DIY_EFI Digest Wednesday, March 8 2000 Volume 05 : Number 092 In this issue: Re: O2 sensor Voltage Re: O2 sensor Voltage Electronic Transmission Control Re: AFM measurement/backpressure (was Turbo speed sensor) Re: Electronic Transmission Control Re: AFM measurement/backpressure (was Turbo speed sensor) Re: AFM measurement/backpressure (was Turbo speed sensor) Re: AFM measurement/backpressure (was Turbo speed sensor) Re: O2 sensor Voltage Re: Electronic Transmission Control Re: Electronic Transmission Control Re: O2 sensor Voltage Re: AFM measurement/backpressure (was Turbo speed sensor) Re: Any electronically controllable gas regulators ? Re: AFM measurement/backpressure (was Turbo speed sensor) Re: Electronic Transmission Control Re: Electronic Transmission Control Re: Electronic Transmission Control Re: Electronic Transmission Control Re: Electronic Transmission Control Re: Electronic Transmission Control Re: Electronic Transmission Control RE: Electronic Transmission Control See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Wed, 8 Mar 2000 08:57:18 -0700 From: "Chad Beauregard" Subject: Re: O2 sensor Voltage >"Steve Leonard" asked: > >> I need to alter the voltage signal coming from a O2 sensor. I want >to fool the ECU into a leaner condition. >> I am going to school, driving 110mi round trip. I want to see how >much fuel mileage I can sqeeze out of my Geo Metro. Where can I get plans >for a simple voltage "stepper". > >Uh, what's a 'Voltage "stepper"'? > >A simple single-supply operational amplifier could add an offset Voltage to >the EGO Voltage, or could effect the EGO Voltage by a ratio. "How lean can >you go", we wonder? > >Mike "How lean can you go" is a good question. Keep in mind that the leaner you run an engine, the hotter it runs. This could present a few other problems that would make the mile or two extra mileage not worthwhile. I'm working on a similar project, only I want to be able to fool the O2 sensor in either direction (rich or lean). I'll be using a microprocessor to control the O2 sensor line to the ECU, and I'd like to be able to set the conditions for rich, lean, and optimal mixture. In my case, the ECU really only pays attention to the O2 sensor signal from idle to about 3000 RPM, depending on the throttle position. I want to be able to fool the ECU into thinking that the mixture is optimal during these conditions while I mess around with the pulse width being delivered to the injectors. My first idea is to use an A/D to monitor the input voltage, modify it to optimal, and then a D/A to tell the ECU not to change the fuel. Any other ideas or extra input would be appreciated. Chad - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 11:20:00 -0500 From: "nacelp" Subject: Re: O2 sensor Voltage Might not be anywhere near that easy depending on your ecm. Have you read about any of the ecm strategies for monitoring O2 v, and corrections?. Some expect a specific response, and time delay from the O2 to changes in injector timing. Grumpy > I'm working on a similar project, only I want to be able to fool the O2 > sensor in either direction (rich or lean). I'll be using a microprocessor > to control the O2 sensor line to the ECU, and I'd like to be able to set the > conditions for rich, lean, and optimal mixture. In my case, the ECU really > only pays attention to the O2 sensor signal from idle to about 3000 RPM, > depending on the throttle position. I want to be able to fool the ECU into > thinking that the mixture is optimal during these conditions while I mess > around with the pulse width being delivered to the injectors. My first idea > is to use an A/D to monitor the input voltage, modify it to optimal, and > then a D/A to tell the ECU not to change the fuel. Any other ideas or extra > input would be appreciated. > > Chad > > -------------------------------------------------------------------------- - -- > To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) > in the body of a message (not the subject) to majordomo@xxx.org > - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 11:24:40 -0500 From: "Gwyn Reedy" Subject: Electronic Transmission Control I've picked up a good 4L80E transmission out of a '94 pickup for use in a project that won't have EFI. Aftermarket vendors want from $900 to $2000 for a computer to control the transmission. Way too much. What would it take to make the EMC out of a similar