DIY_EFI Digest Monday, 8 February 1999 Volume 04 : Number 096 In this issue: Re: OBD II LT1 Engine Swap Gotchas??? Re: MAP manipulations Re: fusible link questions Re: A little too simple Re: Digital: fuel pressure gage; boost gage Re: gmecm list Re: Digital: fuel pressure gage; boost gage Re: Digital: fuel pressure gage; boost gage Re: A little too simple Re: fusible link questions Re: fusible link questions WTD: Info on a Rotomaster/rayjay turbo Re: fusible link questions Re: Digital: fuel pressure gage; boost gage Re: fusible link questions Re: fusible link questions Re: Digital: fuel pressure gage; boost gage Re: WTD: Info on a Rotomaster/rayjay turbo Re: fusible link questions Re: fusible link questions Re: WTD: Info on a Rotomaster/rayjay turbo Looking for specs for a GM MAF Re: fusible link questions Re: fusible link questions Re: Looking for specs for a GM MAF Re: Looking for specs for a GM MAF Newbie ALDL question Re: fusible link questions Re: fusible link questions RE:Digital fuel pressure gauge See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: xxalexx@xxx.com Date: Sun, 7 Feb 1999 08:52:36 +0000 Subject: Re: OBD II LT1 Engine Swap Gotchas??? > Date: Wed, 03 Feb 1999 16:26:23 -0500 > Subject: Re: OBD II LT1 Engine Swap Gotchas??? > To: diy_efi@xxx.edu > From: "Andrew K. Mattei" > Reply-to: diy_efi@xxx.edu > "David A. Cooley" wrote: > > >Pre OBD_I? But that would mean using an ECM that's pre 1988. > > > > Actually, the 94/95 was more like OBD_I 1/2... 93 and earlier should work > > without the rear sensor > > I'll give you the OBD 1 1/2 - I can't use a paper clip to flash SES > codes on my '94 Z28. However, there is *no* O2 sensor after the cat. > Know that for a fact. The stock exhaust is sitting in my garage storage > closet - and it butts right up to the cat... > > Plus, the ALDL info available is significantly more for the '94/95 than > there was for the '93. Not that more is better, there's just more > there... ;) > Could be a calif. obd2 phase in car. 20% per yr. starting 94. alex ------------------------------ From: xxalexx@xxx.com Date: Sun, 7 Feb 1999 08:52:36 +0000 Subject: Re: MAP manipulations I tried a simple 5V level shifter for a Bosch LH for a few minutes using a PIC 73 with 10 bit PWM output seemed to work ok. Also made 3 for L jet for German emissions conversions. They modified air meter output. used a 16 pt ram offset table based on input. alex > Are there any current designs or thoughts on modifying the output of a 5v > MAP sensor. > > 1. Moving the output up or down by a fixed amount over the entire operating > range. > > 2. Change the gain of the output up or down. > > 3. Not letting the output exceed 5v. > > An example of one is here but it costs 300 and 500 respectively. > http://www.splitsec.com/products/arc1/arc1ds.htm > > http://www.splitsec.com/products/arc2/arc2ds.htm > > If you have any ideas please share. > > John Falb > > ------------------------------ From: bearbvd@xxx.net (Greg Hermann) Date: Sun, 7 Feb 1999 09:21:17 -0700 Subject: Re: fusible link questions > >I've no idea what current is normally presant in the field windings, but I >wouldn't expect it to be large, and I would expect that it could be increased >significantly before you have problems with overheating. IIRC, .4 or .6 amp neighborhood. Besides, just spin it a bit faster with the same field current, and you will have higher voltage. You would only need the higher field (rotor) current in order to get the output voltage up at lower rpm. Regards, Greg ------------------------------ From: Onebil2mny@xxx.com Date: Sun, 7 Feb 1999 11:26:03 EST Subject: Re: A little too simple In a message dated 2/6/1999 7:24:53 PM Eastern Standard Time, quest100@xxx.net writes: << I see that others have noted the 4.3 injectors as the source of the lean condition. By the way, the color code for the 4.3 is Yellow/Blue. As to bore size, I have other throttle bodies with the same size bores as in my 93 PU 4.3. According to the Production Numbers on the others they are for 5.0 and 5.7. I have also been told by others that they all have the same bore size. >> I'm gonna take everybody's word on the injector size thing.... although I am still a little confused. It seemed to me that since a 4.3 is really a V6 version of a 5.7 (same size cylinders) and the V8 computer throws in 2 extra pulses, the injector size would be similar. Oops! Thanks for the advice! Bill K ------------------------------ From: "Robert W. Hughes" Date: Sun, 07 Feb 1999 11:04:52 -0600 Subject: Re: Digital: fuel pressure gage; boost gage > > Is it possible to use the pressure sensing device in a digital scale to > > build such things as an electronic fuel pressure gage, or an electronic > > boost gage, or a boost control? > > My guess is that a scale uses a strain gauge of some sort. To use it > as a pressure sensor you'd have to have some kind of A/B diaphragm > arrangement. Can be done, but ick. > I took one of these bathroom scales apart one time. It was a plain old spring balance with a round disc where the readout scale disc would have been. This disc had a series of lines printed around the outer edge and ran through a LED-sensor assembly. The display driver just counted the lines going by as the disc rotated due to a load. Real cheap, simple, but not much use as a pressure gauge. - -- Robert W. Hughes (Bob) BackYard Engineering Houston, Texas rwhughe@xxx.org ------------------------------ From: ECMnut@xxx.com Date: Sun, 7 Feb 1999 12:28:11 EST Subject: Re: gmecm list In a message dated 2/6/99 6:43:20 PM Eastern Standard Time, quest100@xxx.net writes: > Ran across some additional ECM # info that I did not find in the original > "gmecm list" so am passing it on. Thanks Bud, now if I can just remember how to upload.. Mike V ------------------------------ From: Clarence Wood Date: Sun, 07 Feb 1999 12:44:14 -0600 Subject: Re: Digital: fuel pressure gage; boost gage At 10:25 PM 2/6/99 EST, you wrote: >In a message dated 2/6/99 7:46:19 PM US Mountain Standard Time, >Don.F.Broadus@xxx.com writes: > ><< Autometer has an > isolated system that uses a rubber > diaphragm to isolate the gas liquid. A gauge on the other side of the > diaphragm is responding to air pressure. So I would see > how much the isolator is and find a pressure transducer and a volt meter. > > Don >> > >I have an 1998 PAW catalog and they list the isolator for $39.95 part >#ato-5280 >rated to 200psi working pressure. > >James > > What is a PAW?? If you have an 800 number please send it to me. Thanks for the info Clarence ------------------------------ From: Clarence Wood Date: Sun, 07 Feb 1999 12:40:43 -0600 Subject: Re: Digital: fuel pressure gage; boost gage How do I get a Motorola catalogue? Do they have a 1-800 number? If you do get something that will work, please send me the part number. Clarence At 02:48 AM 2/7/99 -0500, you wrote: >At 05:00 PM 2/6/99 -0600, Clarence Wood wrote: > >> Is it possible to use the pressure sensing device in a digital scale to >> build such things as an electronic fuel pressure gage, or an electronic >> boost gage, or a boost control? > >My guess is that a scale uses a strain gauge of some sort. To use it >as a pressure sensor you'd have to have some kind of A/B diaphragm >arrangement. Can be done, but ick. > >If you want to measure *air* pressure you have lots of choices. Grab >yer Digikey catalog and look up "pressure sensors". Or my own personal >faves, Motorola's MPX line, which are oodles cheaper. If you need >to measure water/fuel/oil pressure, Digikey is still yer buddy, they >have stainless steel units in pipe thread packages. Think oil pressure >sender, I guess. I could use one of these as my fuel pressure sensor, >but I'm an effin' cheap bastard and they're like $80-$200 depending. >The Motorola air-only units are like ~$15, the new automotive >specialty ones that Tom mentioned are, uhh, did anyone see a part >number or a price? I'm desperate tho, and Moto likes me so I'll >try to call Monday and bum a few offa them. > > Hope this helps, > Chris C. > > ------------------------------ From: "Bruce Plecan" Date: Sun, 7 Feb 1999 15:44:36 -0500 Subject: Re: A little too simple - -----Original Message----- From: Onebil2mny@xxx.com> To: diy_efi@xxx.edu> Date: Sunday, February 07, 1999 11:32 AM Subject: Re: A little too simple > As to bore size, I have other throttle bodies with the same size bores as in > my 93 PU 4.3. According to the Production Numbers on the others they are > for 5.0 and 5.7. I have also been told by others that > they all have the same bore size. >> Yes, and the Big Blocks are 2" bore. > >I'm gonna take everybody's word on the injector size thing.... although I am >still a little confused. It seemed to me that since a 4.3 is really a V6 >version of a 5.7 (same size cylinders) and the V8 computer throws in 2 extra >pulses, the injector size would be similar. Oops! The