DIY_EFI Digest Tuesday, February 1 2000 Volume 05 : Number 049 In this issue: RE: Mopar heated O2 sensor question Re: water injection SV: DFI vs TEC II re: programming under boost questions Re: New member, programming under boost questions RE: Information regarding ECU6.. Re: water injection RE: DIY_EFI Digest V5 #42 Re: Electro-magnetic valves Re: camless engine Re: Large P&H Port Injectors Fw: LT1 with boost. RE: LT1 with boost. Re: LT1 with boost. Re: Large P&H Port Injectors RE: LT1 with boost. Re: DIY_EFI Digest V5 #48 Re: DIY_EFI Digest V5 #48 RE: DIY_EFI Digest V5 #48 Can anybody Identify these Components Can anybody Identify these Components Re: water injection B16A wiring diagrams See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Tue, 1 Feb 2000 14:54:52 -0000 From: "Rich M" Subject: RE: Mopar heated O2 sensor question The 4-wire heated sensors I have dealt with (mainly Bosch), incorporate a positive temperature coefficient function in the heater, so as the sensor heats up the resistance increases, reducing the current drawn from 12V supply, while maintaining temperature. You can check this easily; apply 12V power to the heater and measure the current as it warms up - if the current drops off then it's probably OK to connect to ignition switched 12V supply. My experience is mainly Bosch Motronics, this is what they do. Rich > -----Original Message----- > From: owner-diy_efi@xxx.org]On > Behalf Of Will McGonegal > Sent: 31 January 2000 23:41 > To: diy_efi@xxx.org > Subject: Mopar heated O2 sensor question > > > I have a four wire heated O2 sensor from a Chrysler (p.n. > 5233088). I believe that the > heater inside it can be powered continuously by 12 volts. Does > anyone know if this is > not the case? Perhaps there is a more complex scheme for > regulating the sensor > temperature that I am not aware of (e.g.. measuring current and > voltage into heater, > calculating resistance, therefore knowing the temperature). > - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 11:01:11 -0600 From: "Andrew Theurer" Subject: Re: water injection Concerning water injection and atomization, has anyone considered using a fuel rail and fuel injectors to do this? I'm thinking of using my existing stock injectors, fuel pressure regulator, and maybe fuel pump (and small fuel cell) to run my water injection, controlled by one of my efi332 ECU's. I'll need to step up to bigger injectors for fuel anyway (probably 860cc), so I might as well make use of the old parts. Anyone see any problem delivering water this way? Seems to me to be the safest & most accurrate way to do this. Now, the ulimate is to have the water injection ECU read EGT, and knock (maybe from J&S), and alter is "water map" to accomidate varying conditions. Just a thought.... - -Andrew - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 17:13:15 +0100 From: "Ola Marvik" Subject: SV: DFI vs TEC II Va d no du ville meg?? - ----- Original Message ----- From: Frederic Breitwieser To: Sent: Tuesday, April 13, 1999 10:52 PM Subject: Re: DFI vs TEC II > >types of software available, such as MAP, MAF. However, by time you pay > >for the software license, the TEC II seems to be more expensive. > > Actually I did in fact reply to your message... however I just built a new > server because the old one foobar'd, therefore maybe it didn't make it > through successfully. > > I have a fair amount of experience with Haltach and TecII, and for a forced > induction engine, its a mere toss-up. The one major, major advantage of the > TEC-II is that its an under-hood bolt together system that uses OEM sensors > (or Electromotive sensors - same thing) using spade connectors. The TEC > units have screw terminals everywhere, and you can interface this to your > engine very easily. Go to the junkyard, buy sensors, and take the wires > going to said sensors and cut them as far back as you can. Reduces the > price significantly actually. The software is very expensive, however it is > as flexible as you can imagine. Boost, no boost, MAP/MAF, etc, and you can > change your configuration very easily as you add one or two turbochargers > . > > I think compared between the two, the TEC II is the leader. Bolt it to your > firewall, and its done. > > - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 09:05:48 -0800 From: "John Dammeyer" Subject: re: programming under boost questions > >Date: Mon, 31 Jan 2000 15:59:36 -0800 >From: Dave Plummer >Subject: New member, programming under boost questions > [snip] >My big question is about the WOT Enrichment vs. RPM table. It's described >in some places as specifying a desired AF ratio, in others as a percentage >of extra fuel to add during WOT. Which is more accurate? How does the O2 >sensor get figured into