DIY_EFI Digest Tuesday, 10 December 1996 Volume 01 : Number 377 In this issue: Re: DIY_EFI Digest V1 #376 Re: Flywheel/Encoder patterns Re: Flywheel/Encoder patterns Re: Flywheel/Encoder patterns Re: Flywheel/Encoder patterns Re: Forwarded: Re: Flywheel encoder patterns Re: eddy current brake Re: eddy current brake Re: Injector duty cycles new engine Re: Flywheel/Encoder patterns Re: Injector duty cycles Ford Quad Plug coils Re: new engine Re: Ford Quad Plug coils Re: Ford Quad Plug coils See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: talltom Date: Mon, 09 Dec 1996 04:20:04 -0800 Subject: Re: DIY_EFI Digest V1 #376 > > From: RABBITT_Andrew@xxx.au > Date: Mon, 9 Dec 1996 11:54:00 est > Subject: Forwarded: Engine braking???? > > this sounds very dubious to me! Well, there's definetly a rat running around here somewhere! > For a start, you'd want to advance your timing to involve the > compression stroke, and what then about knock control? I suspect that the amount of advance could be tailored to brake but not necessarily knock. > On the other hand, if you're off the loud pedal, you're more likely to > be in over-run fuelling cut mode, therefore spark is not likely to do > much for you. That may be part of the key, because the braking doesn't occur until the brake is just tapped, not applied. This could trigger a switch t start it, with a provision to only work over x mph/rpm? Anyhow all I know is that he's had the thing for months and several thousand miles and didn't discover it until the hunting trip. I guess he had about 8000# trailer and going downhill onw tap on the brake and speed would not increase, period. Also without the trailer in 4x4 in low range, low gear(auto) one tap on the brake and it would hold 5mph on a 10% grade. This is what facinated me, as I have a 4x4 rig with lower gears, bigger engine and essentially the same tranny and there's no way mine can be geared down slow on a downhill. I was just hoping maybe one of the factory guys might pipe up with some explanation, but that doesn't seem to be the case, and I'm not interested enough to pursue it. > - -- >>---------------------------------CUT------------------------------------------<< How long will it take Clinton's lies to to put him where he belongs? (he belongs in line for welfare as the door closes with a sign that says "closed due to lack of funds".) Let somebody who can stomach him support him. Don't blame me, I voted for Harry Browne! ------------------------------ From: kleenair@xxx.com Date: Mon, 09 Dec 1996 07:35:24 -0800 Subject: Re: Flywheel/Encoder patterns RABBITT_Andrew@xxx.au wrote: > > How about instead, using a programmeable down counter which you load > with your injector pulse width counter and trigger both the counter > and the injector turn-on with your encoder/angle count. Then the > counter just counts to zero and turns your injector off. >That's a great idea. > Don't forget you'll might need some voltage compensation for your > injector turn-on and off delays. This will make resolution issues > even more important to you. I already plan to use a injector PW correction vs. battery voltage table. Thanks, Mazda > Andrew Rabbitt > > PS: these numbers came from data just lying around. Don't take them ------------------------------ From: Chris Howard Date: Tue, 10 Dec 1996 00:45:06 +1100 Subject: Re: Flywheel/Encoder patterns At 15:33 12/8/96 -0800, you wrote: > Pardon my ignorance, but what effect does a magnet have on a non >metallic element like aluminum or copper. > How's it work? > And what kind of drag can you expect from such a device? > I'll presume you know that aluminium and copper are metals and you in fact meant non-ferrous elements. :) Here's what I remember from physics lectures: Faraday's law states that a changing magnetic field will induce an emf in a conductor. If the conductor forms a circuit, a current will flow. This is how a generator works. | ________ | | Magnet | |________ | (ascii amateur) ---------------| | | | Consider a metal disk which is rotating on a shaft with a magnet at right angles to the disk on one side. The disk will experience a changing magnetic field and hence an emf will be induced in it. There are of course many paths for current to flow within the disk as it is a conductor. Circular currents flow in the disk and, due to the finite resistance of the metal, energy is dissipated as heat. The kinetic energy of the disk is changed to heat energy and the disk slows down. EMF = electromotive force (V) Hope this helps, Chris Howard Computer Science University of New South Wales email: s2184002@xxx.au Web: http://www.usyd.edu.au/~choward - Aussie Touring Car Action Microsoft-Where do you want to crash today? ------------------------------ From: MikeTurner@xxx.com (Mike Turner) Date: Mon, 09 Dec 1996 09:01:22 -0500 Subject: Re: Flywheel/Encoder patterns On the problem of being in mid-update and getting weird results, you could use two sets of tables with a pointer to the current table. The pointer is used by the interrupt handlers. The foreground calculation routine uses the table the pointer does not point to and updates the pointer when the calcs are done to point to the new table data. The expense here is using indexed addressing vs. direct addressing. ------------------------------ From: cloud@xxx.edu (tom cloud) Date: Mon, 9 Dec 1996 08:25:06 -0600 Subject: Re: Flywheel/Encoder patterns >Chris Morriss wrote: >> >> A neat and very reliable solution to taking up the backlash is to mount >> an eddy current brake on the shaft. Much easier than providing viscous >> drag. All you need is a plain aluminium or copper disk rotating in the >> gap of a horse-shoe magnet. Like a old electricity meter. (If you had >> the rotating disk meters in the US) The principle was also used as the >> speed control a#on the old but revered Garrard 401 record turntable. > > Pardon my ignorance, but what effect does a magnet have on a non >metallic element like aluminum or copper. > How's it work? > And what kind of drag can you expect from such a device? > >Todd Knighton Todd, I think 'analog' speedometers are based on this principle, as is my reloading scale. ... speedo: round brass disk attached to speedo pointer and to return sproing. disc magnet connected to speedo shaft. rotating magnet induces cemf (counter emf) in brass disk, which acts as a shorted turn thereby inducing a magnetic field opposing the rotating magnet, making the speedo pointer move. [understand that this is what I think happens -- comes from working with the speedo on my /90 Triumph 650 Bonneville -- those dratted things vibrated the instruments apart after 10 or 20 thousand miles. When I rebuilt the speedo, I only found a brass disk and circular magnet as described above. All else is my conjecture.] ... reloading scale -- and every triple beam balance I've seen in chemistry labs. An aluminum tab is hung on the end of the balance beam in the field of a magnet mounted to the balance frame. The movement of the tab through the magnet works like the speedo above, effectively dampening the movement of the beam so readings can be taken quicker. Tom Cloud ------------------------------ From: Stephen Dubovsky Date: Mon, 9 Dec 1996 09:26:56 -0500 Subject: Re: Forwarded: Re: Flywheel encoder patterns At 11:25 AM 12/9/96 est, you wrote: > >one of the problems you will run into with a hall-effect sensor is >the tooth width. Most sensor will switch low several mm before the >centre of the sensor and the tooth edge coincide, and switch high >again several mm afterwards. This will limit your tooth width and >hence your resolution for a given diameter. We find that at about 220 >mm dia (flywheel size), the best H-E sensor we can get will allow us >60 teeth without resorting to teeth that look like feeler gauges. > >Andrew Rabbitt > This is simply a function of the hall effect sensor you are using, the magnetic field, and the geometry of the configuration. (I assume you have the standard setup, a magnet and sensor placed around the gear so that a gear tooth 'closes' the loop.) You can either go find a less sensitive detector (or use an analog one w/ a different trip point) or reduce the magnetic field. (either move it farther from the wheel, get a smaller one, or 'short-circuit' some of its field w/ ferrous material). SMD - -- Stephen Dubovsky dubovsky@xxx.edu 95 Yamaha FZR600 83 Porsche 911SC 84 Jeep Cherokee ------------------------------ From: Todd King Date: Mon, 09 Dec 96 08:54:00 PST Subject: Re: eddy current brake <<< Pardon my ignorance, but what effect does a magnet have on a non metallic element like aluminum or copper. How's it work? And what kind of drag can you expect from such a device? Todd Knighton Protomotive Engineering >>> The magnet causes a drag force on the non-magnetic rotating disk (in this case) because of currents induced by the motion of the disk through the magnetic field; the currents "swirl" (thus the eddy term) about and dissipate as heat due to the small amount of resistance in the conducting disk. But of course a current in a conducter also generates a magnetic field so you get the drag force. It's really neat- you can brake the rotating disk without contacting it. If you happen to have an old hard drive platter laying around