injectors flow requirement is a function of how much HP the engine makes. They all generally run at 80% at WOT (oem applications). This being a observed figure, on a limited number of bins that I have run WOT on my ecm bench. The total flow is what counts. ie 5.7 Orn/Blks are 55#/hr 5.7 Yel/Brwn are 65 Late model Big Block 80 Early Big Block 90 Bruce > >Thanks for the advice! > >Bill K > ------------------------------ From: "Clarence L.Snyder" Date: Sun, 07 Feb 1999 15:44:08 -0500 Subject: Re: fusible link questions Raymond C Drouillard wrote: > > >What is the current in and voltage across the field windings necessary > to > >generate the power proposed? I'm willing to bet that it isn't that huge. > >Certainly the full power output proposed by the original poster will not > be > >dissapated in the field windings. > > > >I've no idea what current is normally presant in the field windings, but > I > >wouldn't expect it to be large, and I would expect that it could be > increased > >significantly before you have problems with overheating. > > I hadn't even considered the power dissapated by the field coil. It > should be small compared to the power dissapated by the rest of the > system. If not, it can be replaced with a ceramic or rare earth > permenent magnet. > > > > >The other issue noone has mentioned is the voltage output, can the > diodes and > >other components survive the high voltage? > > I didn't mention it, but my plan is actually to remove the diodes when I > remove the regulater, and bring three or four wires (depending on if I go > with Y or Delta) out and mounting the rectifiers and switching regulater > in a friendlier location. I would use rectifiers with the appropriate > ratings. > > Ray Drouillard > > > > >-- > >Tom Parker - tparker@xxx.nz > > - http://www.geocities.com/MotorCity/Track/8381/ > > > > > > ___________________________________________________________________ > You don't need to buy Internet access to use free Internet e-mail. > Get completely free e-mail from Juno at http://www.juno.com/getjuno.html > or call Juno at (800) 654-JUNO [654-5866] Just get an old leace-neville alternator (were used a lot on cruisers and taxi-cabs, as well as some trucks) that had external diode packs to start with - makes the job a lor easier. - most were 1500 watt or better. ------------------------------ From: "Clarence L.Snyder" Date: Sun, 07 Feb 1999 16:04:32 -0500 Subject: Re: fusible link questions Raymond C Drouillard wrote: > > >What is the current in and voltage across the field windings necessary > to > >generate the power proposed? I'm willing to bet that it isn't that huge. > >Certainly the full power output proposed by the original poster will not > be > >dissapated in the field windings. > > > >I've no idea what current is normally presant in the field windings, but > I > >wouldn't expect it to be large, and I would expect that it could be > increased > >significantly before you have problems with overheating. Standard early Delcotron fiels was 1.8 to 2.3 amps on 45 amp, 2.8 to 3.2 on 60 amp units. The early Ford alternator field drew 3 amps +/-. This is 36 watts nominal dissipation. This is a small amount of current - and power loss - but on many of the compact alternators tody, running them at close to capacity for any length of time (shorted battery, for instance) will fry the alternator - feilds or stator, or both. > > I hadn't even considered the power dissapated by the field coil. It > should be small compared to the power dissapated by the rest of the > system. If not, it can be replaced with a ceramic or rare earth > permenent magnet. > Which would produce a non-regulatable device. You would then require an active regulator to dissipate the extra power produced externally. > > > >The other issue noone has mentioned is the voltage output, can the > diodes and > >other components survive the high voltage? > Most good alternator diodes are rated at 300PIV. If the diodes have a .6 volt forward drop, at 100 amps they are dissipating 60 watts each. In 3 Phase, they share the load, so likely see closer to 35-40 amp peaks, and 33 amp average for 20 watts per diode, or 200 watts? total diode dissipation at full load. This does not change with voltage, but does with load. Even if the load is split between the two diodes of each pair, that would be 100 watts total diode dissipation - a good reason to have fins and a fan. This dissipation is an order of magnitude