this blanket enrichment at WOT? At WOT we disable O2 sensor feedback so the software isn't trying to alter a deliberate enrichment. As I see it, too much fuel at WOT provides cooling reduces power. Too little fuel (below 14.7:1) and you end up with EGT that is high and not enough energy to increase RPM. In other words our top end experiments on the dyno have shown that there is a definite 'window' and there is a reduction in power outside of that window. When we use a load (the Giant Computer Fan) that limits the RPM of the engine we find at 5900RPM that maximum fuel required to accelerate up to that speed is higher than the fuel required to stay there. ie: If we hold the engine at 5600RPM with, say, 8.9ms PW on the injectors, we need as much as 12ms to accelerate but once at 5900RPM we can reduce PW to 9.3ms and not have the RPM drop nor the EGT climb excessively high; about 1400F. Adding more fuel at 5900RPM just reduces the EGT without increasing the RPM. > >My second question relates more specifically to accommodating boost. Since >the VE tables are limited to 100%, what's the best way to program for boost? >I'm thinking this: > >1) In the RPM range where boost is present, in the 100kPa column, set VE to >100% >2) Get the extra fuel to accommodate the true >100% VE by upping the WOT >enrichment table entries What I've been able to find out about VE is that it represents the amount of air that will flow through the intake manifold at WOT at various engine RPM assuming constant Atmospheric Pressure. This is why the ratio of MAP/Barometer is used to modify with the VE value; Change the atmospheric pressure and you change the velocity of the air moving through the intake manifold. At a lower RPM the air mass has to stop and start and bounces against the end of the plenum and the intake valves. At higher RPM the air doesn't have to stop as often or for as long a period of time so you start getting more air into each cylinder while the valve is open. Think of it this way. If you had air that had no mass, then, when the intake valve opens the cylinder would immediate reach ambient air pressure; then the valve would close. At idle, you'd then inject the correct amount of fuel to match that air charge assuming 14.7:1. Well, with that much air and fuel you wouldn't stay at idle for very long because the power produced would accelerate the piston to a higher speed rather than what maintain the value of torque for idle. The above is based on the assumption that the air has no mass and accelerates instantly but in real life it doesn't happen that way; it takes time for the air to start and stop moving. Now if you load the engine so it cannot go faster than 1000RPM, and you open the throttle wide, the amount of air going into each cylinder is less than the cylinder can hold at atmospheric pressure because the air isn't moving when the intake valve opens. It then has to start moving and flow into the cylinder. Before the cylinder is full, the intake already closes. In other words, once the intake valve closes, the air pressure inside the cylinder is less than ambient because the piston moving down created an empty space that wasn't completely filled during the time that the intake valve was open. Your Turbo Charger changes this which is why at any given RPM the load required to hold the 1000 RPM constant at WOT is larger. The Turbo, by raising the pressure at the inlet of the manifold accelerates the air mass so that it flows into the cylinder faster (over time more air is ingested) resulting in more air available for combustion. So the VE table represents how well the air flows into the cylinders based on the RPM where 100% VE implies that when the intake valve closes the air pressure inside the cylinder is at atmospheric pressure. Longer runners verses shorter runners move the torque around and the internal shape and volume also changes engine performance. The newer Honda engines and even the Mercedes SUV modifies the intake manifold by opening and closing a passageway inside the plenum at certain RPM values. My guess is that if your VE[RPM] table is correct for a non-aspirated engine, the MAP/Ambient ratio will compensate for the boost because the ratio is now > 1 and therefore VE[RPM] * MAP/Ambient will result in values greater than 100% VE. IMO > >I can't really do #2 without understanding that table a little better, hence >the original question. Any feedback on how I should go about programming >the LT1 controller for boost would be greatly appreciated! > Can't help you there. >Thanks, >Dave > Regards, John Dammeyer - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 09:16:52 -0800 From: "Dave Plummer" Subject: Re: New member, programming under boost questions > > My first goal, under the