vehicle and get it to ignore all but TPS and VSS so it can control the transmission? Any other suggestions? Gwyn Reedy Brandon, Florida mailto:mgr@xxx.com - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 11:37:08 -0500 From: "nacelp" Subject: Re: AFM measurement/backpressure (was Turbo speed sensor) > The condition which is being avoided is that of knock. A knock > sensor is apparently out of the question to aid in learning the > engine's response under a range of conditions. If your only talking aout one of the acoustic trash sensors. Try working out an ionization type, and I'd bet your "idea" would change. It is theoretically > possible that a single knock event can destroy a fragile engine. ??, where did you hear that?. That is in the realm of not knowing what your doing, tune up wise. Theory based on what? > However, you don't need to run the engine to severe knock > conditions, and once you've learnt the response, you can use that to > avoid the knock condition by a safe, but minimal margin. Sounds like your of the school, of as much timing as possible, rather then then as little timing as consistent with max HP. The difference is what lets engine win races, or live on the street. he speed of > deflection of the crankshaft - the knock pressure will cause the > angular velocity to exhibit a characteristic "jitter". You won't be > able to measure that easily at the flywheel end - the inertia will > "squelch" the jitter, but a measurement at the other end could be > worthwhile if there are no inertial loads there. Oh, well then the gm strategy of measuring accleration rates doesn't work??. sensor if the resolution were high enough. > Of course, that's an empirical approach... > The exhaust backpressure determines the internal exhaust gas > recirculation and hence the remaining displacement to be filled with > fresh mixture. That's the air-fuel ratio - remembering that the two > differ by about 400C (if not more) in temperature, making for a more > volatile mixture (hence the need to retard with more EGR). Retard with EGR??. It's inert as far as combustion goes. The delution, on higher rpms is being way over stated, or overthought here in my book. The is a huge column of gas drawing across the exhust as it opens, and draws more raw fuel into the exhuast, then there is EGR at higher rpms. At cruise, yes there is some, and at idle lots of self egring, but niether are boost conditions. > If there's an exhaust valve overlap with inlet, and we don't know > the exhaust backpressure, then we must measure if the overlap causes > exhaust to be drawn back into the cylinder, or if a significant > portion of the fresh mixture is being "scavenged" into the exhaust. > Enter your trusty O2 sensor. You need it to react fast enough to > detect a rise in O2 after the exhaust valve to indicate scavenging, > or to remain "level" indicating only exhaust gases downstream of the > exhaust valve (obtaining such a sensor's a problem for higher engine > speeds). Nope, just tune for best performance. Your acting like electronics is the end all to performance, and ignoring tuning. There is nothing truly trusty about O2 sensors, they degrade with use, are affected, by temp, fuel, and back pressure. So you need to worry about those considerations then also. We can still calculate the AFR based on our knowledge of > volumetric efficiency of the engine. > Prior testing with the engine will indicate appropriate ignition > timing to avoid knock at a particular AFR for a specific load/boost. Which again accounts for the backpressure (or lack of it) issue. Grumpy ix.com.au > http://www.perth.dialix.com.au/~bernie - Private HP > -------------------------------------------------------------------------- - -- > To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) > in the body of a message (not the subject) to majordomo@xxx.org > - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 11:43:01 -0500 From: "nacelp" Subject: Re: Electronic Transmission Control Ahh, way too much work, I'll gladly take it off your hands for shipping . Since, I doubt you'll do that, you might just look at a diesel pickups pcm, and see what it needs. Might consider that the dumber the controller the harder the shifts. Or tranny life becomes an issue, since you'll need to have high line pressure shifting for it to live at WOT shifting. Just thinking out loud Grumpy > I've picked up a good 4L80E