DIY_EFI Digest Tuesday, 5 March 1996 Volume 01 : Number 065 In this issue: Re: Optical Dist sensors Re: Optical Dist sensors [none] Fuel Maps Re: Re: Optical Dist sensors RE: Optical Dist sensors Re: L-jetronic Re: L-jet on an MGB watercooled VW EFI Q's Re: Fuel Maps RE: Optical Dist sensors Re: Optical Dist sensors Re: DIY_EFI Digest V1 #64 Re: Optical Dist sensors Volumetric eff. Re: Volumetric eff. See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: Gerald Luiz Date: Mon, 04 Mar 1996 2:18:15 PST Subject: Re: Optical Dist sensors Actually, the 300ZX don't have a distributor...the disc is attached to the end of a camshaft. I didn't understand the comment about reading the code to determine the cyl #. They have the 360 slots as described. Concentric with those, they have holes every 60 deg., since it runs at cam speed and 6 cyl. These inner slots alternate widths and #1 (0 deg) is different from all the rest. If anyone is interested, I can post the manual page (not that much info except for the picture). Gerald Luiz gluiz@xxx.com ------------------------------ From: "Paul E. Campbell" Date: Mon, 4 Mar 1996 09:46:29 -0500 (EST) Subject: Re: Optical Dist sensors > Actually, the 300ZX don't have a distributor...the disc is attached to > the end of a camshaft. I didn't understand the comment about reading > the code to determine the cyl #. Easy..say you put 3 different optical sensors in. Then put a pattern in front of them that has black and white marks which are the binary codes for the cylinder (000, 001, 010, 011, 100, 101, 110, 111). ------------------------------ From: WERNER_HAUSSMANN@xxx.com Date: Mon, 4 Mar 96 11:35:35 -0700 Subject: [none] Item Subject: cc:Mail Text I have converted a carburetted, 4-cylinder, '75 MGB to Bosch L-Jetronic Fuel Injection. The car works fine and there are no problems with the conversion. The purpose was mostly to see if it could be done, and to improve on the mixture accuracy. No lambda sesor is used. The L-Jetronic uses the trottle position to change the A/F ratio. At about 2/3 full trottle a switch closes and enriches the mixture. Later versions of the Bosch system used manifold vacuum to activate a switch. I want to change my system to this method. I want to enrich the mixture when the manifold vacuum drops. Does anyone have the Bosch number for such a switch? Where can I get one? Or what kind of car has this part so I can get it from a junk yard? Any help is appreciated. Werner ------------------------------ From: Sean McManus Date: Mon, 4 Mar 1996 14:09:06 -0800 (PST) Subject: Fuel Maps My main question here is: How does everyone out there tune the fuel (and ignition) maps on their system? Ultimately, the engine should be put on a dyno and loaded in all sorts of conditions while the exhaust CO, HC, O2 and CO2 is monitored, as well as rpm, torque, manifold pressure, etc. Unfortunately, most of us don't have the funds for this type of testing. The alternate method that seems most feasible is using an on board O2 sensor based A/F meter such as Haltech's or K&N's, tuning the system by driving the car and watching the meter at various conditions. 1) Has anyone had any luck dialing in their system in this manner? 2) Can an O2 sensor based A/F meter be purchased or fabricated for less than the $150-$200 range that I've seen them going for so far? Thanks in advance, Sean McManus University of Washington Formula SAE Yamaha FZR 600 power, modified Haltech F3/Siemens fuel system ------------------------------ From: arthurok@xxx.com (ARTHUR OKUN ) Date: Mon, 4 Mar 1996 14:49:48 -0800 Subject: Re: heres an idea take a gm map sensor and use the signal output 0- 5vdc to drive a schmitt trigger circuit with a variable trip point and settable hysterisis " all it takes is a op amp and a relay". ------------------------------ From: Gerald Luiz Date: Mon, 04 Mar 1996 15:09:33 PST Subject: Re: Optical Dist sensors > > > Actually, the 300ZX don't have a distributor...the disc is attached to > > the end of a camshaft. I didn't understand the comment about reading > > the code to determine the cyl #. > > Easy..say you put 3 different optical sensors in. Then put a pattern in front > of them that has black and white marks which are the binary codes for the > cylinder (000, 001, 010, 011, 100, 101, 110, 111). > Right. I was actaully trying to say that I didn't understand the coding on the Nissan b/c it does not have black/white patterns...just holes/slots. They must detect the width of the pulse (slots different widths) to mark 60/120 etc. I wonder if the end of a slot corresponds to 60 deg or the beginning of a hole. I expect the former. Gerald Luiz gluiz@xxx.com ------------------------------ From: Andrew Dalgleish Date: Tue, 05 Mar 96 10:04:00 S Subject: RE: Optical Dist sensors Generating the pattern is pretty easy with a PC and printer, although the resolution wouldn't be good enough. If you print it out at some huge resolution then reduce it photographically it'd be ok. Any photographer could do it for you. Or print it inverse then just use the film negative. You need at least two sensors anyway (one for cylinder #1 TDC and one for angular resolution), so going to 3 or more isn't going to be much dearer. Using two (or more) "tracks" with quadrature encoding could give you very fine angular resolution. ++++++++++++ --__--__--__ Sensor 1 _--__--__--_ Sensor 2 -_-_-_-_-_-_ Exclusive OR ++++++++++++ ---___---___ Sensor 1 _---___---__ Sensor 2 __---___---_ Sensor 3 -_-_-_-_-_-_ Exclusive OR ++++++++++++ (view this with a fixed-pitch font, eg Courier) Makes me wonder why I piddled around using counter chips all these years. Hmm... time to investigate multiple sensor arrays. I recall seeing a 16-pin DIP with 8 photo-transistors in it years ago. A British magazine had a kit to store programs, etc. on paper. Can anyone help my memory? Regards, Andrew Dalgleish Axon Research, Pty Ltd 6 Wallace Ave, Toorak, VIC 3142 AUSTRALIA Tel +61-3-9826-5538 Fax +61-3-9824-0083 ------------------------------ From: WERNER_HAUSSMANN@xxx.com Date: Mon, 4 Mar 96 16:45:00 -0700 Subject: Re: L-jetronic Item Subject: L-jetronic Hi James I'm new at this list, so I don't know if I should reply to each person, or send my reply to DIY_EFI. I never did see my own message, so I don't know how everyone else saw it. Am I getting other peoples messages? Anyway, James, you're not confused. The my L-Jetronic does have an air meter. It also has a lambda sensor. At 2/3 or more trottle a switch closes, and the lambda sensor circuit is disconnected, the mixture gets richer by about 4% for a little more power and knock protection. Later ( oh.... about '86) the trottle switch was replaced with a vacuum switch to sense the manifold. This way even when the trottle is opened only half way at low rpm, the vacuum drops, the switch closes and the mixture goes rich by ~4%. James, thanks for the offer of the '79 Supra, but no. I have all the parts I need, except this vacuum switch to replace the switch on the trottle shaft. The parts came from a '83 Renault Fuego. Most of the information came from the Bosch FI book ( I don't have the author handy) the the FI book by Hartman. Actual data is very hard to come by. I had no luck getting data from Bosch. If you need specifics I may be able to help. But not much. Werner ______________________________ Forward Header __________________________ Subject: Re: L-jetronic Author: Non-HP-james (james@xxx.ca) at HP-ColSprings,mimegw2 Date: 3/4/96 4:21 PM Werner, I thought that the L-jetronic (1979 and on) used an air flow meter, manifold vacuum to control A/F ratio???? The later LH-jetronic added and oxygen sensor. Am I confused??? Anyway I have a friend with a '79 Toyota Supra that has died at my parents place. I might be able to persuade him to part it out. It has the LH-jetronic and except for a couple of fuel pressure hoses the system works fine. Are you interested at all???? The car has blown a head gasket and thus he's got to tow it away to a wrecker and he'll probably get nothing for it. Sorry Werner I forgot to ask you if your L-type was a speed density system??? Where did you get your parts from for the conversion (ie. what car that is?) Do you have a good reference book that gives physical data on different sensors?? Like resistance of different coolant temp. sensors and whether they change their resistance in a linear, geometric or logarithmic fashion????? Thanks in advance jw ------------------------------ From: WERNER_HAUSSMANN@xxx.com Date: Mon, 4 Mar 96 17:12:43 -0700 Subject: Re: L-jet on an MGB Item Subject: 1.txt "unix headers" Could not convert BINARY FILE item to text. Will attempt to 'shar' item as file '01v3m87' at end of msg. ....................................................................... Item Subject: L-jet on an MGB Hi Andy When I started, I knew nothing. Now that I have done one, it seems very easy. What kind of car do you have. If you have a Renault engine, it should be a piece of cake. The MGB had special problems. It has a siamese intake port (Two intake valves with one intake hole on the head). Worse, the intake stroke for this siamese port is not symetrical. I had intentions of having port injection, but because of the siamese ports with non-symetrical intake stroke I decided to go the trottle body injection route. This is undesirable, and not necessary if you have individual ports per cylinder. The system I used was from a '83 Fuego. I used everything. The complication came two ways. 1. I had to match a trottlle body injector to the system. I used a Ford trottle body with a single Bosch injector. 2. The other trick was the mixture. I wanted to run at a richer mixture than the 'ideal'. Mostly because the manifold was not designed for a lean mixture. To mount the injectors, I suggest you try to get a FI manifold from a car with the same engine but at a later time. Lotus did a lot with Renault engines didn't they? If you have a modified Renault engine (Lotus Europa), check out the Jeff Hartman book 'Fuel Injection; Installation, Performance Tuning, Modification. Anyway mountings are available for injectors, that book gives some examples. Werner ______________________________ Forward Header __________________________________ Subject: Re: L-jet on an MGB Author: Non-HP-ajh (ajh@xxx.edu) at HP-ColSprings,shargw2 Date: 3/4/96 4:18 PM Werner, I'm thinking also of putting FI onto my 70's British car (Lotus). What did you think overall of your project? How did you deal with the intake manifold, esp. with installation of the injectors? Does the range of air and fuel flow rates seem reasonable? Did you acquire your L-jet new or salvaged? thanks, andy # This is a shell archive. Remove anything before this line, # then unpack it by saving it in a file and typing "sh file". # # Wrapped by HP OpenMail user on Mon Mar 4 17:13:13 1996 # # This archive contains: # 01v3m87 # # Error checking via wc(1) will be performed. LANG=""; export LANG PATH=/bin:/usr/bin:$PATH; export PATH rm -f /tmp/uud$$ (echo "begin 666 /tmp/uud$$\n#;VL*n#6%@x\n \nend" | uudecode) >/dev/null 2>&1 if [ X"`cat /tmp/uud$$ 2>&1`" = Xok ] then unpacker=uudecode else echo Compiling unpacker for non-ascii files pwd=`pwd`; cd /tmp cat >unpack$$.c <<'EOF' #include #define C (*p++ - ' ' & 077) main() { int n; char buf[128], *p, a,b; scanf("begin %o ", &n); gets(buf); if (freopen(buf, "w", stdout) == NULL) { perror(buf); exit(1); } while (gets(p=buf) && (n=C)) { while (n>0) { a = C; if (n-- > 0) putchar(a << 2 | (b=C) >> 4); if (n-- > 0) putchar(b << 4 | (a=C) >> 2); if (n-- > 0) putchar(a << 6 | C); } } exit(0); } EOF cc -o unpack$$ unpack$$.c rm unpack$$.c cd $pwd unpacker=/tmp/unpack$$ fi rm -f /tmp/uud$$ echo x - 01v3m87 '[non-ascii]' $unpacker <<'@eof' begin 660 01v3m87 M4F5C96EV960Z(&9R;VT@2YH<"YC;VT^#0I296-E:79E9#H@8GD@9&EA;6]NX M9"YI9&)S=2YE9'4-"@DH,2XS-RXQ,#DN,38O,38N,BD@:60@04$Q-C,W-C$TX M.