heading of "learn on the old motor first", is to > > eliminate the FMU and alter the spark tables to be better suited to the > > blown application. > > I don't see the logic in eliminating the FMU. It's the only thing raising > your fuel capacity. It's barely needed on a stock LT1 as it is (the car has a MAF), and I'll be using larger injectors for the larger motor. > If you don't have enough fuel, still will be lean. Or possibly too much (I > doubt) Then how to other tuners accomplish this? > The LT1 is stock form has no accomodation for boost. To do this right you > need for the calibration to see what the engine load is. Que? Without the FMU right now with stock programming the 02 values are low 800s. All I need to do is get it up to about 880mv, and I don't think I believe there's not enough capacity in the stock fuel system. - - Dave - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 10:09:55 -0800 From: "Al Lipper" Subject: RE: Information regarding ECU6.. Ali, I'll try to provide what info I can. Scaling Constant (SC) is to convert the byte value stored in the fuel table (IVV) into a pulse width. For example, if a value looked up in the table should produce a pulse width (PW) of 1512us (1.5ms), it might have an IVV of 36 (the byte looked up in the main fuel map) and the SC would be 42 (for the whole table). THe SC is because the table can only store a 0-255 value, so we need a way tp represent a large number like 1512. "TA" is an abreviation for Trans Am, the model of car I tested this on - this spreadsheet contains data for that car. Scaling Constant is for engine temperature compensation. Is increased by a percentage using this value for cold operation. Look at the {CALC_PW} routine in ECU6 for the detailed math. Scaling constant is read from the table into CLV%. There is no easy way to get tables for other cars - check on Holley's web site, they might have some that can be converted using the excel macros in the spreadsheet. But really, you adjust them on your car until they work. The thing to remember is that your car will run with an excessively rich mixture, but not really at all with anything more than a slightly lean mixture. Good luck. Al > -----Original Message----- > From: Ibrahim [mailto:u961036@xxx.pk] > Sent: Sunday, January 30, 2000 5:33 AM > To: efi@xxx.org > Subject: Information regarding ECU6.. > > > Dear Mr. Lipper > I am sorry i am mailing again and again, but i simply have to get > some vital > information regarding certain aspects of your project. We > unfortunately have > no teachers here that could explain to us in detail the circuit > diagrams and > the lookup tables. > Regarding the circuit diagrams i mailed to you earlier. I have > problems now > understanding the lookup tables. There are certain terms that need > explanation plus some more information on how to interpret the > tables. The > terms that need explanation are Fuel Factor, IVV, TA,etc. > How do we get lookup tables for other cars? Please send me all of > this info > as soon as you comfortably can. I'll be truly grateful. > Ali Hasan. > > - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 13:41:15 -0500 From: "nacelp" Subject: Re: water injection The down sides to running water thru the injectors have been covered in detail in the archives. Personally, I'm going to use AN, SS, and brass, then plumb it as a very high pressure system (ie 200 PSI). If you run water thru the oem stuff, figure on replacing components often. Grumpy > Concerning water injection and atomization, has anyone considered using > a fuel rail and fuel injectors to do this? I'm thinking of using my > existing stock injectors, fuel pressure regulator, and maybe fuel pump > (and small fuel cell) to run my water injection, controlled by one of my > efi332 ECU's. I'll need to step up to bigger injectors for fuel anyway > (probably 860cc), so I might as well make use of the old parts. Anyone > see any problem delivering water this way? Seems to me to be the safest > & most accurrate way to do this. Now, the ulimate is to have the water > injection ECU read EGT, and knock (maybe from J&S), and alter is "water > map" to accomidate varying conditions. Just a thought.... > > -Andrew > > -------------------------------------------------------------------------- - -- > 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: Mon, 31 Jan 2000 20:31:53 +0000 From: Ade + Lamb Chop Subject: RE: DIY_EFI Digest V5 #42 At 10:05 31/01/00 -0700, Greg Hermann wrote: >>I have talked to several GM engineers and the solenoid replacement of >>camshafts has been and is in the development stages. The major stumbling >>block is the fact that to operate the solenoids they need about 32 volts and >>the car companies do not want the expense of