DIY_EFI Digest Saturday, 23 August 1997 Volume 02 : Number 285 In this issue: Re: TPI Questions Re: BOSCH stuff Re: BOSCH stuff See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: "Greg Abarr" Date: Fri, 22 Aug 1997 19:15:16 -0500 Subject: Re: TPI Questions - ---------- From: Bill Bradley To: diy_efi@xxx.edu Subject: Re: TPI Questions Date: Friday, August 22, 1997 3:01 PM > > Bear in mind that water or water/methanol injection will exert a powerful > > cooling effect on the mixture rather than merely diluting the mixture > > with hot, inert, gasses. > > Bill in Boulder "Engineering as an Art Form" > > Hey, that's my idea. :-) Unfortunately you have to alter the air intake > to compensate for the fuel displacement if water is injected, and > methanol has a lower available btu, not to mention air/fuel ratio > compared to gas. Nope. The water or methanol replaces AIR, not fuel. The mixture goes rich running water or water-alcohol injection. Unless you're still running closed loop with the Oxygen sensor which will try to bring it back to stoic. > it to drive a cooling unit, (like a propane fridge principle), to cool > the air, and then jam as much air directly into the injector stream as > possible. The rest of the air charge requirement is sucked up normally > on the intake. I've considered the idea of a heat powered heat pump as a killer intercooler design. The drawbacks are that there are two common designs, one uses Hydrogen gas and Ammonia (not that namby-pamby 2.5% stuff that you use to clean things, REAL concentrated toxic, corrosive ammonia). The other system uses water and lithium bromide salt, much nicer, but has the annoying habit of freezing when it gets cold... Both systems also dump more heat OUT than you put in, so you have to have a decent cooling system for it as well. Bill diy_efi unscribe greg@xxx.com Sir: I am going away for 2 to 3 months and i need to stop all my e\mail groups Thank you Greg Abarr ------------------------------ From: Michael McBroom Date: Fri, 22 Aug 1997 17:35:58 -0700 Subject: Re: BOSCH stuff Steve Meade wrote: > > I have a bit of Bosch FI confusion. Porsche refers to the engine > management system in my 944 as being Digital Motor Electronics. I thought > that this pretty much translated into Motronic for all practical purposes. > Then, I bought a Haynes manual for my car which says I have an L-Jetronic > fuel injection system controlled by Digital Engine Electronics. To confuse > matters even more, a Porsche site (non factory) proclaims me as having a > JE-Jetronic system. This morning, I took apart part of the floor and got to > the ECU to see exactly what it said. It is the familar "tab-cover" box with > "Motronic" embossed in the case. I looked at the number on the box and it > started with "261" the same as on my '87 BMW 325is with Motronic 1.1. It appears that you have uncovered the truth. According to Charles Probst in his book _Bosch Fuel Injection & Engine Management (Robert Bentley, 1991), all 944s have Bosch Motronic systems. He makes no mention of JE-Jetronic, although he mentions a few variants of K-Jetronic, one of which is KE-Jetronic. Citing from Probst again, there are three basic Motronic systems (up to 1991, that is): Motronic, LH-Motronic, and KE-Motronic. Yours should have the plain Motronic system (and yes, Probst shows your 325 as using the same one), which is characterized as having such basic features as an air-flow meter, pulsed injection, idle stabilization, and ignition timing control. Incidentally, I can recommend Probst's book. I bought it to learn more about Bosch efi systems in general and LH-Jet in particular, and it has helped in that regard. I wish he would have gone into considerably more detail in several areas, but it has served as a very worthwhile introduction. - -- Best, Michael McBroom '87 745T 123k w/APC Visit the Volvo Performance Site: '88 765T 156k http://mcbrooms.com/volvo _________________________________________________________________________ Graduate Student, Linguistics Author of Research Interest: Biological Origins =McBroom's Camera Bluebook= of Language http://mcbrooms.com California State University, Fullerton _________________________________________________________________________ ------------------------------ From: Land Shark Date: Sat, 23 Aug 1997 00:20:03 -0600 Subject: Re: BOSCH stuff At 12:57 PM 8/22/97 -0700, you wrote: > > I have a bit of Bosch FI confusion. Porsche refers to the engine >management system in my 944 as being Digital Motor Electronics. Motronic all 944's in the US are Motronic DME If you tell me your 0 261 number, I can tell you what version any (maybe) the processor type/EPROM type Jim C ------------------------------ End of DIY_EFI Digest V2 #285 ***************************** 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".