DIY_EFI Digest Saturday, 12 October 1996 Volume 01 : Number 311 In this issue: re: Re: Re[2]: Using pc parts RE: Thermocouple in EGR port Air Flow Meter RE: IGNITION PROJECT Re: ignition reference See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: SRavet@xxx.com Date: Fri, 11 Oct 96 17:17:47 CDT Subject: re: Re: Re[2]: Using pc parts "Dan J. Declerck" Wrote: | | > | > | > So here's a thing. I remember one of those irritating Infiniti commericals | > about a year ago when the the Infiniti poster boy was talking about an | > in-car lan. I know nothing about it. Does anyone? Is there something we | > can salvage from it? What was on it? Are the transcievers cheap? | > | > Thanks, | > Dan | | | There's a number of people whom make these car Lan transceivers. | The CAN bus is primarily used by BMW, I think they get their parts from Seimens | but I am not sure. | | I (squared)C is another bus type. I am not sure who uses this. I2C is used (for example) in computers for cummunication between the power supply and the motherboard. | | The point is: there is NO standard for automotive communication busses. This isn't true. OBD-II has mandated a standard for auto busses. It comes in a 2 wire and a 3 wire version. The spec covers both the electrical specification, the format of data packets, and what basic information must be made available. Manufacturers are free to add other info and not disclose it, but the OBD-II compliant part is public information. Steve Ravet sravet@xxx.com Baby you're a genius when it comes to cooking up some chili sauce... ------------------------------ From: jac@xxx.us Date: Fri, 11 Oct 96 17:37:00 PDT Subject: RE: Thermocouple in EGR port Depending on the response time you can accept of course, the most available and handiest thermocouples are the ones intended for recip engined aircraft. They are scheathed with stainless and properly insulated. In the us you can get them from sport aviation suppliers for $30 or so at the very worst price. They come with a fiber glass wrap on the leads and will survive in the engine environment. - ------------------------------------- john carroll jac@xxx.us - ---------------Original Message--------------- Hi all, After having taken the head off an engine i've got lying around, i've noticed that there is a threaded hole under the exhaust port for what my brother tells me is for EGR. This would be a great place to put a thermocouple for egt sensing. What i would like to know is is there some way of putting a thermocouple in this port so that i can measure the exhaust temperature, and if so, how could i go about fitting this in the port. I've thought about drilling the centre of a bolt out so that i could run the wire through this, and the end poking into the exhaust. The issue of insulation would come into this. The only way that i could think of insulation between the wires at these temps is by ceramic fillers of some sort. Do such exist? Is there some way of fastening a thermocouple into a threaded hole that someone has come up with already? There being 4 ports for the EGR, it could be possible to measure the temp of each cyliner individually, and RIGHT AT the port. Any comments would be most appreciated. Thanks. Bruno. (b.marzano@xxx.au) Smile. It makes people wonder what you are thinking about. - ----------End of Original Message---------- ------------------------------ From: William Boulton Date: Sat, 12 Oct 1996 10:50:03 +1000 (EST) Subject: Air Flow Meter Andrew, I have serious doubts about this bigger flow meter stuff. Before you embark on fitting another flow meter, I think it would be a good idea to determine if the flow meter is offering any significant restriction. Don't just assume that it is. Do a pressure drop test accross it. It does not make sense that the manufacturer would fit one too small. The vane would bottom out before full flow was reached. The flow meter is the systems only load sense so the ecu could not determine fuel requirements beyond that point. Result? High speed lean out and a big warranty claim. I don't think they are that stupid! As for the throttle body being too small and the inlet runners as well, I think you overlook a significant number of facts. Inlet tract size (length & diameter) is based on gas velocity requirements, cylinder volume and sound wave propergation. It was demonstrated 25 years ago that high power output did not equate to the biggest possible valves, inlet passages and throttle size. In my not so humble opinion, I think you are embarking on the degradation of your low speed performance and drivability. There is no point in having an inlet tract that will pass x+y cfm when the engine will barely consume x cfm at full noise. Get my point? Bill Boulton ------------------------------ From: marchildon@xxx.net (Alain Marchildon) Date: Sat, 12 Oct 1996 01:02:09 GMT Subject: RE: IGNITION PROJECT John Wrote i sniped a lot >I will post the whole project if people want to work on it and >improve it. I am not the least bit interested in distributing a >bunch of code and drawings so that folks can argue about processors >or programming technique without contributing significantly to the >project. I am interested and the DIY_EFI is not just for EFI but for also for electronic ignition control. > This may not be the proper forum for this project and I >do not have the time to manage another one. If I figure out how to >use it I guess I have an FTP site available. If you are interested >in extending this project, post your thoughts or e-mail direct. Just take a look at http://www.cpsc.ucalgary.ca:80/~fridman/diy_efi/ This is the DIY_EFI home page and there is a projects section, and this would qualify as a project for the DIY_EFI list. // Marchildon@xxx.net // // Alain Marchildon // // 1984 Mazda RX-7 GSL-SE Soon with Vortech supercharger "My toy // // 1989 Audi 90 "Family car" // ------------------------------ From: Sandy Date: Fri, 11 Oct 1996 22:29:13 -0700 Subject: Re: ignition reference [Snip] >Two quick points here, firstly I'm pretty certain that a VRS sensor >won't trigger with a plastic wheel, They won't, but for those that may want to try making a simple LED Beam Breaker, the can use that method with a plastic wheel. >Secondly, you may find that the type of wheel that will interface >sucessfully with any given ECU in terms of teeth thickness, teeth >size, inter-teeth gap and mark-space ratio, is a function of the >VRS input circuitry in that ECU. For example, if the teeth are too >close together you may fail to detect a good clear zero crossing at >high RPM. > I thought they were trying to make the whole thing from scratch, not to interface to an existing ignition system, if that were the case, they could just use the stock interrupter or what ever the trigger is. >In essence, I'd be very surprised if it didn't matter what shape and >size the wheel is. > Much stranger things have happened, some thing work with a wide lattitued for errors, but I would expecte that anything I am working on will not have that kinda' luck ;-) Sandy ------------------------------ End of DIY_EFI Digest V1 #311 ***************************** 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".