DIY_EFI Digest Thursday, 18 March 1999 Volume 04 : Number 179 In this issue: Re: DIY_EFI Digest V4 #162 Re: Frederic Breitwieser/turbo discussion Re: DIY_EFI Digest V4 #162 RE: Bosch Fuel Pump e-prom? Re: Holley 4tbi to 7747 Re: e-prom? Re: Holley 4tbi to 7747 Knocksensing with HIP 9010 Re: Knocksensing with HIP 9010 Re: Fuel Pump Re: Shift light Re: Bosch Fuel Pump Re: Fuel tuning... Conversion to EFI : Fuel system diy_efi projects Re: Conversion to EFI : Fuel system Off Panhard Bar Re: Conversion to EFI : Fuel system Re: Conversion to EFI : Fuel system Re: Shift light Re: Off Panhard Bar See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: Glen Beard Date: Thu, 18 Mar 1999 06:16:53 -0500 Subject: Re: DIY_EFI Digest V4 #162 Bruce Plecan wrote: > I got an idea, this will sound easy but will take some work to dial in. > Take the Distributor apart and get a second shutter disc. Notice how they > have a set of > 4 matching slots, and 4 oblong holes at one radius from the center. Take > the second disc, > and redrill it so that when you hold it up to the light you have 8 small > holes on the one pattern. > Then use a regular 7 pin ecm module. Fab a little kludge to read the 8 holes > as the normal reluctor/pickup would and then feed that to the module, then > wire the module as you would normally to a say 1227730. Then the rest is a > plug and play for the harness/sensors. > One LT1 driven by a 730 thank you The LT1 Optispark(distributor) already has a slotted disc in it. There are high and low resolution slots. The high res has 360 slots and the low res has 4 long and 4 short slots. If you are going to 'fabricate a little kludge', wouldn't it be easier to just use the existing hardware? An led/light sensor pick up the slots. Then you could take the output (which would already be digital) and convert it from 360 to 8 pulses for the input into the older computer. There is a pic of the disc in the optispark here. http://www.charm.net/~mchaney/optisprk/optisprk.htm - -- Glen Beard 95 T/A conv M6 Vortech !heads, !cam http://home.nycap.rr.com/gbeard1/TransAm.html ------------------------------ From: Frederic Breitwieser Date: Thu, 18 Mar 1999 12:36:03 +0000 Subject: Re: Frederic Breitwieser/turbo discussion > I've heard that noise and it's like fingernails on the blackboard at mach 4. Tom That's a pretty close description. I heard it over the open headers (well, open post turbo anyway) at 6000 RPM. Very loud. - -- Frederic Breitwieser Bridgeport, CT 06606 http://www.xephic.dynip.com 1993 Superchaged Lincoln Continental 1989 500cid Turbocharged HWMMV 1975 Dodge D200 Club Cab (soon to be twin turbo 440) 2000 Buick GTP (twin turbo V6) ------------------------------ From: "Bruce Plecan" Date: Thu, 18 Mar 1999 08:11:07 -0500 Subject: Re: DIY_EFI Digest V4 #162 - -----Original Message----- From: Glen Beard To: diy_efi@xxx.edu> Date: Thursday, March 18, 1999 6:36 AM Subject: Re: DIY_EFI Digest V4 #162 >Bruce Plecan wrote: > >> I got an idea, this will sound easy but will take some work to dial in. >> Take the Distributor apart and get a second shutter disc. Notice how they >> have a set of >> 4 matching slots, and 4 oblong holes at one radius from the center. Take >> the second disc, >> and redrill it so that when you hold it up to the light you have 8 small >> holes on the one pattern. >> Then use a regular 7 pin ecm module. Fab a little kludge to read the 8 holes >> as the normal reluctor/pickup would and then feed that to the module, then >> wire the module as you would normally to a say 1227730. Then the rest is a >> plug and play for the harness/sensors. >> One LT1 driven by a 730 thank you > >The LT1 Optispark(distributor) already has a slotted disc in it. There are high >and low resolution slots. The high res has 360 slots and the low res has 4 long >and 4 short slots. If you are going to 'fabricate a little kludge', wouldn't it >be easier to just use the existing hardware? Reread what I said... I am. An led/light sensor pick up the >slots. Then you could take the output (which would already be digital) and >convert it from 360 to 8 pulses for the input into the older computer. If you start with the high resolution 360 then you have to develope a start point.. All the electonics for reading the hi+low are in the ecm. > >There is a pic of the disc in the optispark here. > http://www.charm.net/~mchaney/optisprk/optisprk.htm > >-- >Glen Beard >95 T/A conv M6 Vortech !heads, !cam >http://home.nycap.rr.com/gbeard1/TransAm.html > > ------------------------------ From: "Kurek, Larry" Date: Thu, 18 Mar 1999 09:45:14 -0600 Subject: RE: Bosch Fuel Pump No, I am having problems getting cross references on USA Bosch pumps. I have a 9 580 233 003 (where the 9 signifies US, and a 0 would signify