DIY_EFI Digest Tuesday, 20 February 1996 Volume 01 : Number 048 In this issue: SAE-reports list Re: your mail Re: Looking for low-cost ignition analysis 'scope Radio Shack DMM with RS-232 interface and ProbeScope Introduction... re: Introduction Re: Introduction... Re: MPX2200 re: Introduction Re: Sequential Setup? Re: MPX2200 Buick DIS coil drivers Re: 286 Vindication Re: Radio Shack DMM with RS-232 interface and ProbeScope Re: Radio Shack DMM with RS-232 interface and ProbeScope Re: Buick DIS coil drivers FW: Buick DIS coil drivers FW: Re: Radio Shack DMM with RS-232 interface and ProbeScope Ford 2.3 litre motor Re: Really awesome TPS... Re: MPX2200 Re: Radio Shack DMM with RS-232 interface and ProbeScope Re: your mail Re: Radio Shack DMM with RS-232 interface and ProbeScope Re: 286 Vindication Re: Sound Blaster as Data Aquisition See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: Tommy.Palm@xxx.se Date: Mon, 19 Feb 96 12:54:23 +0100 Subject: SAE-reports list Here is a list of some SAE-transactions papers that should answer at lea= st half of all questions i've seen in the DIY_EFI group the last months. It was some years ago that believed i was totally alone with the hobby o= f DIY-FI. But my interest bloomed up again when i found the DIY_EFI group = on Internet. Anyhow back then I think I read every SAE- paper from 80-87 (took months= ) and took copies of some of the most usefull for me at that time. Here is the= reports I found most interesting concerning EFI: 851675 Toyota central inj 851674 Fuel atomisation 850044 sect7 Toyota leanburn combustion system (contains info about the = lean burn mix sensor and lean A/F ratio calibration map, comparison between s= eq and simultaneos EFI on torque fluctuation and missfire limit. Helical port v= s straight port on torque. It also has a guide of optimum fuel inj timing = on seq EFI for various speed and load. Very interesting and easy read report! 850074 sect 1 Effects of intake valve closingtimes on combustion. 850293 A new low press single point inj system (Bosch Monotronic). A gui= de for you guys who by some reason want to calculate w/o MAF or MAP. Open or cl= osed loop. 870128 Fuel inj on 4 valve eng. A Nissan report about the problems with transient enrichment and fuellag. Also a good comparisement between diff= erent injection methods on emissions and fueleconomy. Fuel pushback and timing= , uneveness between cylinders etc. Also a must for the serious DIY-EFI'er.= 850293 Sootformation on multipoint fuel inj engine. A very comprehensive= report from GM on the very delicate topic injector aiming. It also tests the ef= fect of sequential injection timing on emmision. In the closing they wrote "...injection targeting is the most significant parameter to reduce smok= e and HC in MPFI engines". Tommy Palm tommy.palm@xxx.se Sweden ------------------------------ From: ehernan3@xxx.com (Edward Hernandez (R)) Date: Mon, 19 Feb 1996 08:05:04 +0500 Subject: Re: your mail "YOW!!! That's a LOT of engine for that car!!!... " reader's reaction to putting a 455 in a Skylark. Skylarks used to come from the factory with 455s, as did Delta 88s, and Firebirds(Pontiac and Olds had their own 455s). The baddest was a 1970 Skylark GS Stage II, if I remember history. No, I'm not that old(born '68) but I am a big fan of sixties muscle, and 1970 was the last hurrah for reckless abandon of cubic inches. The GS Stage II allegedly ran 12s off the showroom floor on street tires. Even if it didn't, it must have been some ride! ------------------------------ From: wmcgonegal@xxx.ca Date: Mon, 19 Feb 96 09:22:27 EST Subject: Re: Looking for low-cost ignition analysis 'scope Just an addition to my prevoius message about the MCSI data aquisition cards. I mentioned that MCSI include with their cards software that can be used by any C or Pascal programmer. The source code for the software provided is written in C, but the cards can easily be programmed in C, Pascal, BASIC, assembler, etc. Will McGonegal Electrical Engineer Mobile Sources Emissions Division Environment Canada wmcgonegal@xxx.ca ------------------------------ From: m_mcdonald@xxx.com Date: Mon, 19 Feb 96 10:14:48 EST Subject: Radio Shack DMM with RS-232 interface and ProbeScope - ------------------------------ > Another possibility: I saw in a Radio Shack (awright, laugh) flyer a few > weeks ago an ad for a DVM with an RS232 interface. I just glanced > at the ad, but for $129 you got the DVM, a 9-pin RS232 cable to connect > to it, and some windows software to go with it. Judging by the picture > in the ad, it looked to be able to display a 'persistent' trace. Heck, > their datastream can't be that tough, write your own display routines if > the supplied software won't do it for you. Instant storage scope. > Anyone know the specs on these DVMs (what the data rate is, how > fast they react to input changes, who really makes them, etc...)