transmission out of a '94 pickup for use in a > project that won't have EFI. Aftermarket vendors want from $900 to $2000 for > a computer to control the transmission. Way too much. > > What would it take to make the EMC out of a similar vehicle and get it to > ignore all but TPS and VSS so it can control the transmission? > > Any other suggestions? > > Gwyn Reedy > Brandon, Florida > mailto:mgr@xxx.com > > -------------------------------------------------------------------------- - -- > To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) > in the body of a message (not the subject) to majordomo@xxx.org > - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Thu, 09 Mar 2000 01:03:29 From: "Mike (Perth, Western Australia)" Subject: Re: AFM measurement/backpressure (was Turbo speed sensor) At 12:01 AM 9/03/2000 +0800, you wrote: >>I suppose in those conditions a simple pressure sensor off the exhaust >>before the turbo would be OK. > >>ie Short (cooled) piece of pipe to carefully mounted sensor. > >Most pressure sensors will handle only about 180C. Oh yes - have one of those Motorola silicon bridge units, max is about 75deg C > Cooling the pipe >reduces the pressure as far as I know; you need to know the amount >of cooling (temperature sensors?) to determine the actual >backpressure. Doubt it - flow is effectively zero and the sensor need only be about 300mm from the exhaust and behind the heat shield. I'm not thinking of using any forced cooling normal convective is fine. Once its in steady state the pressure at the sensor will follow the point at which the pipe enters the exh manfiold (I would exspect) quite quickly, actually 200mm behind heat shield would make it OK (torch into garage at 1am, trip over bin I left there - ouch), >That's a bit more number crunching than you might want to do. Even >then, the pressure you determine will be the pressure at some time >in the past - that might be as long as 10 milliseconds ago. You >almost certainly will not see the pulsations resulting from the >opening and closing of valves. Not interested in pulsations (at moment) but the average pressure over a exhaust cycle (though any pulsations could be interesting, though I'm not sure of the b/w of the sensor, but IIRC its better then 1mS), I'd be plumbing the pipe into a point just before the turbo flange and the length of pipe to the sensor may very well dampen any fluctuations well major peaks anyway. >>The speed wouldn't be much of an issue for this reason. Once its installed >>and calibrated then the conditions which lead to a immediate ignition >>retard can be 'pre-emptive' ie. a differentiator off the pressure sensor >>could initiate an interrupt for immediate retard by a set number of >>degrees - or even better, the differentiator sets the interrupt pulse >>width depending on rate of 'upward' change of pressure in exh before turbo. > >The condition which is being avoided is that of knock. A knock >sensor is apparently out of the question to aid in learning the >engine's response under a range of conditions. It is theoretically >possible that a single knock event can destroy a fragile engine. >However, you don't need to run the engine to severe knock >conditions, and once you've learnt the response, you can use that to >avoid the knock condition by a safe, but minimal margin. Yeah sure, but you can see that a 'pattern' of AFM, speed, advance, exh pressure - could be recognised as one which leads to knock as learned from previous cycles. Hence when this 'pattern' or a probabilisitc part of it appears then the level of advance is reduced - the greatest weighting factor would likely be combination of load and exhast backpressure, in that case a 10mS response time would be adequate (quick mental calc) but I expect it to be as good as 1mS. >An alternative may be to build pressure sensors into the head of the >engine; those devices must exist (presumably you could buy them if >you had the money). Another option may be to monitor the speed of >deflection of the crankshaft - the knock pressure will cause the >angular velocity to exhibit a characteristic "jitter". You won't be >able to measure that easily at the flywheel end - the inertia will >"squelch" the jitter, but a measurement at the other end could be >worthwhile if there are no inertial loads there. >A PLL-type logic could be used to detect the jitter from a >"crank-angle" sensor if the