Import, I have been told), and NOBODY can find a listing for it. I'm trying to work through Bosch USA, but haven't heard back from them yet... Larry > > I called my local parts dealer and they cna't find a listing > for a Bosch 9 > 580 810 020? Is this the total number or am I missing some > nomenclature? > > Mike Pilkenton > -----Original Message----- > From: Clarence Wood > To: diy_efi@xxx.edu > > Date: Friday, March 12, 1999 4:48 PM > Subject: RE: Bosch Fuel Pump > > > > It is external and it has a threaded inlet, I am assuming > that the end > where the plus and neg. terminals are is the inlet, but the > outlet is not > threaded. Also, by threaded I assume you mean that the inlet > tube can be > removed. > > Anyway, if this is the pump you were looking for it can be found at > Sherco Auto Supply, 1-800-548-6229, ask to speak to Mark. The pump is > packaged as a Carter, #P74099. It is supposed to be 90psi, > 38gph. Comes > with a padded mounting bracket. Mark told me that it is a > secondary pump > for a Ford; he didn't know what model of Ford. > >>> > >>> > >>> Can anybody help me find out anything about this pump: > >>> > >>> Bosch: 9 580 810 020 > >>> 12V. 562-10 > >>> E7TF.9350.AA 5B10 > >>> > >>> Thanks > >>> Clarence > >>> > > ------------------------------ From: esc Date: Thu, 18 Mar 1999 10:11:03 -0600 Subject: e-prom? Re: Holley 4tbi to 7747 I want to do this also. That eprom sure would help a lot... At 06:33 AM 3/15/99 -0800, you wrote: >Well i happen to know how they get a 7730 hooked up to the 4bbl TBI. >I also happen to have an eprom from just such a combination! > >Andy > > >---cwagner@xxx.net wrote: >> >> Here is probably a simple question, but here we go. How would a >> person go about adapting a Holley 4 barrel throttle body >> injection(just the throttle body) to a 7747 computer? Would the >> computer be enough to run the four injectors? I know Howell does >> something like this but want to do it my self. >> > >_________________________________________________________ >DO YOU YAHOO!? >Get your free @xxx.com > Eric Comstock esc@xxx.com ------------------------------ From: andy quaas Date: Thu, 18 Mar 1999 12:02:07 -0800 (PST) Subject: Re: e-prom? Re: Holley 4tbi to 7747 well i've gotta find time this weekend to read it. Andy - ---esc wrote: > > I want to do this also. That eprom sure would help a lot... > > > At 06:33 AM 3/15/99 -0800, you wrote: > >Well i happen to know how they get a 7730 hooked up to the 4bbl TBI. > >I also happen to have an eprom from just such a combination! > > > >Andy > > > > > >---cwagner@xxx.net wrote: > >> > >> Here is probably a simple question, but here we go. How would a > >> person go about adapting a Holley 4 barrel throttle body > >> injection(just the throttle body) to a 7747 computer? Would the > >> computer be enough to run the four injectors? I know Howell does > >> something like this but want to do it my self. > >> > > > >_________________________________________________________ > >DO YOU YAHOO!? > >Get your free @xxx.com > > > Eric Comstock > esc@xxx.com > _________________________________________________________ DO YOU YAHOO!? Get your free @xxx.com ------------------------------ From: "Nils Björkman" Date: Thu, 18 Mar 1999 21:08:03 +0100 Subject: Knocksensing with HIP 9010 Hi Im going to design my own efi based on an PIC 16C74A microcontroller. I am going to use the Harries HIP 9010 Knock sensor circuit for feedback of air/fuel mixture. I have downloaded all schamatics, datasheets and other I hav found, but not find any information about suitable components (resistors and capacitors) around the circuit. How do I know that the circuit works, and how should I test my circuit to be sertain that it doesn´t miss any knocks. If I´m justy beleaving that the sensor works and it doesn´t my wngine will probably be no more pretty soon. What output should I look for, values for R1-R4, program parameters etc. are still a mystery for me. My engine is a Volvo B23 (2.3 liter) 4 cylinder, Liqid cooled, Cast iron block and aluminium head, converted for use in boat, liquidcooled exhaust, max rpm aprox 6000 rpm, unleaded 95 octan fuel. Does anybody have information so pleas let me know, my project is on hold till I knnow how to do with knocksensing. Thanks Nils ------------------------------ From: Mike Morrin Date: Fri, 19 Mar 1999 09:55:09 +1300 Subject: Re: Knocksensing with HIP 9010 At 09:08 pm 18/03/99 +0100, Nils Björkman wrote: >Hi > >Im going to design my own efi based on an PIC 16C74A microcontroller. > >I am going to use the Harries HIP 9010 Knock sensor circuit for feedback >of air/fuel mixture. I think you have got the wrong end of stick. A knock sensor is used for feedback of ignition timing. An oxygen sensor in the exhaust is used