?? > Pat Mancuso > - -- > patman@xxx.net -- '64 Nova SS -- Stratham, NH I have one of these digital multimeters (DMM) with an RS-232 interface. Overall, I'm pleased with the unit. As long as you have a VGA or better PC display and DOS or Windows, then whatever appears on the DMM's display appears on the PC's screen in a fancy graphical format. It's fairly easy to write your own software to capture the DMM's output and display it however you want -- graphical or textual. This software is based on BASIC's OPEN COM statement with a baud rate of 1200. The RS-232 interface from the meter delivers between 2 and 3 readings per second. Each reading arrives from the meter as an ASCII character string of 14 bytes. I believe that Metex makes the meters for Radio Shack. Marll McDonald KB1AGM m_mcdonald@xxx.com - ------------------------------ > At 09:05 AM 2/16/96 EST, Lloyd Ferguson wrote: >> I have been milling around an idea of trying a cheap sound-blaster type >> card with an analog input to digitize the signal and then using one of the >> graphical audio editing packages to display it (perhaps doing the whole >> thing on an old 286) any comments? > Sounds interesting. Has any one tried the $99.00 Radio Shack probe scope > with the LCD display and RS232 interface? Sounds too good to be true. I > tried to order one a while ago and was told "It's not available." Sound off > gentlemen! > thanks, > George M. Dailey > gmd@xxx.com Radio Shack's ProbeScope currently (February 19) is not available. It was supposed to be ready on November 30 but had its delivery date changed to January and then to March 31. If this RS item delivers anything near what its description in the current catalog (in the multimeters section) says, then $99 will truly be a bargain price. I'm planning to get one as soon as they're available. Marll McDonald KB1AGM m_mcdonald@xxx.com ------------------------------ From: "Michael C. Truppi" Date: Mon, 19 Feb 1996 11:09:27 -0500 Subject: Introduction... Hello, I would like to take this time to introduce myself. My name is Michael Truppi of Truppi/Kling High Performance. I am involved with some very high HP per inch Fuel Injected motors. I would like to learn more about the late model (94 and on) GM computers. I know they are addressable, but I would like some help getting in. If someone has already done this, I would like to know what to do. I use right know mostly DFI racing computers for my projects, and that adjustability would be nice to have in the stock GM systems. I have several of these computers to work with. I do not know much about the electronics end of things, but I understand how and why racing engines operate. Thanks for listening to my questions. Michael C. Truppi (Mike@xxx.com) http://www.truppi-kling.com Truppi/Kling High Performance inc. 133 RT 22 East Greenbrook NJ 08812 (908) 968 2030 ------------------------------ From: jsturs@xxx.nl (Jim Sturcbecher) Date: Mon, 19 Feb 1996 18:24:26 -0100 Subject: re: Introduction >I would like to take this time to introduce myself. My name is Michael >Truppi of Truppi/Kling High Performance. Welcome Michael, see you found your way from the f-body list to where the real technical discussions take place. Later, Jim Sturcbecher jsturs@xxx.nl ------------------------------ From: Markus Strobl Date: Mon, 19 Feb 1996 13:54:19 -0600 Subject: Re: Introduction... > I would like to take this time to introduce myself. My name is Michael > Truppi of Truppi/Kling High Performance. I am involved with some very high > HP per inch Fuel Injected motors. I would like to learn more about the late > model (94 and on) GM computers. I know they are addressable, but I would > like some help getting in. [snippety snap] Hey Mike, seems we keep bumping into eachother... :-) A good start to getting into the 94+ PCM would probably be to get the rinda diacom package. It's for the PC, and you hook the PC up to the diagnostic connector. The program will show you what's going on in the PCM, although it won't let you change anything. The rinda sw is not availabe for the '96 PCM yet (otherwise I would have bought it). Rinda is at: 800-888-4146 If anyone knows when rinda is going to release it's 96 version, please let me know. Markus Strobl 96 Z28 6M Black/grph. Borla, !CAGS, PEG2, QLC