DIY_EFI Digest Thursday, 25 January 1996 Volume 01 : Number 021 In this issue: Re: Ford EEC-IV Ignition Module Simulating an IC engine ... inconagain RE: Cyberdyne A/F meter RE: Cyberdyne A/F meter Re: Engine Reversal and EFI Identify This ECM Re: Engine Reversal and EFI See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: imonkare@xxx.fi Date: Wed, 24 Jan 1996 14:22:09 +0200 (WET) Subject: Re: Ford EEC-IV Ignition Module > =20 > >Hi! Could someone help me with a Ford EEC-IV TFI ignition module of a=3D= 20 > >Ford Sierra (with HALL sensor and european ECU). I=3DB4ve built a contro= l=3D20 > >unit of a Siemens SAB80C517 microcontroller and now I have some=3D20 > >difficulties in controlling the IM. > > > >I=3DB4ve come this far: > > > >output ------- ------ > >of | | > >HALL |_________| > > / \ > > / Start advance (say 12 deg BTDC) > > "Max" advancd > > (about 90 deg BTDC) > > > >"Start advance" is the point where EEC-IV fires when starting the engine= .=3D > >=3D20 > >Even if the ECU is disconnected the IM fires at "start advance" (limp=3D= 20 > >home). The ECU tells to the IM when to fire with a rising edge. I tried= =3D20 > >that too. I switched the ignition signal OFF at "max advance" an ON when= =3D20 > >I wanted to fire, I could fire only AFTER "start advance". When I had an= =3D20 > >advance of about 30 deg the IM fired at "start advance". > > > >So, a few questions: Am I so far right? =20 > From the way you've described your TFI unit functionality, my guess > is that it's not a Ford TFI unit but a Ford EDIS unit. This takes > in the 36-1 signal from the VRS sensor (not HALL) and converts it > to a signal with 50% dutycycle and rising edges at 10 deg BTDC > for each cylinder which it feeds through to the EEC-iv. In return > the EEC-iv sends out a required spark advance signal every firing > event where the width of the pulse sent relates to the spark > advance required. The pulse timing from the ECU does NOT affect the > ignition timing. After a certain number of firing events without > receiving a valid advance pulse from the ECU, the EDIS switches to > it's default spark advance which is 10 deg BTDC. The EDIS unit of > course drives the standard Ford twin-coil pack (wasted spark).=20 >=20 >=20 > >Does ECU take care of dwell? With the falling edge? How to calculate tha= t? > > >=20 > Dwell is handled automatically by the EDIS unit, but rate of > change of spark advance must be limited by the ECU to a few degrees > per firing event to avoid screwing it up. =20 Brian, I=B4m not sure about the name (TFI or EDIS), but it uses a HALL sensor for= =20 sure. I have the system installed on my car and with EEC-IV ECU it works=20 fine. Ilari Monkare, imonkare@xxx.fi ------------------------------ From: Land Shark Date: Wed, 24 Jan 1996 08:20:46 -0700 (MST) Subject: Simulating an IC engine ... At 01:03 AM 1/24/96 -0500, you wrote: >I am doing a simulation of an internal combustion engine given the >spark firing and injector signal. >Sources on a model for an IC engine would be >helpful. Thank you. Guys, please keep me in the loop on this .. I need to simulate a few BMW 6's also .. Jim Conforti ------------------------------ From: PRodda@xxx.com Date: Wed, 24 Jan 1996 07:35:14 -0800 Subject: inconagain =========================== EMAIL: paul.rodda@xxx.uk =========================== tks for the confirmation, peter. not trying to knock the ICON unit at all - was simply curious to know just how much it is capable of doing/not doing. thanks for the response. cheerio paul r. =========================== EMAIL: paul.rodda@xxx.uk =========================== ------------------------------ From: Mike Wesley - SLIP Date: Wed, 24 Jan 1996 11:46:10 -0500 (EST) Subject: RE: Cyberdyne A/F meter On Sat, 20 Jan 1996, Jim Pearl wrote: > I don't mean to sound skeptical of your results but if the Cyberdyne = > gauge is using a standard sensor it's nearly impossible for it to do the = > things you've described. The readout from the "standard" sensor(s) is = > NOT linear and they operate more like a light switch than any sort of = > A/F sensor (so I've been told many times). Just out of curiosity - did = > you ever compare the readouts given by the gauge with a true A/F meter = > such as a Horiba? If they compared closely I'd believe it otherwise I'm = We did just that. I compared 5 different 'guages' with 50 O2 sensors against