient History In message , Dirk Wright writes >On Mon, 2 Sep 1996, Robert J. Harris wrote: >> >> Liquid fuel does not burn - period. It must be vaporized before it burns. > >Um, sorry. Gasoline vapor explodes, it does not burn. Liqiud gasoline >burns. Gasoline vapor ignited in a combustion chamber will cause > >**************************************************************************** >Dirk Wright wright@xxx.gov > Excuse the butt in but liquid fuel does burn, try throwing a match into a bowl of gasoline, and vapour does not neccessarily "explode". The chamber will be full of vapour and droplets of various sizes prior to spark. As the temp and pressure rise the oxygen in the air dissociates ( a very temp dependent effect) and provides the oxygen radicle neccessary for combination with the hydrocarbon mix. Explosion occurs when the temp is high enough to dissociate the hydrocarbons and is a function of "quality" i.e. octane rating in which case the whole cylinder contains free oxygen and free hydrocarbon radicals and the whole lot reacts at once. Bad news , knock , damage etc. The fuel should be a high enough octane rating to suppress dissociation. Reaction is then totally determined by the spark and a flame front is created. What is wanted is not the fastest burn possible but a good start and prolonged long enough to finish some way down the power stroke. The flame speed of the vapour for a given mixture is calculatable and reaches the cylinder walls quickly igniting the droplets as it goes. They continue to burn and any droplets too big will be exhausted without having provided all the power they could have done. - -- Jonathan Lloyd john@xxx.uk ------------------------------ From: Daniel Ridge Date: Thu, 5 Sep 1996 18:08:58 -0400 (EDT) Subject: Re: hi compressions: wasDIY_EFI Digest V1 #258 On Thu, 5 Sep 1996, Todd Knighton wrote: > John Faubion wrote: > > > > Actually the big reason for multivalve chambers is more area is exposed > > around the valve to flow fuel. Two small valves have much more flow > > capacity than 1 large valve but is more expensive that manufacture. > > That's also what Yamaha though, they went to 5 valves to get even more > flow. They did pick up flow, but on the F1 motors the 4 valve engines > made more power still. > Point is. It's not all flow, but combustion chamber shape and flame > propogation as well. Well, I don't think anybody thought that multivalves flow better per unit area of opening.... Todd's right about chamber shape and flame proopgation. Multivalves are a hack around the hard limits that geometry places on things -- we're constrained to have circular valves, it's tough to use real estate well when you are nesting circles(valves) in circles(cylinder(head)s). The multivalve people didn't want multivales -- they really wanted rectangular valves :). Two small valves have worse flow (per unit area) than one large valve, but you can get better aggregate flow with multivalves with a larger total area than would be possible with univalve configurations. - -Dan ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\___/~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Daniel Ridge | USRA CESDIS Research Minion, Beowulf Project | Code 930.5 email: newt@xxx. W274 tel: 301-286-3062 | Goddard Space Flight Center fax: 301-286-1777 | Greenbelt, MD. 20771 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\_|_/~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ http://cesdis.gsfc.nasa.gov/people/newt ------------------------------ From: Daniel Ridge Date: Thu, 5 Sep 1996 18:12:04 -0400 (EDT) Subject: Re: Electronic Ignition On Fri, 6 Sep 1996, Tony Bryant wrote: > Does the ignition condensor/capactitor serve any function > other than to reduce arcing across points? Do I need one > if I switch using a transistor? (with 400V zener clamp) Points? Eh? :) > > Facts, not theories, please.. I don't know that this is the best place (or even should be) for facts. There are too many (like standards) to choose from. - -Dan ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\___/~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Daniel Ridge | USRA CESDIS Research Minion, Beowulf Project | Code 930.5 email: newt@xxx. W274 tel: 301-286-3062 | Goddard Space Flight Center fax: 301-286-1777 | Greenbelt, MD. 20771 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\_|_/~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ http://cesdis.gsfc.nasa.gov/people/newt ------------------------------ From: Sandy Date: Thu, 5 Sep 1996 15:46:55 -0700 Subject: Re: Knock sensor spectrum? At 03:16 PM 9/5/96 -0500, you wrote: >>How about posting it to John's FTP site? > >Be glad to .... what's it?? > The site address (at last recollection) ftp://efi332.eng.ohio-state.edu Place the files in the 'Incomming' directory Sandy ------------------------------ From: SRavet@xxx.com Date: Thu, 5 Sep 96 18:17:19 CDT Subject: re: Re: hi compressions: wasDIY_EFI Digest V1 #258 Daniel Ridge Wrote: | Todd's right about chamber shape and flame proopgation. Multivalves are a | hack around the hard limits that geometry places on things -- we're | constrained to have circular valves, it's tough to use real estate well | when you are nesting circles(valves) in circles(cylinder(head)s). The | multivalve people didn't want multivales -- they really wanted rectangular | valves :). This might be a dumb question, but why not non-circular valves? I guess they wouldn't be able to spin. Is that