Dallas, Texas 1LE driveshaft, Honker, T-tops, CD, leather F-member 9/93 13.87 @xxx.5mpg @85mph ------------------------------ From: dn Date: Mon, 19 Feb 96 13:37:24 MDT Subject: Re: MPX2200 Cliff Ducharme wrote: > Any more info on the Motorola pressure sensor (price, sources, etc) > would be appreciated. The Motorola sensors should be available at several electronics distributors, Newark Electronics springs to mind. You can reach them at 1-800-4-NEWARK. They didn't show prices in their catalog, but I think they are in the $20 - -$30 range. You can call the Motorola Literature Distribution Center, PO Box 20912, Pheonix, Arizona 85036 and request a Pressure Sensor Databook (free). While you're at it, get a copy of their application note list, it's got a lot of application notes on the HC11, HC05, and HC16 which are very useful. Motorola also has a fax-back service which you can use to get single data sheets and application notes for any of their stuff. Sorry I don't have a phone number for them here, if you want the faxback number let me know, I'll have to get it from work. Newark may also be able to get you a databook, or give you Motorola's phone number. Looking through their catalog, I noticed that the MPX2200 is not available in a differential configuration, and it is a 0-30PSI absolute sensor, which would probably be used in a turbo application... The MPX2100A is a 0-15 PSIA unit which is probably what you want. This sensor is calibrated and temperature compensated and is easy to interface to. There is also the MPX5100 series which have a built in amplifier/signal conditioner which outputs .5 to 4.5 volts, this could be tied directly to your 'HC11 analog inputs with no further ado... This one is available either absolute (MPX5100A) or differential (MPX5100D), 0-15 PSI only, and would be a bit more expensive than the 2100. Both are available in a variety of port styles. Another company which sells similar sensors (almost exactly the same, in fact) is Sensym 1255 Redwood Av. Sunnyvale CA 94089 (408) 744-1500 (old number, may have changed) They will provide a free data book if you give their customer service dept. a call. You probably can't order direct from them, I think they have rather stiff minimum order policies, but they can provide you with the name of a stocking distributor. 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: "Michael C. Truppi" Date: Mon, 19 Feb 1996 16:10:33 -0500 Subject: re: Introduction >Welcome Michael, > >see you found your way from the f-body list to where the real technical >discussions take place. > >Later, > >Jim Sturcbecher >jsturs@xxx.nl Well, I don't know much about the "electronic engineering" portion, but like I said, the engine end I can do. I really need to get into the Late GM boxes. In the end that is what I want to do. Mike ------------------------------ From: Tommy.Palm@xxx.se Date: Mon, 19 Feb 1996 16:14:05 -0500 Subject: Re: Sequential Setup? >Yes I am interested in reading the report. Please post. > It's total of 25 A4 pages and probably rather costly to mail( its my per= sonal money, and there are many people who want's it). Do you have access to a= tecnical library? I e-mailed the numbers of the papers today in the DIY_= efi group. Whats your project? Tommy tommy.palm@xxx.se Sweden ------------------------------ From: Grant Beattie Date: Mon, 19 Feb 1996 14:09:10 -0700 (MST) Subject: Re: MPX2200 On Sun, 18 Feb 1996, CF Ducharme wrote: > Yes there are (at least) two of us - Jim Staff doing a high mileage vehicle > application with a B&S, and me doing a senior (43 year old senior?) design > project for my BSEE. I believe Jim is using an Intel 286, and I'm using a > Motorola M68HC11 (Coactive Aesthetics GCB11) and after graduation, if I'm > bored I may try to port it to my '85 Electraglide - but, as they say, 'Things > are different on a Harley...' I will probably post some of my project details > to the DIY_EFI home page once things draw near a close. There is a potential market for anyone that can come up with a small efficient EFI for B&S 5 hp motors.... Kart racing. There are piles of B&S 5hp motors (using methanol and other mods to make them viable) on the Kart racing tracks in N. America. I'm talking about 100kph racing here, not kiddie fun karts, but there may be a market there too! GB ------------------------------ From: John S Gwynne Date: Mon, 19 Feb 96 17:35:36 -0500 Subject: Buick DIS coil drivers - -------- I made some current and voltage measurements on a Buick 3.1L V6 with a distributor-less ignition system this past weekend. Three coils mounted on what appeared