for mixture feedback. It also seems to be highly desirable that your efi system has reasonably accurate open-loop control of the system, as the real world knock and ego sensors are far from ideal (in range of operation and speed of response). regards, Mike ------------------------------ From: rr Date: Thu, 18 Mar 1999 08:55:16 -0800 Subject: Re: Fuel Pump Yes, you are correct. The difference being that when an inline pump is installed, how often does the pickup/tank get modified with baffling? That's all I was trying to say. (And reading it again, I'll be choosing my words more carefully...) BobR. Mike Pilkenton wrote: > > Why would an in-line pump require a fuel/air separator? Air picup would > come from the tank. It seems to me the style of pump doesn't matter as long > as the tank is designed properly???? > > Mike P. > > -----Original Message----- > From: rr > To: diy_efi@xxx.edu> > Date: Wednesday, March 17, 1999 12:35 PM > Subject: Re: Fuel Pump > > >It is a good way to go, pricey, but good. I understand that they > >build the tank with baffling around the pickup. Check this, as > >this is the major benefit. Witout the baffling, it's not worth > >it, IMHO. > > > >With an inline pump, proper operation will require a fuel/air > >seperator. Otherwise, air pickup causes short leanouts and > >the corresponding problems. > > > >Unless you keep the tank over 1/2 full, can be a short term fix. > > > >BobR. > > > >>Maybe this is the wrong place to ask this, but here goes. > >> > >>I'm going to be swapping a 93 LT1 from my wrecked firebird formula into a > >>'66 Impala. Should I bite the bullet and buy a rock valley in tank pump, > >>its $300 installed. Would an inline pump be a better deal. > >> > >>- Eric > > ------------------------------ From: "Clarence L.Snyder" Date: Thu, 18 Mar 1999 16:33:35 -0500 Subject: Re: Shift light Autometer makes one - available from Summit for $61.50 with amber light and requires "pill kit" to select RPM. Kit is 21.69 per range. ------------------------------ From: Clarence Wood Date: Thu, 18 Mar 1999 13:28:35 -0600 Subject: Re: Bosch Fuel Pump Mike, the only thing I left out was that the box it came in was Parts Plus, therefor the part number P74099 may only be a Parts Plus number. Also, the box had the wrong part number: P74009 which Mark discovered while we were talking about the pump. There is a bar code and a number: 7 24596 57992 1. Below that there is F95335. Also, it was packaged as a Carter Pump. Clarence At 07:32 PM 3/17/99 -0800, you wrote: >I called my local parts dealer and they cna't find a listing for a Bosch 9 >580 810 020? Is this the total number or am I missing some nomenclature? > >Mike Pilkenton >-----Original Message----- >From: Clarence Wood >To: diy_efi@xxx.edu> >Date: Friday, March 12, 1999 4:48 PM >Subject: RE: Bosch Fuel Pump > > >> It is external and it has a threaded inlet, I am assuming that the end >where the plus and neg. terminals are is the inlet, but the outlet is not >threaded. Also, by threaded I assume you mean that the inlet tube can be >removed. >> Anyway, if this is the pump you were looking for it can be found at >Sherco Auto Supply, 1-800-548-6229, ask to speak to Mark. The pump is >packaged as a Carter, #P74099. It is supposed to be 90psi, 38gph. Comes >with a padded mounting bracket. Mark told me that it is a secondary pump >for a Ford; he didn't know what model of Ford. >>>> >>>> >>>> Can anybody help me find out anything about this pump: >>>> >>>> Bosch: 9 580 810 020 >>>> 12V. 562-10 >>>> E7TF.9350.AA 5B10 >>>> >>>> Thanks >>>> Clarence >>>> > > > ------------------------------ From: Clarence Wood Date: Thu, 18 Mar 1999 13:34:18 -0600 Subject: Re: Fuel tuning... I am envious! At 12:46 PM 3/17/99 -0500, you wrote: >Hi Clarence, >Not a stupid question at all. >My PCM outputs knock counts, knock retard and advance through the ALDL. I'm >using a very modified version of the GCAR software (Thanks to Mike Pitts!) >and it all displays on my laptop... > > > >-----Original Message----- >From: Clarence Wood >To: diy_efi@xxx.edu> >Date: Wednesday, March 17, 1999 9:17 AM >Subject: Re: Fuel tuning... > > >> This question may seem stupid, but please don't laugh. How do you >determine degrees advance while you are driving down the road? I couldn't >get anybody to hang over my fender with a timing light; well, I found one >guy but he couldn't remember what he saw. >> > > > > ------------------------------ From: Mitch Date: Thu, 18 Mar 1999 14:01:33 -0800 Subject: Conversion to EFI : Fuel system Folks, I have decided, after recently installing a ZZ4 in my 66 El Camino, that I have purchased my last carburetor; I'm going to EFI. To that end I recently purchased a 91 Camaro with 305 TBI and five speed as a daily driver and to