changing all the electrical >>systems in the car . >> >The 32 volt--or higher-electrical systems are coming, and soon. Betcha they >happen LONG before solenoid operated engine valves! > >Also betcha that the first engines with anything resembling solenoid >operated valves are about as long lived and popular as the Vega engines >were! Vega?? I think I have just made you point! So what is a Vega engine then? Ade - ---------------------------------------------------------------------------- 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: Mon, 31 Jan 2000 20:29:13 +0000 From: Ade + Lamb Chop Subject: Re: Electro-magnetic valves At 10:37 31/01/00 -0700, Greg Hermann wrote: >>Yamaha has a prototype 250 cc. with 4 (2 inlet 2 exhaust) >>electromagnetic valves being dyno tested at the University of California >>at Riverside. It's an interesting idea but it takes quite a control >>system to manage the valves and a large (150V 30A) DC power supply. I >>think there's an SAE paper on this but I can't find the reference at the >>moment. >> >>Hope this helps, >> >>Mac > >Gee--4500 watts to run the valves. That's about 5.5 HP. A pretty >significant portion of a 250 cc's output, But it takes a significant amount >of power to drive a camshaft, too. What is more significant is that the >efficiency losses in the generator and the solenoids are probably at least >1.5 HP! Yes but think how much power the cam drivetrain loses... Big heavy springs, cogs, belts/chains. It cannot be that far off 5HP. Ade - ---------------------------------------------------------------------------- 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: Mon, 31 Jan 2000 20:34:34 +0000 From: Ade + Lamb Chop Subject: Re: camless engine At 10:30 31/01/00 -0700, Greg Hermann wrote: >Long ago, had the fun of talking to a guy who had worked for Thompson Valve >(now the "T" in TRW) about the hydraulic pressures that are encountered in >hydraulic (self-adjusting) lifters. These are not only the sort of >pressures you would be dealing with, but trying to switch on and off and >start and stop the flow--consider the inertia in the fluid itself, as well >as the weight of the valve. They are easily comparable the the higher range >of diesel fuel injection pressures--2000 BARs!! (About 30,000 psi). > >Not saying it is not possible, just not too likely any time soon. > >Variable valve LIFT is not to important. Variable valve timing and duration >has a LOT of potential. As is already being done, the most likely >practical way of achieving it is with hydraulic/mechanical adjustment of >the cam timing, and possibly next with multiple cam lobes per valve. >Variable lift can be achieved on a practical basis with variable rocker >geometry--and this is already being done, although not on a mass production >basis. How does Rovers VVC and Hondas Vtec stuff do it? Ade - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 12:02:10 -0800 (PST) From: Anthony Buccellato Subject: Re: Large P&H Port Injectors 1) The Rochester's are not tolerant of substantially increased fuel pressure. On a hot day, with a 4/1 amp driver, do not expect to operate a Rochester at much over about 55 psig without fear that it will fail to open against the prevailing internal hydraulic pressure. Whereas, I have been able to operate some of the Bosch injectors as high as 140psig, which allows a huge window of tuning opportunity down the road without having to fork over considerable $$$ for new injectors. 2) At low base pulse widths, with a 4/1 amp driver, the Rochester's exhibit more irregularity and nonlinearity IMHO. I'm glad you mentioned that. It doesn't take much imagination to foresee an expensive motor explosion under boost, when the injector doesn't fail to open entirely, but just reduces the fuel somewhat. Sounds like Bosch is it. Yes, some of the Bosch Motorsport injectors are available in stainless steel form (either internally or externally or both) for use with alcohol based and other nasty fuels. However, even though your application is for marine use sounds like you as using "gas" which should be compatible with normal non-SS injectors. Hopefully you don't have that much water in your fuel :) It's not the water in the fuel I'm worried about, it's water on the outside of the injectors. With few exceptions, SS is generally the way to go in a boat. I'll look forward to the photos. - - Clay - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 15:57:15 -0500 From: "nacelp" Subject: Fw: LT1 with boost. A friend of Doc's show the posting, and mentioned the following to him in passing... Grumpy > 1. VE is only used for backup mode if the MAF fails, so forget it for now. > 2. All fueling is calculated from MAF (until you max out. . .335 grams impala, 471 grams F/Y car) > 3. The PE/RPM table is a % change to base A/F ratio with higher numbers > making the mixture richer. If you max the sensor, you just have to go 'over-rich' > in the table at that RPM point. Easy to do, no problem, works fine. > 4. If you have the reprogramming capabilities (a friends shop, in my case) FMU's suck. - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 13:24:54 -0800 From: Dave Plummer Subject: RE: LT1 with boost. Two questions, then: 1) Why is an FMU required on a MAF car at all, then? Shouldn't it just see the amount of air going through and add the right amount of fuel "automagically"? 