to be the driver module. The coil's waveform on the primary looked really good. Does anyone know how to drive these modules? Is there an 8 cylinders version? (use 2 4-cyl versions?) John S Gwynne Gwynne.1@xxx.edu _______________________________________________________________________________ T h e O h i o - S t a t e U n i v e r s i t y ElectroScience Laboratory, 1320 Kinnear Road, Columbus, Ohio 43212, USA Telephone: (614) 292-7981 * Fax: (614) 292-7297 - ------------------------------------------------------------------------------- ------------------------------ From: Bruce Bowling Date: Mon, 19 Feb 1996 18:52:13 EST Subject: Re: 286 Vindication ~ >Warning; is it a MPX2200DP? It reads differential pressures. You need absolute ~ >pressure. I had to use the MPX200AP thats absolute w/o temp compensation. Since ~ >Motorola did'nt have any compensated one year ago. I use turbo press up to 1,5 ~ >bar but when calibrating the MPX200 it streched it's linear area 1 bar over the ~ >specified so it's still useable. The temp comp wont be any big problem i think. ~ >When i calculated on it it follows the compensation for airtemp vs density that ~ >you anyhow must do in your software (or maby in hardware is possible to of ~ >course), so its near to automatic, but maby a bit slow! That is if you apply ~ >inucted airtemp to the MAP sensor of course (how that is done???). Tell me how ~ >you intend to dampen the MAP signal? Mecanical or electronical, thats one of my ~ >problems. ~ > ~ >Keep up good work, please tell me if its a new AP on the market! ~ > ~ >Tommy Palm ~ >tommy.palm@xxx.se ~ >Sweden ~ >> ~ >> ~ > ~ If you are not going up and down mountains all day a differential sensor ~ will work fine. ~ regards, ~ I may not be absolutely correct on this, but I was under the impression that you need *both* absolute and differential, to get a linear form Y = A + B*X, so one knows the slope as well as the offset. With two absolute pressure sensors, one can obtain the above form, because both sensors are referenced to an absolute pressure (thus yielding A), and the difference will yield B, If one uses only one absolute sensor, then one can take a reading when the engine is off (like when the key is on run but not yet to start) and save this as atmospheric pressure. Then when the car is running, the second reading yields the same info as with two sensors. That is if the atmospheric pressure remains constant. (I know Electromotive uses the one sensor method). With only a differential sensor, you can never reference this against any absolute values. This may be O.K., but how then does one implement, for example, a timing advance lookup table with absolute vacuum as one of the inputs? I guess one can come up with an absolute pressure value and always use this with the differential sensor. But this may work only if you do not go up an mountain, and if the barometric pressure remains the same forever. BTW, my environmental correction WWW page shows the effects of altitude and barometer on engine HP/torque, and they can be dramatic. - - Bruce - -- - ----------------------------------------------------- <<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> - ----------------------------------------------------- Bruce A. Bowling Staff Scientist - Instrumentation and Controls The Continuous Electron Beam Accelerator Facility 12000 Jefferson Ave - Newport News, VA 23602 (804) 249-7240 bowling@xxx.gov http://devserve.cebaf.gov/~bowling - ----------------------------------------------------- <<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> - ----------------------------------------------------- ------------------------------ From: "George M. Dailey" Date: Mon, 19 Feb 1996 17:45:32 -0600 Subject: Re: Radio Shack DMM with RS-232 interface and ProbeScope I'm not a pro "hardware hacker" but, with a very fast PIC and an even faster A/D converter, could an anolog to RS232 module be built? Are there single chip devices out there, that will read an anolog voltage and transmit it at a high baud rate via RS232? I think the bottleneck would be the RS232 link. I can see a PIC-A/D reading the voltage in real time but not being able to 'talk' fast enough. What do you seasoned hackers think? GMD ------------------------------ From: robert dingli Date: Tue, 20 Feb 1996 11:24:31 +1100 (EST) Subject: Re: Radio Shack DMM with RS-232 interface and ProbeScope > > I'm not a pro "hardware hacker" but, with a very fast PIC and an even faster > A/D converter, could an anolog to RS232 module be built? Are there single > chip devices out there, that will read an