higher than the field or stator losses. > I didn't mention it, but my plan is actually to remove the diodes when I > remove the regulater, and bring three or four wires (depending on if I go > with Y or Delta) out and mounting the rectifiers and switching regulater > in a friendlier location. I would use rectifiers with the appropriate > ratings. > > Ray Drouillard > > > > >-- > >Tom Parker - tparker@xxx.nz > > - http://www.geocities.com/MotorCity/Track/8381/ > > > > > > ___________________________________________________________________ > You don't need to buy Internet access to use free Internet e-mail. > Get completely free e-mail from Juno at http://www.juno.com/getjuno.html > or call Juno at (800) 654-JUNO [654-5866] ------------------------------ From: "Quested, Simon" Date: Mon, 08 Feb 1999 10:55:45 +1300 Subject: WTD: Info on a Rotomaster/rayjay turbo Hi All I have picked up a Rotomater/Rayjay turbo and I'm trying to find out what it is. There is a tag on the side with.... Serial No. : 2D2066 Model No. : 3AA1FF60B1 Part No. : 600585 -04 It looks like a Garrett T04.... I'm wondering if the 04 at the end of the part number means anything as I heard that rotomaster got brought/turned into garrett. The compressor wheel has a 70mm diameter it's, 20mm high. Cheers Simon +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Simon Quested (E-mail questeds@xxx.nz) Computer Engineer, Silicon Graphics & Windows NT Support Computing and Educational Resources LINCOLN UNIVERSITY OF NEW ZEALAND Phone (64)(03) 3252811 Ext. 8087 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ http://www.lincoln.ac.nz/ccb/techs/simon/default.htm +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Out of my mind. Back in five minutes. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ------------------------------ From: bearbvd@xxx.net (Greg Hermann) Date: Sun, 7 Feb 1999 15:44:29 -0700 Subject: Re: fusible link questions but on many of the >compact alternators tody, running them at close to capacity for any >length of time (shorted battery, for instance) will fry the alternator - >feilds or stator, or both. Reasons why I think Leece-Neville's are worth the money!! Ditto on the bearings!! If not, it can be replaced with a ceramic or rare earth >> permenent magnet. >> >Which would produce a non-regulatable device. You would then require an >active regulator to dissipate the extra power produced externally. So just rewind the rotor (field) with more turns and higher grade insulation (Class F, or even Class H if necessary) on the wire ! You COULD use smaller gauge wire, so as to make more turns fit onto the existing stator, cuz you ARE gonna have more volts available to push the required current through the field coil. Ampere turns is what excites the stator to a given level of voltage output at any given speed!! Regards, Greg ------------------------------ From: Alain Toussaint Date: Sun, 7 Feb 1999 18:04:32 -0500 (EST) Subject: Re: Digital: fuel pressure gage; boost gage > What is a PAW?? If you have an 800 number please send it to me. > Thanks for the info Performance Automotive Warehouse (or something like that),i don't have any number for them. > Clarence > > Alain Toussaint Drummondville Quebec,Canada alaint@xxx.ca ------------------------------ From: Justin Guest Date: Sun, 7 Feb 1999 23:41:01 +0000 Subject: Re: fusible link questions This could be quite useful if you controlled it properly. A lot of people spend a lot of money trying to increase 12v up to something useful for ICE. Does anyone know how to get an alternator to deliver higher voltages. I was looking at this sort of design with two alternators in mind one running at 12v and the other at a higher voltage. Its a long time since I did my HNC and I was not really interested in generators and alternators at the time. Sorry this is not about EFI but it is electronics. Regards Justin Guest Email as header or jg55776@xxx.uk Phone +44 (0) 1229 482549 >On Thu, 4 Feb 1999, Steve Sassine wrote: SNIP > >Canadain tire used to sell a box that would output 120 vdc from the >alternator. it just full fielded the alt and at around 1500 rpm 120 v > >scarry eh > SNIP ------------------------------ From: Steve Sassine Date: Mon, 8 Feb 1999 11:42:36 +1100 (EST) Subject: Re: fusible link questions On Sun, 7 Feb 1999, Justin Guest wrote: > This could be quite useful if you controlled it properly. A lot of people > spend a lot of money trying to