2) Are there MAF <-> FUEL tables anywhere in the PCM? I've never seen them in the '94/95 LT1 pcms. Or is it just a formula? - - Dave > > 1. VE is only used for backup mode if the MAF fails, so > forget it for > now. > > 2. All fueling is calculated from MAF (until you max out. > . .335 grams > impala, 471 grams F/Y car) > > 3. The PE/RPM table is a % change to base A/F ratio with > higher numbers > > making the mixture richer. If you max the sensor, you > just have to go > 'over-rich' > > in the table at that RPM point. Easy to do, no > problem, works fine. > > 4. If you have the reprogramming capabilities (a friends > shop, in my > case) FMU's suck. - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 16:44:23 -0500 From: "nacelp" Subject: Re: LT1 with boost. > Two questions, then: > 1) Why is an FMU required on a MAF car at all, then? Shouldn't it just see > the amount of air going through and add the right amount of fuel > "automagically"? I think you might hit the archives, and get the address phone number that I posted about gm training manuals, and or read the archives a few more times, to get a better basic grasp of what your dealing with. > 2) Are there MAF <-> FUEL tables anywhere in the PCM? I've never seen them > in the '94/95 LT1 pcms. Or is it just a formula? MAFs don't use a fuel table, as you would think of/or seen like an ignition one. It is a "string" of corrections. Try reading the 165 Hac at the ECMGUYs site To get a grasp of what your looking at just don't look for LT1 answers, read all you can about gm ecms, then figure out how it applies, to your application. Might sound like I'm playing with words there, but that is the only way that I'm starting to get it. 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: Tue, 1 Feb 2000 13:44:02 -0800 (PST) From: Anthony Buccellato Subject: Re: Large P&H Port Injectors A little reality check... Bosch Motorsport (76 lb or 160 lb) cost $240 each. Rochester 96 lbs are $65 each. As always, cost comes into the equation. $2K for injectors isn't an option, at least for this season. I guess I'll just have to work within the limits of the inferior unit, and keep fuel pressure at appropriate levels. Shoulda seen this coming... - - Clay - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 14:02:07 -0800 From: Dave Plummer Subject: RE: LT1 with boost. > I think you might hit the archives, and get the address phone > number that I > posted about gm training manuals, and or read the archives a > few more times, > to get a better basic grasp of what your dealing with. I've been through the archives fairly thoroughly... Sorry if my naivety makes you grumpy. If you can recommend a query to run against the archives that would be particularly helpful in this case, feel free to suggest it. I did read every one with the word "MAF" in it, however, and this wasn't addressed specifically (I was admittedly searching the GM archives, though). - - Dave - ---------------------------------------------------------------------------- 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: Tue, 01 Feb 2000 17:21:43 -0500 From: Glen Beard Subject: Re: DIY_EFI Digest V5 #48 > Date: Tue, 1 Feb 2000 00:44:28 -0500 > From: "nacelp" > Subject: Re: New member, programming under boost questions > > > > My first goal, under the heading of "learn on the old motor first", is to > > eliminate the FMU and alter the spark tables to be better suited to the > > blown application. > > I don't see the logic in eliminating the FMU. It's the only thing raising > your fuel > capacity. The FMU is very inconsistent when it comes to increasing the fuel pressure in relation to boost. It's not even a proportional rising rate. On one run it might have A/F right on while the next run it's way off. This device has already cost me an expensive rebuild because I leaned out at WOT. It's not the only thing raising fuel capacity. The goal here is to install larger injectors, set the fuel pressure back down where the injectors are rated for and calibrate the PCM for max power. Currently I run about 95# fuel pressure through my stock 24# injectors at 6# boost. The problem comes in where, as