anolog voltage and transmit it at > a high baud rate via RS232? > I think the bottleneck would be the RS232 link. I can see a PIC-A/D reading > the voltage in real time but not being able to 'talk' fast enough. What do > you seasoned hackers think? How about using the joystick input through the games port? We have used it a few times for basic PC inputs, digital and analogue. Robert - -- Robert Dingli r.dingli@xxx.au Power and Control Systems (+613) 9344 7966 Thermodynamics Research Labs (+613) 9344 7712 University of Melbourne, AUSTRALIA ** he who dies with the most toys, wins ** ------------------------------ From: arthurok@xxx.com (ARTHUR OKUN ) Date: Mon, 19 Feb 1996 17:00:19 -0800 Subject: Re: Buick DIS coil drivers their not that difficult to work with the crank shaft sensor hooks directly to the module below 400 rpm the module directly controls the spark for starting ; their are 8 cyl units availible the module is expensive about $150 as a replacement part minus coils ------------------------------ From: jac@xxx.us (john carroll) Date: Mon, 19 Feb 96 17:54:52 PST Subject: FW: Buick DIS coil drivers I have been using these modules on aircraft engines for several years. They are very easy to adapt to any thing. You can even use one lead from one coil and run a single cylinder engine. The best description I have found is from several pages in a GM training manual, publication 16009.10-1. Mine is dated 1986. The operation of a number of other peripherals is covered as well as wiring diagrams and signal descriptions. The coil base is controlled by several signals and emits a 6 pulse per revolution tachometer signal. Timing comes from a notched disk that stimulates a cheap ($20) probe to produce a positive then negitive pulse at six symetrical locations pluss one additional, oddly spaced notch to track tdc/tbc of cyl #1. If the signals from the controller are not acceptable, the device runs in limping mode that limits advance to about 10 degrees at 3000 rpm. As a magneto replacement on aircraft we sometimes use the thing in this mode for ever by dumping in 15 degrees of fixed advance and letting the thing come up 10 degrees on its own. In this mode the thing only needs power and a signal from the crank sensor to function. The other signals used to control operation are BYPASS which tells the coil base to run on its own and an EST signal which I believe works like other GM EST signals. These two signals are generated by the controller. The coil base generates REF, a phase signal that indicates 60deg btdc. Five volt CMOS signals control the device well. TTL is a bit iffy. If you want to distinguish between cylinders you will have to look at the cam with another sensor. I use a GM MAP sensor and calculate and control advance with a Phillips/Signetics 87c550. I dump a continuous string of serial data to an RS232 port and update an 80 character LCD device using about 25 percent of the controller resource at 3000 rpm I could probably be persuaded to peddle some timing disks and copy some pages if people really need them for real projects. - -------------------------------------------------------------------------- john carroll jac@xxx.us >-------- > > I made some current and voltage measurements on a Buick 3.1L V6 >with a distributor-less ignition system this past weekend. >Three coils mounted on what appeared to be the driver module. > >The coil's waveform on the primary looked really good. Does anyone know >how to drive these modules? Is there an 8 cylinders >version? (use 2 4-cyl versions?) > > John S Gwynne > Gwynne.1@xxx.edu >___________________________________________________________________ ____________ > T h e O h i o - S t a t e U n i v e r s i t y > ElectroScience Laboratory, 1320 Kinnear Road, Columbus, Ohio 43212, USA > Telephone: (614) 292-7981 * Fax: (614) 292-7297 >------------------------------------------------------------------------------- > > ------------------------------ From: jac@xxx.us (john carroll) Date: Mon, 19 Feb 96 18:25:23 PST Subject: FW: Re: Radio Shack DMM with RS-232 interface and ProbeScope I am finishing a PIC project that communicates in 8 bit bytes +1 +1 at about 80k baud without really trying for maximum speed. The chrystal speed could be increased from 4 to 20 Mhz. If the PIC has the data ready it can be sent in a hurry. What are you doing with all this fast data? - ------------------------------------------------ john carroll jac@xxx.us >I'm not a pro "hardware hacker" but, with a very fast PIC and an even faster >A/D converter, could an anolog to RS232 module be built? Are there