acquaint myself with EFI. I am thinking of purchasing the same engine and transmission combination (pre-93) from a local salvage yard specializing in Camaros and installing it in a 66 Malibu I have which will serve as a mule for EFI work. I reckon it's a lot easier to install this combination in a car designed for Chevy small blocks than to attempt something weird like the Jaguar XJ6 Series I or 240Z (which is what I have planned for later) swap first time. I learn by doing and don't mind working through a few projects to get to what I want eventually. Anyway, after reading Mike Knell's books, as well as Hartman's, I have decided the most challenging aspect of the swaps, for me, will be retro-fitting the fuel systems on mechnical pump cars. Instead of getting custom-made fuel tanks, I'd like to implement the dual-pump external fuel reservoir system described in Knell's TBI/TPI book. I am working this out step by step. To discuss this with you folks and some other buddies, I have put some drawings up at: http://www.employees.org/~ozyman/carstuff/efi_fuel.htm There are a number of vexing issues. 1. Where should the main return line go? Knell's book suggests back to the remote fuel reservoir, but I was concerned about heat. I was thinking that it would be best to return the fuel that has been to the intake manifold back to the large tank. If you return it to the small tank, some of it goes back to the manifold for further heating. If you return it to the large tank, there is no such problem. Now, my guess is it doesn't hurt to do it this way, but I was wondering what the logic is for returning back to the remote reservoir. I asked Knell about this, and he said if you don't return to the reservoir you can suck air if you run out of fuel from the main tank. But if you run out of fuel you run out of fuel; returning to the remote reservoir will maybe give you another minute or so of life. 2. What is the air pressure in the main fuel tank? Is it positive or negative? I am concerned because I thought the charcoal canister works with positive air pressure in the fuel tank, and I don't see how it can be positive in my diagram. I have been assured from several quarters it is about 1-2psi positive, but was looking for an exlpanation of this, since you are always sucking fuel out of the tank. 3. Does it matter whether the pumps are above or below the fuel tank? I was assuming it didn't, but I recently read a book which suggested the pumps should be below the tank. This would be difficult for me to set up in my car. 4. Just some general stuff: I am concerned about noise. One idea I had was to make this an assembly and mount it on rubber mounts, like motor mounts. I was definitely considering some kind of case or cabinet (steel (like an old toolbox) or plastic), but I am concerned about the hazard of buildup of fumes, and also cooling for the pumps. I'd need some way to vent the thing. I wonder whether it would be overkill to build some cooling/venting fans into the cabinet. So if you folks have any advice or ideas on this, please let me know. I'll continue to refine the diagrams as I nail this down. After fooling around with the stock TBI Malibu, I expect to convert the 327 in my garage to TBI or port injection the diy_efi way. Cheers, Mitch Barrie Goat Hill, CA ------------------------------ From: Matt Boland Date: Fri, 19 Mar 1999 09:50:43 +1000 Subject: diy_efi projects Hi All, I'm new to this diy_efi forum, just joined up the other day. I have been designing an efi system based on the Philips 80C552 8 bit microcontroller, sort of 3/4 finished. My problem is that after a day of designing/building circuits, I just wanna watch tv. I was thinking that a distributed effort could yield a world class product, sort of like the open software guys do. You know, they just do their little bit and put in their 2 cents worth and help with the puzzle. Does anybody know of such a project in the efi arena? If so could you let me know? Thanks. Maybe if there is not one going on already, we could start one. All the stuff could be copyrighted to the designer, but freely available for downloading and construction by anyone as long as they don't sell it. You know how it goes. Anyway, let me know what ya' think... - -- Matt Boland m.boland@xxx.au CSIRO Division of Exploration and Mining Phone: +61 7 3212-4482 PO Box 883 Kenmore Fax: +61 7 3212-4455 QLD 4069 Australia ------------------------------ From: "Bruce Plecan" Date: Thu, 18 Mar 1999 19:09:41 -0500 Subject: Re: Conversion to EFI : Fuel system - -----Original Message----- From: Mitch To: diy_efi@xxx.edu>; Date: Thursday, March 18, 1999 5:14 PM Subject: Conversion to EFI : Fuel system The purpose of the JTR book is to tell the first timer how to do, so that it