increase 12v up to something useful for > ICE. Does anyone know how to get an alternator to deliver higher > voltages. I was looking at this sort of design with two alternators in > mind one running at 12v and the other at a higher voltage. Its a long > time since I did my HNC and I was not really interested in generators and > alternators at the time. > > Sorry this is not about EFI but it is electronics. > > > Regards Justin Guest > Email as header or jg55776@xxx.uk > Phone +44 (0) 1229 482549 > > > >On Thu, 4 Feb 1999, Steve Sassine wrote: > SNIP > > > >Canadain tire used to sell a box that would output 120 vdc from the > >alternator. it just full fielded the alt and at around 1500 rpm 120 v > > > >scarry eh > > > SNIP > It is not vary hard to also get 120 v ac at 50-60 hz. Remember that most alternators are three phase sync motors. The Three phase output voltage is rectified using a full wave bridge rectifier. This low voltage output, say is is at 12v RMS, can be stepped up using a step up transformer. You only need to by-pass the bridge rectifier. Also need to check the sine wave for different higher order harmonics. This set up can also regulate the ouput voltage. from steve sassine ------------------------------ From: Daniel Ciobota Date: Sun, 07 Feb 1999 18:27:17 -0600 Subject: Re: Digital: fuel pressure gage; boost gage I had an autometer isolator and gauge for my mustang, and it was a diaphragm type, but it used an antifreeze/water mixture at the gauge end, not air. The worst problem with those units is that they're a pain to fill and are prone to leaking. Cyberdyne, advertised in Jegs or Summit catalogs (not sure which), sells a complete kit that includes an electric sender and a digital gauge (0-100psi). Last I checked it sold for about $80 for the complete kit. Autometer just came out with its own electric sender and analog electrical gauge kit, but its more, like $150 for the kit. BTW, the #5280 isolator has just been discontinued by autometer, due to leakage problems. There is a new # on the market that replaces it (#5281?). Boost/vacuum gauges are either analog (-40/+30psi), or digital type (can't remember off hand what brand). There is no isolator for those, as they're usually plumbed to an existing vacuum line or hooked to the "dry" part of the intake. Daniel JRECPA@xxx.com wrote: > In a message dated 2/6/99 7:46:19 PM US Mountain Standard Time, > Don.F.Broadus@xxx.com writes: > > << Autometer has an > isolated system that uses a rubber > diaphragm to isolate the gas liquid. A gauge on the other side of the > > diaphragm is responding to air pressure. So I would see > how much the isolator is and find a pressure transducer and a volt > meter. > > Don >> > > I have an 1998 PAW catalog and they list the isolator for $39.95 part > > #ato-5280 > rated to 200psi working pressure. > > James ------------------------------ From: ECMnut@xxx.com Date: Sun, 7 Feb 1999 20:34:23 EST Subject: Re: WTD: Info on a Rotomaster/rayjay turbo Hi Simon, turbo city has the books to identify that turbo... Seems like ya have to get the right person on the phone. They used to have a rajay ad in Hot Rod or CarCraft for years. Is Joe Boucher out there? He might know who to talk to over there. HTH Mike V. > I have picked up a Rotomater/Rayjay turbo and I'm trying to find out > what it is. > There is a tag on the side with.... > Serial No. : 2D2066 > Model No. : 3AA1FF60B1 > Part No. : 600585 -04 ------------------------------ From: KD6JDJ@xxx.com Date: Sun, 7 Feb 1999 20:46:27 EST Subject: Re: fusible link questions >I've no idea what current is normally presant in the field windings, but I >wouldn't expect it to be large, and I would expect that it could be increased >significantly before you have problems with overheating. IIRC, .4 or .6 amp neighborhood. Besides, just spin it a bit faster with the same field current, and you will have higher voltage. You would only need the higher field (rotor) current in order to get the output voltage up at lower rpm. Regards, Greg Greg When your message got to my computer terminal it read .4 or .6 amp. I want to be sure that the interested readers realize that conventional automotive alternator rotors will draw a current of -- from 2 to 10 amps when connected to a 12vdc source, depending upon the size and manufacturer. I understand that cooling is a problem that is given consideration when high currents are drawn by rotors. And the use of greater numbers