#D[($UO;BP@xxx.2 M,# Date: Mon, 4 Mar 1996 22:33:33 GMT Subject: watercooled VW EFI Q's Hello fellow listsurfers- I have several variations of the watercooled VW FI systems and I'd love some more info on them... My assortment includes about a dozen systems ranging from '77 Rabbit to '84 Rabbit GTI stuff (a very little Golf also). It appears to me that the earliest systems are completely mechanical... ie air flow meter controls fuel pressure in the loop, excess discarded back to tank. What are the pro & cons of a completely mech. system esp. in a racing app. (racing=Dirt pro-rally, hillclimb (paved & dirt), road race, autox)? Then you've got the electronic version both w/o & w/ O2 sensor & it seems that this is where there are some varying orifice dimensions across models & years, both in throttle body & air flow meter (whats the proper name for this?) How can I choose an optimum induction system diameter after engine mods? Does anyone have a schematic of the guts of the black box - both idle stabilzer and ignition control unit if possible? I know I'm firing off alot of questions, but I guess my general intent is to stir up the VW lurkers! Thanks! and here's my vote for an excellent forum... Regards- Brad Martin '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 '81 VW Scirocco S street car TBD '79 VW Scirocco ice racer ==== Also, you may want to check out: http://www.win.net/bmicad/welcome.html (bmi CAD's homepage) http://www.win.net/bmicad/strahome.html (Stealth Racing's homepage) http://www.win.net/bmicad/nehahome.html (New England Hillclimb Association's homepage) ------------------------------ From: Adam Tate Date: Tue, 05 Mar 1996 11:22:50 +0800 Subject: Re: Fuel Maps At 02:09 PM 4/3/96 -0800, you wrote: >2) Can an O2 sensor based A/F meter be purchased or fabricated for less >than the $150-$200 range that I've seen them going for so far? Here in Australia you can buy this in kit form for $20 from a place called Jaycar electronics. If you check out the DIY fuel injection web site there are also plans there for this type of meter. Adam Tate. [at@xxx.au] http://www.multiline.com.au/~atate/index.html ------------------------------ From: dn Date: Mon, 4 Mar 96 20:54:58 MDT Subject: RE: Optical Dist sensors Andrew Dalgleish writes: > Generating the pattern is pretty easy with a PC and printer, although the > resolution wouldn't be good enough. If you print it out at some huge > resolution then reduce it photographically it'd be ok. Any photographer > could do it for you. Or print it inverse then just use the film negative. I actually did this one time to make my own encoder. I generated the pattern with a CAD program (Generic Cadd), output the file in Postscript, and printed it on the laser printer on clear transparency film. Worked great! The pattern came out crystal clear, I then glued the transparent film onto an aluminum disk and used reflective opto sensors to read it. I ended up using a commercial encoder, however, because the housing was too expensive to machine in quantity. I assume there would be a limit as to how small you could go using this method, but a decent laser printer could make the thing very small with very little loss in image quality. Using a CADD program, you can scale the drawing to any size you want. > You need at least two sensors anyway (one for cylinder #1 TDC and one for > angular resolution), so going to 3 or more isn't going to be much dearer. All you really need is the 2 quadrature tracks, plus a single "index" marker which generates a pulse once per revolution. In this manner, you have a sync pulse which tells you when you have gone one full turn, and simply reference everything to the sync pulse... > Makes me wonder why I piddled around using counter chips all these years. Look into the Hewlett Packard HCTL2016 chip - it has a complete quadrature decoder with digital filtering, and a 16 bit counter readable by any CPU. Works like a damn, and is really easy to use... > Hmm... time to investigate multiple sensor arrays. > I recall seeing a 16-pin DIP with 8 photo-transistors in it years ago. These were used in the ancient but venerable paper tape readers. I doubt if you could still find them, but I think TI used to make some. They still make linear CCD arrays, but these are kind of a pain to interface. You could always use discrete surface mount photo transistors, you can pack them really close together. This is what most optical encoder manufacturers use. Difficult to work with SMD components, though. 