resolution were high enough. > >Of course, that's an empirical approach... mmmm seems a bit complex when it should be fairly predicatable for a given engine when the bulk of knock inducing parameters are known in advance, unless its a test engine with frequent alterations, >The exhaust backpressure determines the internal exhaust gas >recirculation and hence the remaining displacement to be filled with >fresh mixture. That's the air-fuel ratio - remembering that the two >differ by about 400C (if not more) in temperature, making for a more >volatile mixture (hence the need to retard with more EGR). > >At high speed, we can consider the two gas mixtures to be >stratified; they won't change significantly in volume, nor will they >mix to a significant degree. mmm With you so far, >We can measure "exactly" how much fresh mixture enters the cylinder >by measuring the flow through the inlet tract, but only if the >exhaust valve has already closed. What we need for that is a >high-speed differential pressure sensor and two pressure taps ahead >of the inlet valve. The inlet temperature is fairly constant and we >should already know what this is for calculating the amount of fuel >to inject... mmm But surely the AFM - even a slow one will point to the overall flow, cycle to cycle variations are interesting but I can't see how its information value is of immediate use given the engines unlikely to have instantaneous speed changes - hence we can use the s/w to pre-empt the knock condition. Don't get me wrong, its an interesting proposition but, I seem to have got myself fixated on the pattern matching pre-emptive value in AFM, speed, advance, exh pressure etc. Especially as I hope to push my own setup a bit higher and not having a lot of engine instrumentation has me at a loss - exhast backpressure sounds like a useful qty to know - at least for experience - that and EGT. >If there's an exhaust valve overlap with inlet, and we don't know >the exhaust backpressure, then we must measure if the overlap causes >exhaust to be drawn back into the cylinder, or if a significant >portion of the fresh mixture is being "scavenged" into the exhaust. >Enter your trusty O2 sensor. You need it to react fast enough to >detect a rise in O2 after the exhaust valve to indicate scavenging, >or to remain "level" indicating only exhaust gases downstream of the >exhaust valve (obtaining such a sensor's a problem for higher engine >speeds). mmm OK got it, but why measure it when its known from the engine layout that its going to happen at combination of AFM, speed, etc > Even knowing the mean exhaust backpressure wouldn't be > sufficient on it's own to determine the degree of EGR. Flow > dynamics of the exhaust valve closing will often result in a > disproprotionately-high exhaust flow for the closing valve > as the columns of exhaust gas "sucks" harder through the > diminishing opening. mmm Interesting, >Any exhaust gases actually drawn back will add to the base EGR of >the engine and will be "cancelled out" by a reduced fresh mixture >intake. We can still calculate the AFR based on our knowledge of >volumetric efficiency of the engine. > >Prior testing with the engine will indicate appropriate ignition >timing to avoid knock at a particular AFR for a specific load/boost. Yes, does sound like a potential issue thats helpful, I need to think a little more how far I go on my own setup. I found out the other day, my block as 3 knock sensor locations along the length of the block though only the center one is used. Tah, Rgds ~`:o) Mike Massen Trading as "Network Power Systems" and "Network Computers" Perth, Western Australia Ph +61 8 9444 8961 Fx +618 9264 8229 (fax -> email) Products/Personal/Client web area at http://www.wantree.com.au/~erazmus (Current pics - trip to Malaysia to install equipment in jungle power site) Some say there is no magic but, all things begin with thought then it becomes academic, then some poor slob works out a practical way to implement all that theory, this is called Engineering - for most people another form of magic. - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 11:44:54 EST From: ECMnut@xxx.com Subject: Re: AFM measurement/backpressure (was Turbo speed sensor) Hi Grumper, waaay back in the early 60's, drag racers would cut a slot in the firewall, and stick and "arm" off the dissy, which they would move to retard the timing at high rpm, after