of turns (to minimize the current) introduces inductance, which complicates the regulator design. I have rewound both rotors and stators in Delco alternators, trying to make special 'stuff'. Nothing that I have made has ever been worth bragging about. I may have some information that would be helpful to thoes of you who are beginning a project , and dont have it ALL figured out. Jerry Jerry ------------------------------ From: "Clarence L.Snyder" Date: Sun, 07 Feb 1999 21:35:06 -0500 Subject: Re: fusible link questions Steve Sassine wrote: > > On Sun, 7 Feb 1999, Justin Guest wrote: > > > This could be quite useful if you controlled it properly. A lot of people > > spend a lot of money trying to increase 12v up to something useful for > > ICE. Does anyone know how to get an alternator to deliver higher > > voltages. I was looking at this sort of design with two alternators in > > mind one running at 12v and the other at a higher voltage. Its a long > > time since I did my HNC and I was not really interested in generators and > > alternators at the time. > > > > Sorry this is not about EFI but it is electronics. > > > > > > Regards Justin Guest > > Email as header or jg55776@xxx.uk > > Phone +44 (0) 1229 482549 > > > > > > >On Thu, 4 Feb 1999, Steve Sassine wrote: > > SNIP > > > > > >Canadain tire used to sell a box that would output 120 vdc from the > > >alternator. it just full fielded the alt and at around 1500 rpm 120 v > > > > > >scarry eh > > > > > SNIP > > > > It is not vary hard to also get 120 v ac at 50-60 hz. Remember that > most alternators are three phase sync motors. The Three phase output > voltage is rectified using a full wave bridge rectifier. This low voltage > output, say is is at 12v RMS, can be stepped up using a step up > transformer. You only need to by-pass the bridge rectifier. Also need to > check the sine wave for different higher order harmonics. This set up can > also regulate the ouput voltage. > > from steve sassine If you get 60CPS at 1000 alternator RPM, I'm sorry to have to tell you you won't get much output from it. The faster you spin it, the more output you get. Usually "geared" about 3:1 to the engine, at 2000 RPM coasting down the highway you are spinning the alt at about 6000 rpm, and producing 3 phase AC at360 cps. The 400CPS previously mentioned is AWFULL close to what you will see at highway speeds. If you want AC from an automotive alternator, just get a decent inverter.Spikes of current draw are buffered by your battery so you don't fry the alt, frequency is steady, as is voltage. You will likely pick up the inverter for less than it costs to convert the alternator to a useless piece of junk, assuming you value your time at anything over about 50 cents an hour. I snagged a 1500 va unit from an old Bell Telephone truck for $75 canadian dollars. That's about 50 US Greenbacks. ------------------------------ From: Tom Sharpe Date: Sun, 07 Feb 1999 21:20:58 -0600 Subject: Re: WTD: Info on a Rotomaster/rayjay turbo My guess is that if it's a T04B, The 3A is the compressor housing, A1 is the compressor trim, 60 is the turbin A/R ratio, and B1 is the turbin trim. But that's a guess from a long time ago. Tom Quested, Simon wrote: > Hi All > > I have picked up a Rotomater/Rayjay turbo and I'm trying to find out > what it is. > There is a tag on the side with.... > Serial No. : 2D2066 > Model No. : 3AA1FF60B1 > Part No. : 600585 -04 > > It looks like a Garrett T04.... I'm wondering if the 04 at the end of > the part number means anything as I heard that rotomaster got > brought/turned into garrett. > > The compressor wheel has a 70mm diameter it's, 20mm high. > > Cheers ------------------------------ From: "Brian Franchuk" Date: Sun, 7 Feb 1999 21:31:33 0000 Subject: Looking for specs for a GM MAF I went out to the junk yard today and found a MAF out of a late 80's buick, part number 25007770. Does anyone have any info on this sensor or where I can look up GM sensors? I was able to hook it up and get the frequency output working, but I would like to know how to translate the frequency to a mass flow rate. Will this MAF be able to handle a 220HP 3.4 liter engine or do I need something bigger. Thanks Brian Franchuk ------------------------------ From: Jim Davies Date: Sun, 7 Feb 1999 19:49:02 -0800 (PST) Subject: Re: fusible link questions On Sun, 7 Feb 1999, Justin Guest wrote: > This could be quite useful if you controlled it properly. A lot