a problem? I can see corners being bad, but what about a nice oval shape? - --steve Steve Ravet sravet@xxx.com Baby you're a genius when it comes to cooking up some chili sauce... ------------------------------ From: SRavet@xxx.com Date: Thu, 5 Sep 96 18:24:16 CDT Subject: re: Electronic Ignition "Tony Bryant" Wrote: | | Does the ignition condensor/capactitor serve any function | other than to reduce arcing across points? Do I need one | if I switch using a transistor? (with 400V zener clamp) | | Facts, not theories, please.. | | *********************************************************** | * "Insanity is the only sane response to an insane world" * | * >> bryantt@xxx.nz << * | *********************************************************** | Are you talking about electronic ignition or point ignition? I've never actually worked on a point ignition (not that old), but I'm pretty sure the condensor stores a charge, which is discharged thru the coil to make a spark. That is CD (capacitive discharge) ignition. Electronic ignitions usually charge the coil primary during the dwell period, interrupting the charge causes the field to collapse and generate a spark, no capacitor needed. HEI ignitions (from GM) are electronic, but have a condensor. The only purpose of the condensor is noise suppression for the radio, however. The car will run fine without it. - --steve Steve Ravet sravet@xxx.com Baby you're a genius when it comes to cooking up some chili sauce... ------------------------------ From: peter paul fenske Date: Thu, 05 Sep 1996 15:29:44 -0700 Subject: Vats Hello Guys Built a Vats defeat. Used a 555 driving a 3904 via a 2.7K resistor. This is because the ECM wants to see a open collector driving the passkey port. The components I used were a 15K for Ra, a 50k pot and a 68K resistor in series for Rb, and a 0.2 ufd timing cap. Midway on the pot produced the 30 Hz. Works to 92 on F body. Just to make it simplier for the next guy. By the way the new Passkey II can't be quite as easily defeated. There is a adaptive algorithm in this one. Later guys: peter ------------------------------ From: Darrell Norquay Date: Thu, 5 Sep 1996 20:11:00 -0700 (PDT) Subject: Re: Electronic Ignition At 09:11 AM 9/6/96 +1200, you wrote: >Does the ignition condensor/capactitor serve any function >other than to reduce arcing across points? Do I need one >if I switch using a transistor? (with 400V zener clamp) The cap also damps ringing of the ignition coil when the points open. Most electronic ignitions do not have one, although it probably won't hurt to leave it in. regards dn dnorquay@xxx.com ------------------------------ From: RABBITT_Andrew@xxx.au Date: Fri, 6 Sep 1996 11:11:28 est Subject: re: Ancient History >cylinder contains free oxygen and free hydrocarbon radicals and the >whole lot reacts at once. Bad news , knock , damage etc. Not exactly true. Combustion pressure, temperature and radiation are required to initiate knock, which is where areas in the combustion chamber auto-ignite causing several flame fronts to develop uncontrolled. >What is wanted is not the fastest burn possible but a good >start and prolonged long enough to finish some way down the power >stroke. In theory, you want as fast a burn-rate as possible (to minimise BSFC), however the pressure rise rate will limit this. High pressure rise rates will excite the block, head etc at various natural frequencies, increasing the engine noise. (Diesel engines are the extreme of this) > ....quickly igniting the droplets as it goes. They continue to burn >and any droplets too big will be exhausted without having provided >all the power they could have done. Large fuel droplets cause soot formation. ------------------------------ From: RABBITT_Andrew@xxx.au Date: Fri, 6 Sep 1996 11:30:32 est Subject: re: Manifold/throttle bodys-ED:-) >In a message dated 96-09-04 16:06:27 EDT, wright@xxx.gov (Dirk >Wright) >writes: > >>I remember my old alfa with the spica mechanical injection had one >>throttle per cylinder. pretty cool. > >So does the Lotus Turbo Esprit, but with elctronic fuel injection.... So do all EFI Alfa 33/145/146 boxer engines. Does anyone know what would happen if you joined all the chokes together on the down-stream side of each throttle, kind of like forming a mini-plenum for improving balance robustness at low throttle openings, but still allowing the correct runner design and plenum volume up-stream of the blades for WOT performance? Anyone tried this? Any theories? ------------------------------ From: DJohn77284@xxx.com Date: Fri, 6 Sep 1996 02:53:32 -0400 Subject: Re: Knock sensor spectrum? Tom, I'd appreciate a copy of the application note spra039.pdf if possible. Just some bedtime reading - like you do..... Thanks Dave DJohn77284@xxx.com ------------------------------ From: DJohn77284@xxx.com Date: Fri, 6 Sep 1996 03:21:07 -0400 Subject: Re: Manifold/throttle bodys-ED:-) Yamaha, again, have used this method in the past on some of there air-cooled motrocycle engines. They called it 'YICS' - Yamaha Induction Control System. I don't know whether there were any real benefits or that it was just a gimick. They also tried seven valve heads - four inlet, three exhaust - before settling with five valves. Regards, Dave DJohn77284@xxx.com ------------------------------ End of DIY_EFI Digest V1 #262 ***************************** 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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