they hit high gear. Crude but effective. The only caution, was exhaust temps increased noticably. Not a big deal for a few seconds.. MV You just don't see 56 Belairs with dual quad 327's anymore. > Sounds like your of the school, of as much timing as possible, rather then > then as little timing as consistent with max HP. The difference is what > lets engine win races, or live on the street. > - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Thu, 09 Mar 2000 01:23:42 From: "Mike (Perth, Western Australia)" Subject: Re: AFM measurement/backpressure (was Turbo speed sensor) At 11:44 AM 8/03/2000 EST, you wrote: >Hi Grumper, >waaay back in the early 60's, drag racers would cut a slot in the firewall, >and stick and "arm" off the dissy, which they would move >to retard the timing at high rpm, after they hit high gear. >Crude but effective. The only caution, was exhaust temps >increased noticably. Not a big deal for a few seconds.. Thats very similar to what I had in mind, as its quicker and easier then an ECU update (at the time). Run a diaphragm off the boost to a link which rotated the dizzy, the linkage is real simple and a lever arm of varying lengths would give varying amounts - my ECU apparantly doesn't retard timing at all. It was only meant for 7psi boost (3L, six T3 standard 60trim) so the simple mechanical setup would be ideal - though it would look strange on that model ~`:! Trouble is I really don't know how much retard I need for what boost :( Any idea (as a starting point) how much retard I should have from say 7psi to 10psi on a 3L six ? Tah :) Mike - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 10:13:59 -0700 From: "Chad" Subject: Re: O2 sensor Voltage I haven't read any of the ecm strategies, where can I get them (assuming you're not talking about ecu specific manuals)? If the ecu has some sort of time delay response, what if I output a square wave (minimum external hardware on the microcontroller) with a dc offset to trick the ecu? The way I understand O2 sensors, the output voltage will resemble a sine wave whose amplitude changes as the ecu adjusts for lean/rich conditions. >Might not be anywhere near that easy depending on your ecm. Have you read >about any of the ecm strategies for monitoring O2 v, and corrections?. >Some expect a specific response, and time delay from the O2 to changes in >injector timing. >Grumpy - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 12:14:05 -0500 From: "Swayze" Subject: Re: Electronic Transmission Control this is not an answer, but another question. which of the later OD GM trans should I look for,needing only TCC and 300HP+ survivability in a street driven car; 700R4,200??,4L60?,4L80? (BOP) my trans knowledge is from the twospeed TC powerglide days. byE Mike Swayze mswayze@xxx.com kswayze@xxx.net - ----- Original Message ----- From: "nacelp" To: Sent: Wednesday, March 08, 2000 11:43 AM Subject: Re: Electronic Transmission Control - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 12:27:17 -0500 From: "nacelp" Subject: Re: Electronic Transmission Control Any of those you mention assuming the 200??, means 200R4, can be built to withstand 350HP easily. The later the better, and for the 200R4 a buick turbo application would be best core. The 700R4/4L60 are the same basic design, the 4L the later. Trouble in my book is that dumb first gear of 3.06:1. The 200R4 is about 2.7ish as I recall, and the 4L80 2.5:1. So the 200R4, and 4L80 are the better ones, in my book. Less gear multiplication change during gear change, less chance of knock. Also, more like a close ratio tranny of the old days. With any 3.0+ rear gears the 3.06 first gear is great for lighting tires, but that's about all (other then AWD applications, where you need it to get all that mass acclerating). Grumpy > this is not an answer, but another question. > which of the later OD GM trans should I look for,needing only TCC and > 300HP+ survivability in a street driven car; 700R4,200??,4L60?,4L80? (BOP) > my trans knowledge is from the twospeed TC powerglide days. > byE > Mike > Swayze > mswayze@xxx.com > kswayze@xxx.net > ----- Original Message ----- > From: "nacelp" > To: > Sent: Wednesday, March 08, 2000 11:43 AM > Subject: Re: Electronic Transmission Control > > > > -------------------------------------------------------------------------- - -- > To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) > in the