DIY_EFI Digest Monday, 11 March 1996 Volume 01 : Number 073 In this issue: Re: Encoder Re: volumetric efficiency equations UEGO sensor RE: Encoder Re: Toyota ECU mods Re: volumetric efficiency equations EGT for mixture setting? Al u-bends EFI without a lookup table See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: Bill Lewis Date: Sun, 10 Mar 1996 08:10:34 -0500 Subject: Re: Encoder >> That's less than 28 hours at 6000 rpm. Are you sure there isn't >> another 1000 in there? > When was the last time you saw a Briggs + Stratton doing 6000 RPM? Modified Briggs and Stratton engines used for go-kart racing spin well over 5000. Bill ------------------------------ From: Jim Zurlo Date: Sun, 10 Mar 1996 08:51:38 -0600 (CST) Subject: Re: volumetric efficiency equations As mentioned by the guy from Ford, if you really want to accurately calculate volumetric efficiency then you must use a sophisticated program such as Ford's MANDY (can you send me a copy of that? :-)). However the book by Taylor & Taylor from MIT Press does have some equations that indicate how various changes effect volumetric efficiency. An example is the equation that shows how volumetric efficiency is affected by the ratio of Intake to Exhaust manifold pressure. For some applications that level of sophistication is sufficient. Jim Zurlo zurlo@xxx.com ------------------------------ From: JC_ZHOLIDAY@xxx.GOV Date: Sun, 10 Mar 1996 10:19:45 -0400 (EDT) Subject: UEGO sensor I'm currently doing some research for a port fuel injection system that I want to build. I'm wanting it to be able to measure the true a/f ratio or at least as close as possible to it. What I'm needing is some information on interfacing with UEGO sensors. Also, I've seen a few posting and articles refering to SAE papers or journals, how can I get a hold of these? Ezekiel Holliday JC_ZHOLIDAY@xxx.GOV ------------------------------ From: Grant Beattie Date: Sun, 10 Mar 1996 09:27:29 -0700 (MST) Subject: RE: Encoder On Sat, 9 Mar 1996, dn wrote: > When was the last time you saw a Briggs + Stratton doing 6000 RPM? Last race! My B&S does over 6000 every lap (a go-kart race). GB ------------------------------ From: "Gregory Chan" Date: Sun, 10 Mar 1996 12:19:03 +0000 Subject: Re: Toyota ECU mods Hi all, I'm new on this list and am in search of any information which may give me an insight to how I can modify the ECU on an 85 Corolla GTS. I have already performed most of the external mods such as airflow meter, EGR valve, temp sensor pot and am currently looking into getting larger injectors. The stock Toyota ECU does not have numbers which I can understand (i.e. by checking in an ECG replacement guide) or a removable EPROM. Does anyone know of any mods to this ECU ( I have a spare one) or can put me on to a source of information? Thanks in advance. gchan@xxx.ca ------------------------------ From: Land Shark Date: Sun, 10 Mar 1996 10:08:06 -0700 Subject: Re: volumetric efficiency equations At 08:51 3/10/96 -0600, you wrote: >As mentioned by the guy from Ford, if you really want to accurately calculate >volumetric efficiency then you must use a sophisticated program such as Ford's >MANDY (can you send me a copy of that? :-)). Uhh .. what he said ;) >However the book by Taylor & >Taylor from MIT Press does have some equations that indicate how various >changes effect volumetric efficiency. An example is the equation that shows >how volumetric efficiency is affected by the ratio of Intake to Exhaust >manifold pressure. For some applications that level of sophistication is >sufficient. Could you give me a cite for said book, and also whoudl you be kind enough to summarize (or just dump) that formula ... I'm VERY curious as to the effect of Exhaust backpressure on Ve ... Jim (about to supercharge an M3) Conforti ------------------------------ From: jsturs@xxx.nl (Jim Sturcbecher) Date: Sun, 10 Mar 1996 23:51:53 -0100 Subject: EGT for mixture setting? Could somebody please explain the relationship between EGT and mixture in a practical sense for tuning purposes, i.e. how would you actually go about setting fuel curves based on EGT readings? Later, Jim Sturcbecher jsturs@xxx.nl ------------------------------ From: dhe1@xxx.edu (Dan Elsberg) Date: Sun, 10 Mar 1996 19:38:00 -0700 Subject: Al u-bends We got tired of the high prices and low availability of Aluminum u-bends so we made a mandril bender. It was a _lot_ of work. (about a week of machining and then another couple of days playing around with the technique.) Anyway if anyone needs 1-3/8"x0.058 we may be able to work something out that would be a lot cheaper than the estimates we got from various other sources (one wanted $275 to bend 6 semi-circles (180 degrees) including the labor and material). E-mail me directly if you want to talk about it. If anyone wants a description of the tool we made e-mail me about that too. - --dan - -- Dan Elsberg (607) 272-1574 Cornell University, Engineering Physics dhe1@xxx.edu ------------------------------ From: Bruno! Date: Mon, 11 Mar 1996 13:54:49 +1100 (EDT) Subject: EFI without a lookup table Hi everyone, Is it possible to have an efi computer control the engine entirely in closed loop? I'd like to design a ecu which does not rely on having to be dyno-tuned, or other ways where the engine has to run at different loads, speeds, etc. The rationale behind this is I want to be able to design the computer, plug it in, and control the engine from day one. I understand that there are more things to consider, what they are exactly are slowly coming to me. For a start, I was thinking of using a MAP, TPS, and a crank angle sensor (for RPM) and intake air temperature for airflow metering, and an O2 sensor for mixture. When using a hall effect sensor, what is the material that the metal vane that passes through the gap made of? Iron or aluminium? Any thoughts or suggestions would be most welcome. Thanks. Bruno. ( u933234@xxx.au ) "If you've gotta go, go with a smile" ------------------------------ End of DIY_EFI Digest V1 #73 **************************** 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".