you can demo the effect. Give the platter a good spin and just bring a magnet close to the surface of the upper disk. You'll see the thing slow noticeably. BTW, if you have an older model drive dig out the (big) magnets from its arm motion control assy; you'll be Astonished by how strong they are if you have never seen these magnets before. Put two of them together (don't get your finger caught as they snap together!) and you will not be able to pull them apart without sliding them parallel! Anyway I think that another app for eddy current brakes was the diesel-electric locomotive? Todd Todd_King@xxx.com ------------------------------ From: Stephen Dubovsky Date: Mon, 9 Dec 1996 14:46:58 -0500 Subject: Re: eddy current brake At 08:54 AM 12/9/96 PST, you wrote: ... > BTW, if you have an older model drive dig out the (big) magnets from its arm > motion control assy; you'll be Astonished by how strong they are if you have > never seen these magnets before. ... That's nothing, go find a state of the art perm magnet synchronous machine (brushless DC in laymans terms) and get the mags off the rotor. Technology gets these things over 1.2T in a 1.5x0.75x0.125 package. They will demagnetize every other type of magnet I have ever seen. They are also explosive if machined. Fun stuff;) SMD - -- Stephen Dubovsky dubovsky@xxx.edu 95 Yamaha FZR600 83 Porsche 911SC 84 Jeep Cherokee ------------------------------ From: Roger Feingold Date: Mon, 9 Dec 1996 20:19:36 +0000 Subject: Re: Injector duty cycles Thanks for your answer. I got different numbers than you, but I still was wondering if anyone had some test data. I figured 467cc of air per cylinder per intake stroke. At 5k rpm that's 25.3g/s. 12.6:1 A/F is 2g/s of fuel. 2x60x60/454 = 15.86 lb/hr. This assumes 100% VE. At 6k rpm would be even higher, 19.11 lb/hr, this is why I thought it would be maxed out. Roger. ------------------------------ From: cloud@xxx.edu (tom cloud) Date: Mon, 9 Dec 1996 16:39:24 -0600 Subject: new engine I sent the following to the Bronco list -- may not be efi related (though it's my test bed for my efi experiments) -- but, I wanted any advice I can get. I don't claim to be an expert on engines. I am replacing the 351W in my '82 Bronco. It has an Edelbrock Performer manifold and Holley ProJection 670 cfm efi. =============== text of earlier message ================= I've taken the plunge. Since June, when my hoss's engine broke, I've been saving my money and doing research -- checked into 460's, SVO's, rebuilds, doing it myself, buying out of NHRA mag, or from PAW. To get block machined, forged pistons, c-moly rod and crank bolts, roller timing chain, new cam, lifters, etc was $1400 to $1600. Couldn't get PAW to give me straight answers or to supply what I wanted (even with ad that says "available in all standard comp ratios"). Was an ad in last Sunday's paper with a guy listing a complete 460, newly rebuilt, complete with intake & exhaust manifold, heads, carb, water pump, oil pump, pan for Bronco for $1500. Thought seriously about that one. Wanted the SVO 346 hp engine that cost ~$3200, but, even after I save the moola, don't know if I could really face the SO. Went Friday and bought "Lightning" short block from Ford SVO for ~ $1380 ($1492 with tax). It's what I want. Brand new, no used parts. Don't have to worry who or what did a rebuild, or what parts were used. Don't have to worry about all the miscellaneous doo-dads to put the 460 in, not to mention the increased fuel consumption. Can build it up to almost what I had wanted to buy for about $700 less. At any rate, check out SVO. Some of their prices are changing as of Jan 1. For example, the SB I just bought is going up to $1795, but GT-40 heads are dropping in price to $450 each. Also, they are introducing a GT-40X head that is supposed to outperform DART heads. If you're interested, here's a recap of my study of SVO 351W engines: ("Lightning" is short block, others are long blocks) 'Litnin' 351 GT-40 SVO 351 HO-SVO hp: 310 @xxx. 346 @ 5750 385 @ 5750 torque: 364 @ 4520 377 @ 4500 cam: intake: 260 ......... 290 220 @xxx.050 exhaust:274 . . . . 300 230 @xxx.050 lift: .444 .491/.509 .520 C.R. 8.8:1 9.0:1 9.0:1 head: GT-40 GT-40 GT-40 Al 'turbo swirl' comb. ch. volume 65.5 cc 65.5 cc 64 cc valves: .. int. 1.84 1.84 1.94 .. exh. 1.54 1.54 1.54 int. vol: ... ... 160 cc exh. vol: ... ... 