body of a message (not the subject) to majordomo@xxx.org > - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 12:37:57 -0500 From: "nacelp" Subject: Re: O2 sensor Voltage > I haven't read any of the ecm strategies, where can I get them (assuming > you're not talking about ecu specific manuals)? In the DIY+GMECM archives. If the ecu has some sort of > time delay response, what if I output a square wave (minimum external > hardware on the microcontroller) with a dc offset to trick the ecu? What if's ain't gonna work. You need to find out what strategy your ecm uses... The way > I understand O2 sensors, the output voltage will resemble a sine wave whose > amplitude changes as the ecu adjusts for lean/rich conditions. ECM, might use a high reference and low reference voltage, and measure the time, above or below those references for rich lean, not max voltage. Again, you got to figure out what you have. There are some clues, that you need to look at. ie, TBI/TPI, O2 sensor sees all cylinders, or just a few. Is it heated, close to to head, etc. Even better is hacing the code. Got to remember the oems in general make the stuff a little difficult so that the average Joe can't defeat it. They have to keep the emission folks happy, and part of that is durability. Meaning as ashless as possible for the O2 sensor itself. Grumpy > >Might not be anywhere near that easy depending on your ecm. Have you read > >about any of the ecm strategies for monitoring O2 v, and corrections?. > >Some expect a specific response, and time delay from the O2 to changes in > >injector timing. > >Grumpy - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 12:43:54 -0500 From: "nacelp" Subject: Re: AFM measurement/backpressure (was Turbo speed sensor) > Thats very similar to what I had in mind, as its quicker and easier then > an ECU update (at the time). Doesn't Dick Smith make a timing computer of some sort?. As I recall they had a dissy point eliminator that included a programmable devise, that or MSD (if they sell in Oz) has a multistep retard that is threee stages, that you can add together for like a total of 5 steps. Use a MAP sensor/comparator to trigger it. What ya gonna do for the extra fuel?. > > Run a diaphragm off the boost to a link which rotated the dizzy, the linkage > is real simple and a lever arm of varying lengths would give varying > amounts - my ECU apparantly doesn't retard timing at all. It was only > meant for 7psi boost (3L, six T3 standard 60trim) so the simple mechanical > setup would be ideal - though it would look strange on that model ~`:! > > Trouble is I really don't know how much retard I need for what boost :( Easy start with too much and tune from there. > Any idea (as a starting point) how much retard I should have from say > 7psi to 10psi on a 3L six ? I'd start at 10 and see where ya are. What about fuel?. Grumpy > Tah > :) Mike - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 09:42:47 -0800 From: "Cudabob" Subject: Re: Any electronically controllable gas regulators ? I came across mention of an injector/regulator, natural gas I believe, at www.jasperengines.com ... They build alternate fuel engines for California State Vehicles. > Date: Tue, 07 Mar 2000 22:34:42 > From: "Mike (Perth, WA)" > Subject: Any electronically controllable gas regulators ? > > Hi chaps, > > (As I'm new to this group, I apologise for so many postings so soon, > still gathering info - tah)... > > Petrol engine fuel injectors are dead easy to control from a micro, is > there a corrollary for any gas injection equipment etc. ? > > ie. Is there a (readily available) gas injection nozzle operable from > a 12v PWM signal and/or a gas regulator compensation for manifold > pressure, (Given the flow pressure differences I would think it > straightforward), for example for turbo engines thats comparable to > that simple fuel pressure regulator used on many petrol cars ? > > When I go ahead with my EFI project for my car (to replace existing > ECU), I would like the option of extending the control fully to a > bifuel gas system - LPG at first, then moving to CNG soon after and > all this with on load changeover between the two fuels Don't > ask for much ;-) > > > Tah, > CudaBob '65 - Angels Camp, Calif CudaBob@xxx.com http://www.goldrush.com/~rhuish/ - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 13:11:02 -0500 From: "nacelp" Subject: Re: AFM