of people > spend a lot of money trying to increase 12v up to something useful for > ICE. Does anyone know how to get an alternator to deliver higher > voltages. I was looking at this sort of design with two alternators in > mind one running at 12v and the other at a higher voltage. Its a long > time since I did my HNC and I was not really interested in generators and > alternators at the time. > Ford powerstroke diesels use 120 volts for the injectors, so it might be a place to look... ------------------------------ From: "David A. Cooley" Date: Sun, 07 Feb 1999 22:56:54 -0500 Subject: Re: fusible link questions At 07:49 PM 2/7/99 -0800, you wrote: > >> >Ford powerstroke diesels use 120 volts for the injectors, so it might be a >place to look... I haven't looked at the fords specifically, but Diesels, because they run 34,000PSI at the injectors use mechanical injection. The fuel pump is like a distributor and gives a high pressure shot to the line going to the injector to force it open. =========================================================== David Cooley N5XMT Internet: N5XMT@xxx.net Packet: N5XMT@xxx. Member #7068 I am Pentium of Borg...division is futile...you will be approximated. =========================================================== ------------------------------ From: steve ravet Date: Sun, 07 Feb 1999 22:11:59 +0000 Subject: Re: Looking for specs for a GM MAF I know a MAF table has been posted in the past, but I was unable to locate it in the archives. Try digging around in there... - --steve Brian Franchuk wrote: > > I went out to the junk yard today and found a MAF out of a late 80's > buick, part number 25007770. Does anyone have any info on this > sensor or where I can look up GM sensors? I was able to hook it up > and get the frequency output working, but I would like to know how to > translate the frequency to a mass flow rate. Will this MAF be able > to handle a 220HP 3.4 liter engine or do I need something bigger. > > Thanks > > Brian Franchuk - -- Steve Ravet ARM, INC steve.ravet@xxx.com www.arm.com ------------------------------ From: "Bruce Plecan" Date: Sun, 7 Feb 1999 23:36:25 -0500 Subject: Re: Looking for specs for a GM MAF - -----Original Message----- To: diy_efi@xxx.edu> Date: Sunday, February 07, 1999 11:24 PM Subject: Re: Looking for specs for a GM MAF All I can offer is the specs on a GN/Ttype and they are 27-147Hz 4.6-4.6v 50% duty cycle. Those are nembers I've gathered but not actually tested. The calibration will change depending on sensor. Bruce I went out to the junk yard today and found a MAF out of a late 80's buick, part number 25007770. Does anyone have any info on this sensor or where I can look up GM sensors? I was able to hook it up and get the frequency output working, but I would like to know how to translate the frequency to a mass flow rate. Will this MAF be able to handle a 220HP 3.4 liter engine or do I need something bigger. Thanks Brian Franchuk ------------------------------ From: Ervinc90@xxx.com Date: Mon, 8 Feb 1999 00:16:03 EST Subject: Newbie ALDL question I have been reading the archives on aldl for about a month or so. I went ahead and built the ALDL interface that was posted which contained: a max232 chip 9 resistors, 4 diodes, 6 capacitors and a voltage regulator. I have downloaded the gcar2.exe and the pcmcomm program. My question is this: Why am I not receiving continuous data in the monitor mode with the gcar2 program on a 386 with dos 6.2? I have gotten spurts of data while checking for the connection with the ecm and noticed that everytime I turn the ignition on and off a set of 00 appear on the computer. ( this leads me to believe that the max 232 chip is seeing something??) I have double checked the circuit several times and even rebuilt a second from scratch. I have tried this on a 91 corvette (ecm: 1227727) and a 95 chev c1500 (don't recall the computer). I also noticed another interface diagram which utilized a 74ls07 instead of the transistors and resistors. Is this somthing worth trying? I am a metallurgical engineer that knows a little about circuits, but not enough to figure the problem out. Thanks, Bill Carson ------------------------------ From: Raymond C Drouillard Date: Sun, 7 Feb 1999 01:11:16 -0500 Subject: Re: fusible link questions eilds or stator, or both. >> >> I hadn't even considered the power dissapated by the field coil. It >> should be small compared to the power dissapated by the