a Horbia, Bosch LA2, and NTK 5001 and none of them were even close. We would see A/F errors of up to 3 full points off. The 'guage' would read '12:1' and actual would be more like 9:1! Of course it would vary for sensor to sensor, but out of the 50 sensors we tested, NONE were close. They were real good around stoich, but above or below that. O2 sensors used were from Bosch, Tomco, and NTK. The stock O2 sensors are too non-linear away from stoich to be useful. Of course if one has spent money on a 'guage' it's hard to convice them otherwise. Similar testing was also done at Bosch with the same results (compare aftermarket 'guage' to real A/F ratio measurement devices). Mike... ------------------------------ From: Timothy Coste Date: Wed, 24 Jan 1996 14:37:42 -0500 Subject: RE: Cyberdyne A/F meter Hey Mike, Be careful at 9:1. I was flipping through our Horiba manual and it says that the sensor life can be measured in tens of hours when run that rich. I can't quote the numbers right now (it was actually late last week I was reading up on it) but the way rich running just kills the poor suckers. And our university budget can't take replacing $900 sensors once a week. Hopefully your budget is better than ours though. :) Just though I'd mention it in case you weren't aware. Tim Coste tlcoste@xxx.edu ------------------------------ From: "Clinton L. Corbin" Date: Wed, 24 Jan 96 19:25:36 PST Subject: Re: Engine Reversal and EFI >down. Often twin engine installations in boats run the engines in >opposite directions, so you might look into SBC marine setups to see if >a reverse direction engine is produced, and what they've done to >support it. > >/Bill My understanding of the twin (and triple) engine installations in off-shore power boats is that both (or all three) engines turn in the same direction. The only difference is that the outdrive (be it sterndrive, v-drive, or other) is geared for reverse rotation. Just my two bits... Clint ------------------------------ From: Bob Valentine Date: Wed, 24 Jan 1996 23:06:12 -0500 (EST) Subject: Identify This ECM I just picked up what is supposed to be a ECM and engine harness from a TPI Camaro. I'm 99% sure it's a TPI since it's got 8 injector connectors. There does not seem to be once for a cold start injector. Unknown if it's from a 305 or a 350. ECM has a two cavity connector. Can anyone identify it from these numbers: Service Number: 1227165 Sticker on ROM: Delco ABYA 5400 Sticker inside box: 5088365 Barcoded sticker on harness connector: 310038212158301 Are there any simple tests I can do on the unit to see if it's alive, aside from powering it up and hooking up a check light? I don't have access to a TPI car to try it in. Intended home would be on a 350 Olds.... pre-home-built unit. 8^) I crossposted this since it could be answered in either/or mailing list... --> Bob Valentine <-- --> ravalent@xxx.com <-- "Hard Acceleration Saves Costly Aggravation" ------------------------------ From: Bob Valentine Date: Wed, 24 Jan 1996 23:13:16 -0500 (EST) Subject: Re: Engine Reversal and EFI On Wed, 24 Jan 1996, Clinton L. Corbin wrote: > >down. Often twin engine installations in boats run the engines in > >opposite directions, so you might look into SBC marine setups to see if > >a reverse direction engine is produced, and what they've done to > >support it. > > > >/Bill > My understanding of the twin (and triple) engine installations in off-shore > power boats is that both (or all three) engines turn in the same direction. > The only difference is that the outdrive (be it sterndrive, v-drive, or > other) is geared for reverse rotation. Just my two bits... I've seen it done both ways, but most commonly one motor is reversed. Every reverse-rotation Crusader marine engine I've seen is PLASTERED with caution stickers about its rotation and not to set the timing too far back. A marine mechanic I spoke to said the only difference between a CW and a CCW motor was the cam and the starter - makes sense. He also mentioned that the reverse motors usually had a hotter cam since they didn't make as much power as their normal rotation cousins. --> Bob Valentine <-- --> ravalent@xxx.com <-- "Clinging Tenaciously to the Trailing Edge of Technology" ------------------------------ End of DIY_EFI Digest V1 #21 **************************** 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".