measurement/backpressure (was Turbo speed sensor) > Do I get the impresion that AFM's in the USA are mostly the flap type, None that I can recall. Lucas/Bosch systems use them, and patent leasees of them. Numerically probably MAP is most common, then hot wire, and then combos of MAP/hot wire. Grumpy > because here in Australia - most if not all (by now) are platinum hot wire ? > And on the latest V8's with 300 to 350Kw they are large 3" to 3.5" with > modified platinum hot wire - not all all restrictive... Maybe not seemingly so, but 30 HP is 30 HP. That was on a healthy turbo 231 CID engine. Grumpy > > > > Rgds ~`:o) > > Mike Massen Trading as "Network Power Systems" and "Network Computers" > Perth, Western Australia Ph +61 8 9444 8961 Fx +618 9264 8229 (fax -> email) > Products/Personal/Client web area at http://www.wantree.com.au/~erazmus > (Current pics - trip to Malaysia to install equipment in jungle power site) > > Some say there is no magic but, all things begin with thought then it becomes > academic, then some poor slob works out a practical way to implement all that > theory, this is called Engineering - for most people another form of magic. > > -------------------------------------------------------------------------- - -- > To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) > in the body of a message (not the subject) to majordomo@xxx.org > - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 13:21:11 -0500 From: "Swayze" Subject: Re: Electronic Transmission Control I had assumed the E after 4L80 was for electronic(computer) control. which suffix denotes just a TCC. (I am assuming the 4L80 is truck version(duty) of 200R4.) byE Mike Swayze mswayze@xxx.com kswayze@xxx.net - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 13:34:48 -0500 From: "nacelp" Subject: Re: Electronic Transmission Control Nope, electrically controlled shifting. Line pressures, and shift rpm, governed by PCM. Minor point, Powertrain Control Module, rather then ecm, ref engine. The 700R4/200R4, all used electrical TCCs Grumpy > I had assumed the E after 4L80 was for electronic(computer) control. which > suffix denotes just a TCC. > (I am assuming the 4L80 is truck version(duty) of 200R4.) > byE > Mike > Swayze > mswayze@xxx.com > kswayze@xxx.net > > -------------------------------------------------------------------------- - -- > To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) > in the body of a message (not the subject) to majordomo@xxx.org > - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 08 Mar 2000 12:44:03 -0600 From: MysticZ Subject: Re: Electronic Transmission Control Swayze wrote: > > this is not an answer, but another question. > which of the later OD GM trans should I look for,needing only TCC and > 300HP+ survivability in a street driven car; 700R4,200??,4L60?,4L80? (BOP) > my trans knowledge is from the twospeed TC powerglide days. My 4L60E isn't complaining about 350 horsepower or 400 foot pounds. It's not the horsepower that trashes a tranny, it's the torque. But with 300 HP, you shouldn't have a problem with a 700R4 or 4L60E. The -80E weighs a ton and the rest have no overdrive, so I'd stick with the 700R4/4L60E. - -- Steve 97 Chevy Camaro Z28, Mystic teal, A4, not stock 90 Kawasaki EX500A4, black, M6, not even CLOSE to stock! lt1_z28@xxx.net/~lt1_z28 Aluminum, steel, carbon fiber, titanium, and two cast iron balls. McMillan Motorsports- http://www.mmsbikes.com - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 13:44:32 -0500 From: "Swayze" Subject: Re: Electronic Transmission Control so, what were(are) the 200R4 trans available in? Swayze mswayze@xxx.com kswayze@xxx.net - ----- Original Message ----- From: "nacelp" To: Sent: Wednesday, March 08, 2000 1:34 PM Subject: Re: Electronic Transmission Control > Nope, electrically controlled shifting. > Line pressures, and shift rpm, governed by PCM. Minor point, Powertrain > Control Module, rather then ecm, ref engine. > The 700R4/200R4, all used electrical TCCs > Grumpy - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 08 Mar 2000 12:48:33 -0600 From: MysticZ Subject: Re: Electronic Transmission Control nacelp wrote: > > The 700R4/4L60 are the same basic design, the 4L the later. Trouble in my > book is that dumb first gear of 3.06:1. > The 200R4 is about 2.7ish as I recall, and the 4L80 2.5:1. > So the 200R4, and 4L80 are the better ones, in my book. Less gear > multiplication