you stated, the LT1 has no provisions for boost. The question is how to accomplish this using the existing PCM programming while altering the EEPROM tables using the recently written LT1 Editor program. Dave has written to me asking the same questions. He wants to know if there is a way to help the PCM accommodate boost. Short of a completely different program, I think we are stuck on fooling it into thinking 14.7psia (1 bar) is actually 6# or 10# boost. As far as I know there is no way to get the PCM to properly use a 2 bar MAP. Am I wrong here? With enough changing tables could you get the PCM to work correctly using a 2 bar MAP? - -- Glen Beard 95 T/A conv M6 355, Vortech, heads, cam... http://home.nycap.rr.com/gbeard1/TransAm.html - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 17:43:42 -0500 From: "nacelp" Subject: Re: DIY_EFI Digest V5 #48 > > I don't see the logic in eliminating the FMU. It's the only thing raising > > your fuel > > capacity. > The FMU is very inconsistent when it comes to increasing the fuel > pressure in relation to boost. It's not even a proportional > rising rate. On one run it might have A/F right on while the > next run it's way off. This device has already cost me an > expensive rebuild because I leaned out at WOT. So you got a junk FMU, then. That's all that says, same logic would be I got a bad brandx spark plug so I'm coverting to diesel. Sounds like you've heard so many rumors that you've fallen into agreement with them. Which is fine, but saying FMUs don't work, or it cost you an engine is an error, IMHO. If you had been monitoring things closer it wouldn't have happened. > It's not the only thing raising fuel capacity. The goal here is > to install larger injectors, set the fuel pressure back down > where the injectors are rated for and calibrate the PCM for max > power. Currently I run about 95# fuel pressure through my stock > 24# injectors at 6# boost. Oh, and had you mentioned that before??... What pump are you running that has enough flow at 95 PSI to support your engine?. Have you actually tested to be sure there is an excess of fuel?. Were you trying to run the FMU at 95ish PSI?. Did you find out if it would work at that level to begin with?. The problem comes in where, as you > stated, the LT1 has no provisions for boost. The question is how > to accomplish this using the existing PCM programming while > altering the EEPROM tables using the recently written LT1 Editor > program. All you can do with the existing editor's is set things for when the sensors max out. Ya need to rethink your strategy. The hardware, AND software have to work together...... Grumpy > > Dave has written to me asking the same questions. He wants to > know if there is a way to help the PCM accommodate boost. Short > of a completely different program, I think we are stuck on > fooling it into thinking 14.7psia (1 bar) is actually 6# or 10# > boost. As far as I know there is no way to get the PCM to > properly use a 2 bar MAP. Am I wrong here? With enough changing > tables could you get the PCM to work correctly using a 2 bar MAP? Not from what I've seen, it takes a program change. Are ya'all running MAP, MAF, or both?. Meaning have you defaulted to one?. If your running MAF do what the guy told doc to do!. Use the large MAF. Bruce > > -- > Glen Beard 95 T/A conv M6 > 355, Vortech, heads, cam... > http://home.nycap.rr.com/gbeard1/TransAm.html > -------------------------------------------------------------------------- - -- > 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: Tue, 1 Feb 2000 14:55:29 -0800 From: Dave Plummer Subject: RE: DIY_EFI Digest V5 #48 First, stop me if I'm wrong: On a speed density system (like a '93), I assume the PCM computes airflow as a function of tps, rpm, and ve. Thus, knowing where the throttle is, how fast the motor is spinning, and how efficient the motor is at filling itself at that rpm, the ECM can calc the amount of air flowing and work from there. On a MAF system, it can do that as well as measure it directly. On an SD system under boost, obviously its wrong, so you can add extra fuel via the power enrichment table to compensate for its "error". You basically tell it to shoot for some ratio like 10:1, it does it based on the amount of air it thinks should be flowing, but with the amount of air -really- flowing, you wind up at the desired 12:1 (or whatever). And so, THE QUESTION: But on a MAF system, why do you need to at all until you max the MAF? As long as you're still in the MAF range, why can't the PCM just "do the right thing" based on the amount of air it measures at the MAF? And, what does the PCM do when the MAF values are wildly different than the tps*rpm*ve calculation? Does it get upset and trigger the airbag, or