single >chip devices out there, that will read an anolog voltage and transmit it at >a high baud rate via RS232? >I think the bottleneck would be the RS232 link. I can see a PIC-A/D reading >the voltage in real time but not being able to 'talk' fast enough. What do >you seasoned hackers think? > >GMD > ------------------------------ From: Bill Date: Mon, 19 Feb 1996 21:03:34 -0800 Subject: Ford 2.3 litre motor Some time ago, I salvaged a 2.3 litre turbocharged motor from an '87 T-Bird. Although I have everything (ECU, EGO, MAF, etc.), most of the wiring was cut to facilitate removal of the equipment from the body. Does anyone have, or know where to find a pin-for-pin wiring diagram for this equipment? Any help would be greatly appreciated. Thanks, Bill Sarkozy Kalamazoo, MI ------------------------------ From: Donald Whisnant Date: Mon, 19 Feb 1996 21:41:51 -0500 Subject: Re: Really awesome TPS... Timothy Coste wrote: > I'm not sure if these are exactly what you're talking about, but >from a C&H Sales Company (surplus and misc sales) catalog... > > Bearing Module #blah This unit contains...the following: > one resolver #CSHblah, one resolver #CVHblah, one differential, > one motor tachometer...and many high precision and anti-backlash > gears, precision bearings, standoffs, etc. Dim.... Price: $15 US. > > Obviously (I think) a mil. spec. fire control or such unit. They >also have a Range Module with similar stuff. If these are what you >speak of, and if they are durable enough to most likely still be >in good shape, it may be a way to try your idea on the cheap. > > Your post jogged a little something loose in my brain (as if I >can spare any little things being jarred from my brain) and I >remembered reading about these things in this catalog and wondering >what the heck they were (and might be good for). In the true >spirit of diy, I really get into surplus catalogs. > > Just FIY... > > Tim Coste > tlcoste@xxx.edu > :) .. This sounds similar to what I was talking about. I presently don't have a surplus catalog from them (and yes I get into surplus cats too!) so I can't look it up and see... ... Resolvers are really very simple devices with the price reflecting the accuracy with which they were wound. ... Basically they are two windings (well, actually three windings) and are set up kinda like a motor. The "primary" winding is excited by the driver/receiver circuit to a known frequency AND phasing. As the device's shaft rotates, the coupling between the "primary" and "secondary" vary by the sine/cosine of the angle of incidence. The driver/receiver circuit decodes this and outputs a voltage proportional to angular movement. Another neat device to play with is a Synchro (basically a resolver with only one output set -- instead of sine and cosine). You can actually hook two synchros together and the movement performed on one will be replicated on the other (i.e. synchro movement)... This is very neat to play with in things like model planes, etc... Also (in addition to the resolver) you will need the driver/receiver circuit. Analog Devices makes several of these -- some even with digital outputs to hook directly to a cpu... However, most of the Analog Devices chips are expensive (especially the mil spec ones). I think they are in the Data Converter Reference Manuals (there are 2 of them) and the Military/ Aerospace Reference Manual. Someone on this forum (I don't remember who) mentioned an LVDT (Linear Variable Differential Transformer) -- Those are basically a resolver that is stretched out over a linear distance (actually they work by voltage coupling coming out of one winding pair and going into another) ... Those would work equally as well EXCEPT you have to convert radial motion into linear motion -- where as the resolver is already radial... ... As far as experimenting with these things, we have all 3 of these (resolvers, synchros, and lvdts) where I work .... I've just never tried putting them on as a TPS... ... For sources, since the accuracy of a tps doesn't need to be that of a missile guidance system, surplus markets would be good -- but possibly have slightly flawed windings ... For those of you seeking missile quality units, check the Thomas Register -- I know of a pretty good place in Charleston, SC that makes them for mil applications... Donald Whisnant dewhisna@xxx.com ------------------------------ From: Angus Mackinnon Date: Tue, 20 Feb 1996 14:24:21 +1100 (GMT+11:00) Subject: Re: MPX2200 > [snip] dn wrote: > -$30 range. You can call the Motorola Literature Distribution Center, > PO Box 20912, Pheonix, Arizona 