53 cc manifold: 65 mm TB Performer RPM Victor Jr. carb: 'Motorsport Induction' 750 cfm Holley 750 cfm Holley headers: unknown Dyno Dyno Suggestions for headers, rockers, push rods, etc are in order, please. Also, I need a damper. Ford price ~ $100 -- good deal or not? Also need water and oil pump. Why does everyone recommend hi-vol oil pump? Need motor mounts, I guess .... would seem stoopid to put almost double the hp onto mounts that are probably 250,000 miles old. Is there anything else I'm missing (I'm anxious to get back inna da saddle). .......................................... BTW, If you really wanna make POWER: 460 "Cobra Jet" SVO complete engine with intake, heads, forged rods hypereutectic pistons, nodular crank, valve covers, damper, distributor, oil & water pumps, .... Makes 560 hp @xxx. $ 5200 I guess I'm a believer ..... you can't build it yourself for less, or even the same money as a 'kit' motor. Now, anyone looking for a 'seasoned' 351W with one piston missing upper ring land ??? Tom Cloud ------------------------------ From: Joao Carlos Silva Date: Mon, 9 Dec 1996 22:45:37 +0000 (GMT) Subject: Re: Flywheel/Encoder patterns On Tue, 10 Dec 1996, Chris Howard wrote: > At 15:33 12/8/96 -0800, you wrote: > > > Pardon my ignorance, but what effect does a magnet have on a non > >metallic element like aluminum or copper. > > How's it work? > > And what kind of drag can you expect from such a device? > > > > I'll presume you know that aluminium and copper are metals and you in fact > meant non-ferrous elements. :) > > Here's what I remember from physics lectures: > > Faraday's law states that a changing magnetic field will induce an emf in a > conductor. If the conductor forms a circuit, a current will flow. This is > how a generator works. > > | ________ > | | Magnet > | |________ > | (ascii amateur) > ---------------| > | > | > | > > Consider a metal disk which is rotating on a shaft with a magnet at right > angles to the disk on one side. The disk will experience a changing > magnetic field and hence an emf will be induced in it. There are of course > many paths for current to flow within the disk as it is a conductor. > Circular currents flow in the disk and, due to the finite resistance of the > metal, energy is dissipated as heat. The kinetic energy of the disk is > changed to heat energy and the disk slows down. I belive also that these currents are called by the English as Eddy currents and by the French as Focou currents (or something like that). If the disk is ferromagnetic the slowing down is much faster. As usual... hope this help (also hope that i'm not wrong) Joao Carlos Silva deec273@xxx.pt ------------------------------ From: Mazda Ebrahimi Date: Mon, 09 Dec 1996 18:49:38 -0500 Subject: Re: Injector duty cycles Roger Feingold wrote: > > Thanks for your answer. I got different numbers than you, but I still was > wondering if anyone had some test data. I figured 467cc of air per cylinder > per intake stroke. At 5k rpm that's 25.3g/s. 12.6:1 A/F is 2g/s of fuel. > 2x60x60/454 = 15.86 lb/hr. This assumes 100% VE. At 6k rpm would be even > higher, 19.11 lb/hr, this is why I thought it would be maxed out. > > Roger. Hi Roger, The peak efficiency number that is always thrown around conversations is 80% (and that is at peak torque which is at a lower RPM). There are some trick production engines that easily top 80%, but I don't know if the 2.8L is one of them. At any rate, my point is that after peak torque, your VE goes down, and from what I remember of my '88 Beretta with the 2.8 MPFI, power drops drastically past 5500 RPM. I have a chassis dyno, but unfortunately I sold my Beretta last year, so I can't be of any assistance. Best Regards, Mazda ------------------------------ From: Sandy Date: Mon, 09 Dec 1996 16:28:35 -0800 Subject: Ford Quad Plug coils Does anyone have any information on the Quad plug coil assembly on the late model Ford 4.6's? I have seen them in stangs, and the lincoln. Sandy ------------------------------ From: Mark Eidson Date: Mon, 9 Dec 1996 17:44:06 -0700 Subject: Re: new engine What type of intake manifold are you looking at? I assume you are going to use some sort of EFI. Are there manifolds similar to the 5.0 available for the 351W? I've seen production manifolds in boats that look like 5.0 units but are 5.7. Would these work on the older 302/351 style heads? If so where can one purchase them? I'm using a Performer RPM with a 700 CFM Holley Digital Pro-jection 4di with laptop control on my current engine. It has a crane hydraulic roller cam, @xxx.544, with 9.0:1 compression with rebuilt, hand ported 64cc cast iron heads. I have a 351 block sitting on the garage floor and want to make a sequential port injection system for it to bolt into my current setup. me At 04:39 PM 12/9/96 -0600, you wrote: >I sent the following to the Bronco list -- may not be efi related >(though it's