works first time thru. I'd suggest that you do it his way the first time. Get it up and running. Then experiment. Mount pump below gas tank height. Never inclose a fuel pump in a non oem "housing". They make fuel-air bombs. The warm fuel issue really is nothing you'll have much control over. If you min the amount of fuel recycled, all the fuel lines are hotter than need be. In high demand the Hot fuel (in the rails) will be used rather quickly. The fuel in the tank is what it's going to be, based on fuel pump capacity, and how much is recycled. Really not much to do here since the pump needs to be large enough for WOT fuel demand. Follow someones lead and just use their info., first time thru. Just getting the installation "stock" is enough work. You'll have lots of time to try and improve it. IMHO Bruce > >Anyway, after reading Mike Knell's books, as well as Hartman's, I have >decided the most challenging aspect of the swaps, for me, will be >retro-fitting the fuel systems on mechnical pump cars. Instead of getting >custom-made fuel tanks, I'd like to implement the dual-pump external fuel >reservoir system described in Knell's TBI/TPI book. >I am working this out step by step. To discuss this with you folks and >some other buddies, I have put some drawings up at: >There are a number of vexing issues. >1. Where should the main return line go? Knell's book suggests back to the >remote fuel reservoir, but I was concerned about heat. I was thinking that >it would be best to return the fuel that has been to the intake manifold >back to the large tank. If you return it to the small tank, some of it >goes back to the manifold for further heating. If you return it to the >large tank, there is no such problem. >Now, my guess is it doesn't hurt to do it this way, but I was wondering >what the logic is for returning back to the remote reservoir. I asked >Knell about this, and he said if you don't return to the reservoir you can >suck air if you run out of fuel from the main tank. But if you run out of >fuel you run out of fuel; returning to the remote reservoir will maybe give >you another minute or so of life. >2. What is the air pressure in the main fuel tank? Is it positive or >negative? I am concerned because I thought the charcoal canister works >with positive air pressure in the fuel tank, and I don't see how it can be >positive in my diagram. I have been assured from several quarters it is >about 1-2psi positive, but was looking for an exlpanation of this, since >you are always sucking fuel out of the tank. >3. Does it matter whether the pumps are above or below the fuel tank? I >was assuming it didn't, but I recently read a book which suggested the >pumps should be below the tank. This would be difficult for me to set up >in my car. >4. Just some general stuff: I am concerned about noise. One idea I had was >to make this an assembly and mount it on rubber mounts, like motor mounts. >I was definitely considering some kind of case or cabinet (steel (like an >old toolbox) or plastic), but I am concerned about the hazard of buildup of >fumes, and also cooling for the pumps. I'd need some way to vent the >thing. I wonder whether it would be overkill to build some cooling/venting >fans into the cabinet. >So if you folks have any advice or ideas on this, please let me know. I'll >continue to refine the diagrams as I nail this down. After fooling around >with the stock TBI Malibu, I expect to convert the 327 in my garage to TBI >or port injection the diy_efi way. >Cheers, >Mitch Barrie >Goat Hill, CA ------------------------------ From: "H. J. Zivnak" Date: Thu, 18 Mar 1999 18:23:47 -0800 Subject: Off Panhard Bar - ----Original Message----- From: Gary Derian To: diy_efi@xxx.edu> Date: Monday, March 15, 1999 10:33 AM Subject: Re: Off Panhard bar >There was a general discussion of rear suspension design. My point was that >a 4 link, where two of the links are angled to provide lateral location will >bind up when the car leans in a corner. One angled link will pull forward, >the other will push rearward. The amount is small but it is there. With >rubber bushings, it works OK. This type of 4 link is popular on many US >cars, notably GM intermediate and full size and Ford Fox chassis Mustangs >and their siblings. > Wouldn't the upper bars pull/push the same amount if spaced exactly >>>the same distance apart from the center? I need to draw something to >>>understand this better. >No. The binding is not from the change in angle between the rod and the >pivot axis. Its because one link tries to rotate the axle pinion up and the >other tries to rotate the axle pinion down. This occurs only when the body >rolls. > Hello Gary, I was going to send this off list, but in view of the other interest I