85036 and request a Pressure Sensor Databook > (free). While you're at it, get a copy of their application note list, The pressure sensor databook has application notes for the sensors. > Looking through their catalog, I noticed that the MPX2200 is not available > in a differential configuration, and it is a 0-30PSI absolute sensor, > which would probably be used in a turbo application... The MPX2100A is I have used the MPX2200 in a data logger for a turbo engine. I used the simplest instrument amplifier circuit from the application notes, uses a LM 358N dual op amp and a few other discrete components. The circuit gives a reasonable voltage gain and swing and hooks up to an A/D converter. The results I got seemed to be ok. I used oversampling and a moving average filter for each data point. In regard to the issue of dampening vacuum fluctuations in the inlet manifold, I read that some of the smaller Japanese (Daihatsu) turbo cars use in-line dampeners to smooth out fluctuations in the factory boost guages. Maybe one of these could be used in the B&S lawnmower system? Angus. - --- Angus Mackinnon Dept of Digital Systems angus@xxx.au Monash University, Clayton phone: +61 3 9905 3403 Victoria, AUSTRALIA ------------------------------ From: "Andrew Dennison" Date: Tue, 20 Feb 1996 14:39:36 +1000 Subject: Re: Radio Shack DMM with RS-232 interface and ProbeScope On 19 Feb 96 at 17:45, George M. Dailey wrote: > I'm not a pro "hardware hacker" but, with a very fast PIC and an > even faster A/D converter, could an anolog to RS232 module be > built? Get a parallel output A/D and drop it on the printer port - there is a parallel port FAQ somewhere that would tell you how to drive the port in software. Unfortunately I have access to a Fluke scopemeter (which gives great waveforms on injector signals, coil primaries, etc.) so I don't need to rig up one of these PC scopes! ps. I think one of the Aussie Elecrtonics magszines (Silicon Chip or Electronics Australia) had a project to build a device like this a few years ago for around $60AUS ------------------------------ From: Corey Cole Date: Mon, 19 Feb 1996 21:40:17 -0700 (MST) Subject: Re: your mail On Mon, 19 Feb 1996, Edward Hernandez wrote: > "YOW!!! That's a LOT of engine for that car!!!... " reader's reaction > to putting a 455 in a Skylark. > > Skylarks used to come from the factory with 455s, as did Delta 88s, > and Firebirds(Pontiac and Olds had their own 455s). The baddest was a > 1970 Skylark GS Stage II, if I remember history. No, I'm not that > old(born '68) but I am a big fan of sixties muscle, and 1970 was the > last hurrah for reckless abandon of cubic inches. The GS Stage II > allegedly ran 12s off the showroom floor on street tires. Even if it > didn't, it must have been some ride! > The Stage 2 spec 455 is what I'm looking at putting into the old beast. The best motor for the year chassis I have was a boat anchor 401 ( I shouldn't dog it, but it's just too heavy) I'd like to see decent mileage and drivability (like decent mileage is possible with 400+ hp and 455 cu. in.) As far as running 12s, I'd believe it. The Stage 1s ran 13's - 14's at 4000-4200 lbs. Corey Cole colec@xxx.edu '65 Skylark "Knowledge is power...but cubic inches help." Go #24!!!!! I was drunk the day my mom got out of prison and I went to pick her up in the rain. But before I could get to the station in my pick up truck, she got runned over by the darned old train... David Allen Coe Steve Goodman ------------------------------ From: Brad Martin Date: Mon, 19 Feb 1996 23:39:48 -0500 Subject: Re: Radio Shack DMM with RS-232 interface and ProbeScope At 11:24 AM 2/20/96 +1100, you wrote: >> >> I'm not a pro "hardware hacker" but Me either, but... >> A/D converter, could an anolog to RS232 module be built? Are there single >> chip devices out there, that will read an anolog voltage and transmit it at >> a high baud rate via RS232? I think that National Semiconductor makes a variety of single chips that are exactly what you are looking for... maybe a ADC12130Cxxxx Check out the NS homepage at: http://webdirect.natsemi.com or maybe the Digikey page: http://www.digikey.com ===== Also, you may want to check out: http://www.win.net/bmicad/welcome.html http://www.win.net/bmicad/strahome.html http://www.win.net/bmicad/nehahome.html http://www.win.net/bmicad/icetrial.html - -The Hacker '92 Subaru SVX '84 VW Rabbit GTI ex-PRO Rally car, now all 'round racer/beater '83 VW Rabbit GTI PRO Rally Car wannabe - hillclimbs too '79 VW Scirocco ice racer ------------------------------ From: Mark Boxsell Date: Tue, 