what? Thanks! Dave > -----Original Message----- > From: Glen Beard [mailto:gbeard1@xxx.com] > Sent: Tuesday, February 01, 2000 2:22 PM > To: diy_efi@xxx.org > Subject: Re: DIY_EFI Digest V5 #48 > > > > Date: Tue, 1 Feb 2000 00:44:28 -0500 > > From: "nacelp" > > Subject: Re: New member, programming under boost questions > > > > > > My first goal, under the heading of "learn on the old > motor first", is to > > > eliminate the FMU and alter the spark tables to be better > suited to the > > > blown application. > > > > I don't see the logic in eliminating the FMU. It's the > only thing raising > > your fuel > > capacity. > > The FMU is very inconsistent when it comes to increasing the fuel > pressure in relation to boost. It's not even a proportional > rising rate. On one run it might have A/F right on while the > next run it's way off. This device has already cost me an > expensive rebuild because I leaned out at WOT. > > It's not the only thing raising fuel capacity. The goal here is > to install larger injectors, set the fuel pressure back down > where the injectors are rated for and calibrate the PCM for max > power. Currently I run about 95# fuel pressure through my stock > 24# injectors at 6# boost. The problem comes in where, as you > stated, the LT1 has no provisions for boost. The question is how > to accomplish this using the existing PCM programming while > altering the EEPROM tables using the recently written LT1 Editor > program. > > Dave has written to me asking the same questions. He wants to > know if there is a way to help the PCM accommodate boost. Short > of a completely different program, I think we are stuck on > fooling it into thinking 14.7psia (1 bar) is actually 6# or 10# > boost. As far as I know there is no way to get the PCM to > properly use a 2 bar MAP. Am I wrong here? With enough changing > tables could you get the PCM to work correctly using a 2 bar MAP? > > -- > Glen Beard 95 T/A conv M6 > 355, Vortech, heads, cam... > http://home.nycap.rr.com/gbeard1/TransAm.html > -------------------------------------------------------------- > -------------- > 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, 02 Feb 2000 13:33:44 +1100 From: Richard Wakeling Subject: Can anybody Identify these Components Hi All, Can anybody identify these components. They are out of a TECH 1 scan tool. They all look the same but their numbers are different. Note: where the asterisk sits is a symbol of a diode. 1) IRFD Y4I * RC9 110 2) IRFD Y9I * RM4 1Z3 3) IRFD Y4I * RJ9 9113 Here's exactly what they look like. http://ixoye.com/irfd123.html I cant find any specs on the ones I have above. Lastly and I think this ones going to be difficult to identify. Its markings are Vtx85011011. It has 11 pins in one row and looks like a resister array with brown coating. TIA Cheers Richard. PS Nice to here from you DIG. - ---------------------------------------------------------------------------- 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, 02 Feb 2000 13:42:09 +1100 From: Richard Wakeling Subject: Can anybody Identify these Components Hi All, Can anybody identify these components. They are out of a TECH 1 scan tool. They all look the same but their numbers are different. Note: where the asterisk sits is a symbol of a diode. 1) IRFD Y4I * RC9 110 2) IRFD Y9I * RM4 1Z3 3) IRFD Y4I * RJ9 9113 Here's exactly what they look like. http://ixoye.com/irfd123.html I can't find any specs on the ones I have above. Lastly and I think this ones going to be difficult to identify. It's markings are Vtx85011011. It has 11 pins in one row and looks like a resister array with a brown coating. TIA Cheers Richard. PS Nice to here from you DIG. - ---------------------------------------------------------------------------- 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: Tue, 1 Feb 2000 21:15:02 -0700 From: bearbvd@xxx.net (Greg Hermann) Subject: Re: water injection >Concerning water injection and atomization, has anyone considered using >a fuel rail and fuel injectors to do this? Yep. Planning to use injectors rated for alky and stainless rails, tho. - ---------------------------------------------------------------------------- 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: Sun, 30 Jan 2000 23:27:45 -0800 From: "Scott Croughwell" Subject: B16A wiring diagrams You might want to try this site: http://hybrid.honda-perf.org/tech/info.html#ECUpinout The site covers all sorts of Honda tech (mostly for engine swapping) and the wiring diagrams appear to be quite complete. Scott - ---------------------------------------------------------------------------- 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 #49 **************************** 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".