thought I'd share. Earlier in this thread Greg wrote: "Or go scrounging in a boneyard that has some old Alfas. They used an upper triangle, with two pivot points on the chassis, and a BALL joint attached just to the left side of the pumpkin, plus two lower trailing arms. Particularly if you replaced the chassis pivots of the triangle (rubber stock) with bronze on steel, also if you replaced the lower rod ends with real rod ends, they were as NICE a live rear axle setup as you could want." I believe that this worked, and worked well. The ball joint located the roll center. As the body rolled in a turn, the worst action I can see is that the axle rotated slightly. Most certainly there was not binding, even with rod ends and bronze bushes, in spite of the off center location. Some might even suggest that the roll center would be better placed to the right, since this is the side which unloads under acceleration. I think this demonstrates how much a design can deviate from a theoretical ideal, or how much you sacrifice an ideal in one area chasing the overall performance of a system. When I suggested two angled arms, I saw a virtual triangle with the roll center located where lines projected from the arms intersected the centerline of the axle. In this case we have two rod ends in shear rather than a single ball joint with bending stress. As long as I picture this virtual triangle, I can so no reason for bind. The virtual triangle acts the same as the real one. Also, I don't see any reason not to turn this virtual triangle around so the base is connected to the axle. The virtual apex still determines the roll center, the body will roll about this point, and the axle will still rotate slightly, but still no bind. Now the roll center has a more constant relationship to the center of gravity, and since this relationship determines the amount of body roll, perhaps the car will behave more consistently. As I have said before, ASCII is not an easy medium. It's hard to describe a concept in a concise manner and show a rapier like wit at the same time. :-) Maybe we are not seeing the same picture. I know now that I wasn't when I visualized your description of the torque arm setup from the Vega. To that end I have posted an AutoCad Whip file which contains a drawing of a Satchell Link suspension to incomming, Satchell Link.dwf. If you need a viewer it is available free at http://www.autodesk.com/products/whip/index/htm . If you prefer I can convert it to .dxf .wmf .eps or .bmp. This suspension has no relationship to any car, it is just a "reasonable facsimile" of an illustration from Chassis Engineering. Someone said that the harder you defend a position the more likely you are to be wrong. Prolly a corollary to Murphy's Law. So, like Bruce's ECM, I'm going to "bench" this thing and build a half-scale model and see what happens as soon as I have the chance. Maybe both Andy and I will learn something. Maybe that lesson will be to suggest Shannen switch to Decaf :-). I'll let you know how it works. Regards, Joe ------------------------------ From: Shannen Durphey Date: Thu, 18 Mar 1999 21:39:54 -0500 Subject: Re: Conversion to EFI : Fuel system First off, I haven't read any of these books, but Bruce gives practical advice, good for following. Mitch wrote: > I am thinking of purchasing the > same engine and transmission combination (pre-93) from a local salvage yard > specializing in Camaros and installing it in a 66 Malibu I have which will > serve as a mule for EFI work. Instead of getting > custom-made fuel tanks, I'd like to implement the dual-pump external fuel > reservoir system described in Knell's TBI/TPI book. > > I am working this out step by step. To discuss this with you folks and > some other buddies, I have put some drawings up at: > > http://www.employees.org/~ozyman/carstuff/efi_fuel.htm > > There are a number of vexing issues. > > 1. Where should the main return line go? Knell's book suggests back to the > remote fuel reservoir, but I was concerned about heat. I was thinking that > it would be best to return the fuel that has been to the intake manifold > back to the large tank. If you return it to the small tank, some of it > goes back to the manifold for further heating. If you return it to the > large tank, there is no such problem. > > Now, my guess is it doesn't hurt to do it this way, but I was wondering > what the logic is for returning back to the remote reservoir. I asked > Knell about this, and he said if you don't return to the reservoir you can > suck air if you run out of fuel from the main tank. But if you run out of > fuel you run out of fuel; returning to the remote reservoir will maybe give > you another minute or so of life. Add the word momentarily in between "you" and "run", suggesting that any forces that pull fuel away from the pickup tube in the main tank cause immediate starvation of the main pump. Returning fuel to the remote tank reduces the overall amount of fuel pumped out of the remote tank and increases the chances that the main pump will recover from starvation before the remote tank empties. > > 2. What is the air pressure in the main fuel tank? Is it positive or > negative? I am concerned because I thought the charcoal canister works > with positive air pressure in the fuel tank, and I don't see how it can be > positive in my diagram. I have been assured from several quarters it is > about 1-2psi positive, but was looking for an exlpanation of this, since > you are always sucking fuel out of the tank. > Well your concern about hot fuel holds the key to that. As fuel heats up, it creates vapors. The gas cap is a check valve that keeps the vapors in the tank. Simce the pump isn't picking them up, they have to go somewhere. In the early '70's it was out the vent tube, then came the charcoal canister. > > 4. Just some general stuff: I am concerned about noise. One idea I had was > to make this an assembly and mount it on rubber mounts, like motor mounts. > I was definitely considering some kind of case or cabinet (steel (like an > old toolbox) or plastic), but I am concerned about the hazard of buildup of > fumes, and also cooling for the pumps. I'd need some way to vent the > thing. I wonder whether it would be overkill to build some cooling/venting > fans into the cabinet. By "this" I assume you mean the remote tank. To prevent bomb situations, your remote tank needs to be full of fuel/vapor and air free. This is what keeps the stock tanks from igniting. But this is not an area for guessing! > > So if you folks have any advice or ideas on this, please let me know. I'll > continue to refine the diagrams as I nail this down. After fooling around > with the stock TBI Malibu, I expect to convert the 327 in my garage to TBI > or port injection the diy_efi way. > Why not find an EFI factory tank that will fit under the Elky? Engineering and design work has been done for you, by professionals. It's not too hard to change fill tubes and tank strap locations. 'Sides, the stock 66 tank doesn't have the charcoal canister connections or return line, AFAIK. And if you have safety inspections where you live, seeing non stock fuel system might make inspectors nervous. Shannen > Cheers, > > Mitch Barrie > Goat Hill, CA ------------------------------ From: Tom Sharpe Date: Thu, 18 Mar 1999 20:51:24 -0600 Subject: Re: Conversion to EFI : Fuel system Mitch wrote: > There are a number of vexing issues. > > 1. Where should the main return line go? Wait for my PWM pump controller and run no return line. > 2. What is the air pressure in the main fuel tank? With a return line it is very positive because of the fuel heating.. > 3. Does it matter whether the pumps are above or below the fuel tank? Pumps don't suck very well.. as long as you are close to the bottol, you will be fine. I mounted an external pump to a bracket fastened to the floor between the tank and the differential. I should haveb welded it to the tank Ha Ha > 4. Just some general stuff: I am concerned about noise. It's noisy but you can't hear it over the motor... (headers and side pipes) Good luck Tom ------------------------------ From: "Ferman C. Lao" Date: Fri, 19 Mar 1999 11:21:42 +0800 Subject: Re: Shift light Thanks Clarence. But the one I read about from this discussion list didn't use 'pills'. It was adjustable over a 5K range which you would specify , i.e. 3500-8500 & so on. I think it was sold my the guy who also made it & not thru stores. I read about around November 98. - -----Original Message----- From: Clarence L.Snyder To: diy_efi@xxx.edu> Date: Friday, March 19, 1999 6:08 AM Subject: Re: Shift light >Autometer makes one - available from Summit for $61.50 with amber light >and requires "pill kit" to select RPM. Kit is 21.69 per range. > ------------------------------ From: "Gary Derian" Date: Thu, 18 Mar 1999 23:01:40 -0500 Subject: Re: Off Panhard Bar Hi Joe The Alfa setup has no bind because the angled arms intersect at the joint. When two arms are angled to form a virtual apex, they intersect only when the body is level. As soon as the body rolls, these two angled arms become skew and no longer have a virtual intersection. Now that I am thinking about it more, if from a side view, the upper and lower arms are parallel, binding will not occur, but now there is no anti-squat. Not from torque, anyway. Any other orientation will cause bind when the body rolls. Reversing the arms so the virtual intersection is in front of the axle does not change the roll center location. The