change during gear change, less chance of knock. Also, more > like a close ratio tranny of the old days. With any 3.0+ rear gears the > 3.06 first gear is great for lighting tires, but that's about all (other > then AWD applications, where you need it to get all that mass acclerating). The low 1st of the 700R4 and 4L60E are one of the strong points! It lets you put a sane gear in the rear end (3.23 or 3.73) and still have an efficient overdrive. While I can spin the tires at will, when I need them to stick, they will stick. But then there is the fact that there's 12" of very sticky rubber back there... ;) - -- Steve 97 Chevy Camaro Z28, Mystic teal, A4, not stock 90 Kawasaki EX500A4, black, M6, not even CLOSE to stock! lt1_z28@xxx.net/~lt1_z28 Aluminum, steel, carbon fiber, titanium, and two cast iron balls. McMillan Motorsports- http://www.mmsbikes.com - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 12:55:07 -0600 (CST) From: Roger Heflin Subject: Re: Electronic Transmission Control On Wed, 8 Mar 2000, Swayze wrote: > this is not an answer, but another question. > which of the later OD GM trans should I look for,needing only TCC and > 300HP+ survivability in a street driven car; 700R4,200??,4L60?,4L80? (BOP) > my trans knowledge is from the twospeed TC powerglide days. Any tranny with an E after it would requre the expensive computer to control it. THere is a 700R4 and a 4L60 (no E) that only have TCC inputs, they also have outputs for VSS, and to tell the computer what gear it is in (if the computer cares). The 4L60 is basically a 700R4 so longs as the 4L60 does not have an E after it. My 4L60 survived for 120k with at least 20k of that with a 370rwhp engine. The thing that wore out was the 4th gear band and the 3-4 clutch back. Both were though to be from excessive mileage, and not excessive hp. Roger - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 12:59:54 -0600 (CST) From: Roger Heflin Subject: Re: Electronic Transmission Control On Wed, 8 Mar 2000, Swayze wrote: > I had assumed the E after 4L80 was for electronic(computer) control. which > suffix denotes just a TCC. > (I am assuming the 4L80 is truck version(duty) of 200R4.) > byE E means fully electronic, without the E is usually just TCC. >From what I have heard about the 4L80 is phyiscally much much bigger than a 200R4. I was told a 200R4 weights less than a 4L60 (700R4) and the 4L80 is said to be at least 100lbs heavier (probably more) than a 700R4, and also is is much physically larger than a 4L60 (to fit it in my car requires application of a hammer at key tranny tunnel locations). 93 f-bodies have 4L60's, 94+ f-bodies have 4L60E trannies. Roger - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ Date: Wed, 8 Mar 2000 13:58:54 -0500 From: "Gwyn Reedy" Subject: RE: Electronic Transmission Control The 4L80 is the overdrive successor to the THM-400 and the 4L60 is the successor to the 700R4 which was the overdrive successor to the THM-350. There were 4L60 that were not computer controlled and the 4L60E which is. Dunno if there was ever a 4L80 without the E. I've got a big block pickup with a THM-400 and that transmission just won't give up. Often pull loads of 25000 pounds with it. Have had some rear end trouble, though So I want the 4L80 for the THM-400 toughness plus the overdrive so I can run a lower gear. Gwyn > -----Original Message----- > From: owner-diy_efi@xxx.org]On > Behalf Of Swayze > Sent: Wednesday, March 08, 2000 1:21 PM > To: diy_efi@xxx.org > Subject: Re: Electronic Transmission Control > > > I had assumed the E after 4L80 was for electronic(computer) control. which > suffix denotes just a TCC. > (I am assuming the 4L80 is truck version(duty) of 200R4.) > byE > Mike > Swayze > mswayze@xxx.com > kswayze@xxx.net > > ------------------------------------------------------------------ > ---------- > To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without > the quotes) > in the body of a message (not the subject) to majordomo@xxx.org > - ---------------------------------------------------------------------------- To unsubscribe from diy_efi, send "unsubscribe diy_efi" (without the quotes) in the body of a message (not the subject) to majordomo@xxx.org ------------------------------ End of DIY_EFI Digest V5 #92 **************************** 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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