20 Feb 96 19:29:28 +1100 (EST) Subject: Re: 286 Vindication At 06:52 PM 19/02/96 EST, you wrote: >I may not be absolutely correct on this, but I was under the impression that >you need *both* absolute and differential, to get a linear form Y = A + B*X, >so one knows the slope as well as the offset. With two absolute pressure sensors, >one can obtain the above form, because both sensors are referenced to an >absolute pressure (thus yielding A), and the difference will yield B, >If one uses only one absolute sensor, then one can take a reading when >the engine is off (like when the key is on run but not yet to start) and >save this as atmospheric pressure. Then when the car is running, the second reading >yields the same info as with two sensors. That is if the atmospheric >pressure remains constant. (I know Electromotive uses the one sensor method). > That's what people do however you have to stop the engine and restart it at the top of the mountain before it corrects! Two sensors is the best method. Two absolute or one absolute and one differential is does not matter. (If you want to change altitude). >With only a differential sensor, you can never reference this against >any absolute values. This may be O.K., but how then does one >implement, for example, a timing advance lookup table with absolute >vacuum as one of the inputs? > You are referencing it against barometric and if it does not change what's the difference! You can calculate a correction by picking any point on the line, the issue is that it remains by definition a constant. >I guess one can come up with an absolute pressure value and always >use this with the differential sensor. But this may work only if >you do not go up an mountain, and if the barometric pressure remains >the same forever. This is my point. Pressure change due to weather has no effect (because they are so small) as far as the engine is concerned so if you don't change your altitude no problem. > >BTW, my environmental correction WWW page shows the effects >of altitude and barometer on engine HP/torque, and they can be dramatic. Yes, they sure can. My final point, if the pressure does not change then you don't have to correct for it. ie. there is nothing to correct. > >- Bruce > >-- >----------------------------------------------------- ><<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >----------------------------------------------------- > Bruce A. Bowling > Staff Scientist - Instrumentation and Controls > The Continuous Electron Beam Accelerator Facility > 12000 Jefferson Ave - Newport News, VA 23602 > (804) 249-7240 > bowling@xxx.gov > http://devserve.cebaf.gov/~bowling >----------------------------------------------------- ><<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >----------------------------------------------------- > regards, Mark Boxsell MRB Design. ------------------------------ From: rpratt@xxx.au (Rodney Pratt) Date: Tue, 20 Feb 1996 10:52:48 GMT Subject: Re: Sound Blaster as Data Aquisition On Mon, 19 Feb 1996 18:50:21 +1100, you wrote: >> run the dc thru a voltage to frequency convertor first, then digitize with >> the sound blaster. >> you could then save the result as a wave file (am assuming PC with windows >> vs. eg mac) >> the format of a wave file is probably on the internet "somewhere" and >> "somewhere" on my hard >> disk is a MATLAB file that can read it as an array of numbers that can be >> FFTed, graphed, displayed >> or whatever. (or run the pitch thru a lookup table to reverse the v2f >> converter.) >> Matt Smith >> masmith089@xxx.com >> Mailer Eudora 1.5.2 > >What kind of accuracy can you get (do you expect) from such a system ?? > >I would think it would not be as good as direct DC sampling. >Any comments from anyone who has tried ??? > > >-- I know of someone who has used this approach successfully on a Kart to log RPM. They used a portable tape recorder to record the output of a magnetic pickup (directly in the microphone input) mounted to detect RPM from a geared drive wheel. They then played this back into a Soundblaster and wrote some software to analyse the .WAV file and count zero-crossings, and hence producing a plot of RPM vs time. The magnetic pickup is perfect for this application as it produces a nice sine wave output (ie no DC). It may also be suitable for other frequency output type devices (ie. MAF sensors). A cheap data logging alternative!!!!!! Cheers, Rodney Pratt rpratt@xxx.au ------------------------------ End of DIY_EFI Digest V1 #48 **************************** 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".