roll center is always in the vertical plane that contains the axle shafts. A line has to be drawn rearward from the virtual intersection, parallel to the lower control arms until it intersects that plane. If both upper and lower control arms form a virtual intersection, a line is drawn through both intersections. Where that line intersects the vertical plane is the roll center. Where did you post that drawing? Gary Derian > > >>There was a general discussion of rear suspension design. My point was >that >>a 4 link, where two of the links are angled to provide lateral location >will >>bind up when the car leans in a corner. One angled link will pull forward, >>the other will push rearward. The amount is small but it is there. With >>rubber bushings, it works OK. This type of 4 link is popular on many US >>cars, notably GM intermediate and full size and Ford Fox chassis Mustangs >>and their siblings. >> > >Wouldn't the upper bars pull/push the same amount if spaced exactly >>>>the same distance apart from the center? I need to draw something to >>>>understand this better. > > >>No. The binding is not from the change in angle between the rod and the >>pivot axis. Its because one link tries to rotate the axle pinion up and >the >>other tries to rotate the axle pinion down. This occurs only when the body >>rolls. > >> >Hello Gary, > >I was going to send this off list, but in view of the other interest I >thought I'd share. > >Earlier in this thread Greg wrote: >"Or go scrounging in a boneyard that has some old Alfas. They used an upper >triangle, with two pivot points on the chassis, and a BALL joint attached >just to the left side of the pumpkin, plus two lower trailing arms. >Particularly if you replaced the chassis pivots of the triangle (rubber >stock) with bronze on steel, also if you replaced the lower rod ends with >real rod ends, they were as NICE a live rear axle setup as you could want." > >I believe that this worked, and worked well. The ball joint located the roll >center. As the body rolled in a turn, the worst action I can see is that the >axle rotated slightly. Most certainly there was not binding, even with rod >ends and bronze bushes, in spite of the off center location. Some might even >suggest that the roll center would be better placed to the right, since this >is the side which unloads under acceleration. I think this demonstrates how >much a design can deviate from a theoretical ideal, or how much you >sacrifice an ideal in one area chasing the overall performance of a system. > >When I suggested two angled arms, I saw a virtual triangle with the roll >center located where lines projected from the arms intersected the >centerline of the axle. In this case we have two rod ends in shear rather >than a single ball joint with bending stress. As long as I picture this >virtual triangle, I can so no reason for bind. The virtual triangle acts the >same as the real one. > >Also, I don't see any reason not to turn this virtual triangle around so the >base is connected to the axle. The virtual apex still determines the roll >center, the body will roll about this point, and the axle will still rotate >slightly, but still no bind. Now the roll center has a more constant >relationship to the center of gravity, and since this relationship >determines the amount of body roll, perhaps the car will behave more >consistently. > >As I have said before, ASCII is not an easy medium. It's hard to describe a >concept in a concise manner and show a rapier like wit at the same time. :-) > >Maybe we are not seeing the same picture. I know now that I wasn't when I >visualized >your description of the torque arm setup from the Vega. To that end I have >posted an AutoCad Whip file which contains a drawing of a Satchell Link >suspension to incomming, Satchell Link.dwf. If you need a viewer it is >available free at >http://www.autodesk.com/products/whip/index/htm . If you prefer I can >convert it to .dxf .wmf .eps or .bmp. >This suspension has no >relationship to any car, it is just a "reasonable facsimile" of an >illustration from Chassis Engineering. > >Someone said that the harder you defend a position the more likely you are >to be wrong. Prolly a corollary to Murphy's Law. So, like Bruce's ECM, I'm >going to "bench" this thing and build a half-scale model and see what >happens as soon as I have the chance. Maybe both Andy and I will learn >something. Maybe that lesson will be to suggest Shannen switch to Decaf >:-). > >I'll let you know how it works. > >Regards, > >Joe > > > > > > > > > > > > > > ------------------------------ End of DIY_EFI Digest V4 #179 ***************************** 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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