my test bed for my efi experiments) -- but, I wanted >any advice I can get. I don't claim to be an expert on engines. >I am replacing the 351W in my '82 Bronco. It has an Edelbrock >Performer manifold and Holley ProJection 670 cfm efi. > > >=============== text of earlier message ================= > >I've taken the plunge. Since June, when my hoss's engine broke, I've >been saving my money and doing research -- checked into 460's, SVO's, >rebuilds, doing it myself, buying out of NHRA mag, or from PAW. > >To get block machined, forged pistons, c-moly rod and crank bolts, >roller timing chain, new cam, lifters, etc was $1400 to $1600. >Couldn't get PAW to give me straight answers or to supply what I >wanted (even with ad that says "available in all standard comp >ratios"). Was an ad in last Sunday's paper with a guy listing >a complete 460, newly rebuilt, complete with intake & exhaust >manifold, heads, carb, water pump, oil pump, pan for Bronco for >$1500. Thought seriously about that one. > >Wanted the SVO 346 hp engine that cost ~$3200, but, even after >I save the moola, don't know if I could really face the SO. > >Went Friday and bought "Lightning" short block from Ford SVO for >~ $1380 ($1492 with tax). It's what I want. Brand new, no used >parts. Don't have to worry who or what did a rebuild, or what >parts were used. Don't have to worry about all the miscellaneous >doo-dads to put the 460 in, not to mention the increased fuel >consumption. Can build it up to almost what I had wanted to >buy for about $700 less. > >At any rate, check out SVO. Some of their prices are changing >as of Jan 1. For example, the SB I just bought is going up to $1795, >but GT-40 heads are dropping in price to $450 each. Also, they >are introducing a GT-40X head that is supposed to outperform >DART heads. > >If you're interested, here's a recap of my study of SVO 351W engines: >("Lightning" is short block, others are long blocks) > > 'Litnin' 351 GT-40 SVO 351 HO-SVO > >hp: 310 @xxx. 346 @ 5750 385 @ 5750 >torque: 364 @ 4520 377 @ 4500 > >cam: > intake: 260 ......... 290 220 @xxx.050 > exhaust:274 . . . . 300 230 @xxx.050 > lift: .444 .491/.509 .520 > >C.R. 8.8:1 9.0:1 9.0:1 > > >head: GT-40 GT-40 GT-40 Al 'turbo swirl' >comb. ch. > volume 65.5 cc 65.5 cc 64 cc >valves: > .. int. 1.84 1.84 1.94 > .. exh. 1.54 1.54 1.54 > >int. vol: ... ... 160 cc >exh. vol: ... ... 53 cc > >manifold: 65 mm TB Performer RPM Victor Jr. >carb: 'Motorsport Induction' 750 cfm Holley 750 cfm Holley >headers: unknown Dyno Dyno > > >Suggestions for headers, rockers, push rods, etc are in order, please. >Also, I need a damper. Ford price ~ $100 -- good deal or not? Also >need water and oil pump. Why does everyone recommend hi-vol oil pump? >Need motor mounts, I guess .... would seem stoopid to put almost double >the hp onto mounts that are probably 250,000 miles old. > >Is there anything else I'm missing (I'm anxious to get back inna da saddle). > >.......................................... >BTW, If you really wanna make POWER: > >460 "Cobra Jet" SVO complete engine with intake, heads, forged rods >hypereutectic pistons, nodular crank, valve covers, damper, distributor, >oil & water pumps, .... Makes 560 hp @xxx. > $ 5200 > >I guess I'm a believer ..... you can't build it yourself for less, or >even the same money as a 'kit' motor. > >Now, anyone looking for a 'seasoned' 351W with one piston missing upper >ring land ??? > > >Tom Cloud > > > *************************************************************************** * 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: Mazda Ebrahimi Date: Mon, 09 Dec 1996 21:03:31 -0500 Subject: Re: Ford Quad Plug coils Sandy wrote: > > Does anyone have any information on the Quad plug coil assembly on the late > model Ford 4.6's? I have seen them in stangs, and the lincoln. > > Sandy What kind of info are you looking for? ------------------------------ From: Sandy Date: Mon, 09 Dec 1996 22:22:58 -0800 Subject: Re: Ford Quad Plug coils At 09:03 PM 12/9/96 -0500, you wrote: >Sandy wrote: >> >> Does anyone have any information on the Quad plug coil assembly on the late >> model Ford 4.6's? I have seen them in stangs, and the lincoln. >> >> Sandy > >What kind of info are you looking for? > General electrical spec's, are these coils 12 Volts, or are they special for some new style of ford ignition. They looked really small for housing 2 dual coil units... Any info would be great! Sandy ------------------------------ End of DIY_EFI Digest V1 #377 ***************************** 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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