rest of the >> system. If not, it can be replaced with a ceramic or rare earth >> permenent magnet. >> >Which would produce a non-regulatable device. You would then require an >active regulator to dissipate the extra power produced externally. That's the point of the whold discussion. I would run the alternater at a higher voltage and use an efficient switching regulater to step it down. Much like a transformer, a switching regulater will step up the current when it steps down the voltage. A switching regulater does not regulate by dissapating the extra power. >Most good alternator diodes are rated at 300PIV. >If the diodes have a .6 volt forward drop, at 100 amps they are >dissipating 60 watts each. In 3 Phase, they share the load, so likely >see closer to 35-40 amp peaks, and 33 amp average for 20 watts per >diode, or 200 watts? total diode dissipation at full load. This does not >change with voltage, but does with load. Even if the load is split >between the two diodes of each pair, that would be 100 watts total diode >dissipation - a good reason to have fins and a fan. This dissipation is >an order of magnitude higher than the field or stator losses. I discussed this very thing with one of my electronics professors. Yes, silicon diodes drop 0.6 or 0.7 volts normally. The diodes in an automotive alternater, however, will drop more like 2V under heavy load. An automotive alternater is wired in delta, and uses six diodes to rectify the output. The current from any coil will go through two diodes in its path through the load. That gives us a total voltage drop of 4V. Since we're supplying around 14V, the diodes dissapate about 28% of the total output. This means that if the alternater is providing 1000 watts to the load, it is dissapating an additional 280 watts in the diodes. The stator windings are dissapating some power, too. Ray Drouillard ___________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com/getjuno.html or call Juno at (800) 654-JUNO [654-5866] ------------------------------ From: Jim Davies Date: Sun, 7 Feb 1999 22:30:01 -0800 (PST) Subject: Re: fusible link questions On Sun, 7 Feb 1999, David A. Cooley wrote: > At 07:49 PM 2/7/99 -0800, you wrote: > > > > >> > >Ford powerstroke diesels use 120 volts for the injectors, so it might be a > >place to look... > > I haven't looked at the fords specifically, but Diesels, because they run > 34,000PSI at the injectors use mechanical injection. The fuel pump is like > a distributor and gives a high pressure shot to the line going to the > injector to force it open. The 7.3 powerstroke diesel uses electronic fuel injection. The injectors are 110 volts with a variable oil pressure boost controlled by the ECU. ------------------------------ From: dzorde@xxx.com (dzorde) Date: Mon, 8 Feb 1999 00:16:26 -0800 (PST) Subject: RE:Digital fuel pressure gauge Anyone thought of looking at the el-cheapo digital tyre gauges, they use a semiconductor sensor and should be good for up to around 200PSI. You'd just need to work out some way of attaching the unit with a screw thread or barb end. Dan dzorde@xxx.au - -----Original Message----- From: Daniel Ciobota [SMTP:dciobota@xxx.net] Sent: Monday, February 08, 1999 8:27 AM To: diy_efi@xxx.edu Subject: Re: Digital: fuel pressure gage; boost gage I had an autometer isolator and gauge for my mustang, and it was a diaphragm type, but it used an antifreeze/water mixture at the gauge end, not air. The worst problem with those units is that they're a pain to fill and are prone to leaking. Cyberdyne, advertised in Jegs or Summit catalogs (not sure which), sells a complete kit that includes an electric sender and a digital gauge (0-100psi). Last I checked it sold for about $80 for the complete kit. Autometer just came out with its own electric sender and analog electrical gauge kit, but its more, like $150 for the kit. BTW, the #5280 isolator has just been discontinued by autometer, due to leakage problems. There is a new # on the market that replaces it (#5281?). Boost/vacuum gauges are either analog (-40/+30psi), or digital type (can't remember off hand what brand). There is no isolator for those, as they're usually plumbed to an existing vacuum line or hooked to the "dry" part of the intake. Daniel ------------------------------ End of DIY_EFI Digest V4 #96 **************************** 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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