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: dn Date: Mon, 4 Mar 96 21:07:37 MDT Subject: Re: Optical Dist sensors Gerald Luiz wrote: > Right. I was actaully trying to say that I didn't understand the coding on > the Nissan b/c it does not have black/white patterns...just holes/slots. > They must detect the width of the pulse (slots different widths) to mark > 60/120 etc. I wonder if the end of a slot corresponds to 60 deg or the > beginning of a hole. I expect the former. Are the slots radial or circular? If they are radial, they may be just positioned every x degrees and give a pulse when they pass by the sensor. If they are circular, it may be that they use a Gray Code scheme, which gives a unique binary position indication for each pattern of holes. With this setup, there would have to be at least 3 sensors, corresponding to 3 sets of semicircular slots. With the radial method, there would only be 1 sensor. In either case, the sensors/light sources would be arranged in pairs, one on each side of the disk, and where there is a hole, the light would shine through and activate the sensor, no hole would block light and the sensor would be off. 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: lowell@xxx.com Date: Mon, 4 Mar 1996 21:23:15 -0800 Subject: Re: DIY_EFI Digest V1 #64 >From: CHAN WEN YEN >Date: Sun, 3 Mar 1996 12:16:27 -0500 >Subject: rough idle -- help > >I'm repairing a 1990 Acura Integra with the 1.8 l engine (no MAF sensor) >. The engine has a rough idle when the ambient air temperature is below >zero and the engine is warm. The idle will dip as low as 500 RPM when the >brake is applied (the car is not automatic) and will eventually settle >just below the normal idle (normal idle - 750). The idle will also >fluctuate +/- 50 RPM @xxx. During periods of rough idling the >vacuum fluctuates rapidly +/- 1/4 inHG about 19 inHG. > > I have changed the air and fuel filters, the spark plugs, the >distributor cap, the PCV valve, reset the base idle & advance, set the >valve lash, removed the carbon from the intake manifold, throttle plate >& valves and used about 4 doses of fuel injector cleaner (motormaster >brand). After changing the air & fuel filters the idle was smooth & >stable for about 5 min. Watch the voltage at the EACV (idle valve) or try pinching the hose to it. If the idle stops bouncing around, it could be sticky, or the ECU is being fooled somehow. Take the valve off and turn the key from off too accessory. It should open fully and close fully when the key is turned off. Things that affect EACV voltage would be: electric load detector, coolant temp sensor, throttle position, rpm, basicaly lots to look at. Try and get a factory shop manual for a good explanation of how it all works. ------------------------------ From: MTaylorfi@xxx.com Date: Tue, 5 Mar 1996 00:37:11 -0500 Subject: Re: Optical Dist sensors Better to use grey code 000, 001, 011, 010, 110, 111, 101, 100. Only one bit is changed at a time. Useful in error checking.... See ya, Mike ------------------------------ From: MTaylorfi@xxx.com Date: Tue, 5 Mar 1996 00:51:03 -0500 Subject: Volumetric eff. I was wondering, does anyone know of a function that roughly follows the V.E. vs. RPM of an engine. Engine size, manifold pressure and intake temperature I'm sure affect V.E., but I'm just looking for a cheap estimate. All you MAP die-hards have made me rethink my already working MAF based EFI system. The $150 MAF sensor is pricey.. See ya and thanks in advanced!! Mike ------------------------------ From: arthurok@xxx.com (ARTHUR OKUN ) Date: Mon, 4 Mar 1996 23:16:52 -0800 Subject: Re: Volumetric eff. thats why many cars dont use a maf or use one of inferior design or quality do you realize how much the customer would pay for a $150 item on a new car i dont think the ones that ford or gm uses cost that much for them to manufacture. ------------------------------ End of DIY_EFI Digest V1 #65 **************************** 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".