DIY_EFI Digest Thursday, 15 February 1996 Volume 01 : Number 043 In this issue: Re: Sequential Setup? <911> Bosch Motronic Re: Sequential Setup? Re: <911> Bosch Motronic Re: Sequential Setup? GM Model 700 Throttle Body Re: MAP Questions... Re: MAP Questions... Re: MAP Questions... Re: <911> Bosch Motronic Re: GM Model 700 Throttle Body Re: MAP Questions... See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: Tommy.Palm@xxx.se Date: Wed, 14 Feb 1996 10:22:29 -0500 Subject: Re: Sequential Setup? >I carried out some (well alot of) research on this subject from a combu= stion >point of view. I saw a reduction in harshness (uneven combustion) and >INCREASE in Power (Torque) when you FINISHED or JUST FINISH injecting t= he >fuel just before the inlet valve started to open. = > >R.S.Sian > = Since this seems to be a ongoing topic I might help someone with some information from SAE transactions were Toyota carried out a very serious= tests on sequential timing and affects on combustion. It was done for their le= anburn engine to use mixtures leaner than 22:1 and still comply to harshness an= d mostly polluton NOx. Lots of interesting grafs that mostly agrees with M= r Sians research. I also have an astonishing report on the effect of injector ai= ming. Interested? = Excuse my swedish-english (one bearly dear to write in this group anymor= e)! Tommy Palm tommy.palm@xxx.se ------------------------------ From: BANESI@xxx.com (Brad Anesi) Date: Wed, 14 Feb 1996 07:57:36 -0800 Subject: <911> Bosch Motronic If you don't know/care about a Motronic-equipped '86 911, feel free to hit the delete key now.... There was a recent posting on the Alfa Digest about helping water-cooled, Motronic-equipped Alfas start and run easier when cold by measuring the resistance of the coolant temperature sensor and adding some calculated resistance to this circuit. My Alfa runs great when cold, but my 911 tends to stumble a bit when cold. I'd like to try to apply the same process to my 911, but obviously we have a different animal here. My questions: 1) Does the engine temperature input (at startup) for the 911's Motronic use the oil temperature, head temperature, both? 2) Any idea if the process described above (I can provide further details), would work for a 911? Thanks, Brad '86 911 Coupe '91 Alfa 164 ------------------------------ From: John.Beggs@xxx. Beggs) Date: Wed, 14 Feb 96 11:57:05 PST Subject: Re: Sequential Setup? Yes I am interested in reading the report. Please post. PS, Your English is AOK. >From someone who speaks the Queen's English. >Lots of interesting grafs that mostly agrees with Mr Sians >research. I also have an astonishing report on the effect of injector ai= >ming. >Interested? = > -------------------------------------- | John W. Beggs, | | BC Hydro, | | 6911 Southpoint Drive, | | Burnaby, B.C., V3N 4X8, Canada. | | (604)528-2776; FAX (604) 528-1883| -------------------------------------- - -------------------------------------------------------------------- ------------------------------ From: arthurok@xxx.com (ARTHUR OKUN ) Date: Wed, 14 Feb 1996 14:50:25 -0800 Subject: Re: <911> Bosch Motronic i thought about doing that on gm system the only problem is that sensors output is non linear and putting in a series resistor would seriously distort the high temp calibration . how about a switch or relay to put in a fixed resistor of your choice for cold start ? the way i "solved " my problem is by replacing the temp sensor with a new one that had a better "curve" the chilton said this occasionaly is a problem with "marginal" engines. when i put the old sensor "water" in the freezer at 5*f i found it to be reading about 10* high according to a gm resistance table they say the resistances are approxamate but the new one read exactly the table values . believe me it made a noticible improvement. these measurements were made with adigital dmm that im sure is accurate to better then 1% on resistance. in conclution check and or replace the the temp sensors the strange part is that i replaced the same sensor with a new one 6 months before because of error codes but did not check it before installing it "why bother its new?"" ------------------------------ From: fcmefi@xxx.net (Fred Miranda) Date: Wed, 14 Feb 1996 19:12:18 GMT Subject: Re: Sequential Setup? >Yes I am interested in reading the report. Please post. me too, very much so. >PS, Your English is AOK. ditto, in fact I have no problem with anyones english or spelling on this list. how could I? Fred ------------------------------ From: orin@xxx. Harding) Date: Wed, 14 Feb 1996 22:04:30 -0500 Subject: GM Model 700 Throttle Body Does anyone have any information on the injector used in the GM 700 throttle body? I'm trying to use one on a 1.8L MGB engine and the one I have (off a 2.5L from a Grand Am) isn't flowing enough fuel at WOT. I need one that will flow about 55#/hr. Any suggestions?...Thanks.. Orin Harding - Greensboro, NC ('74 MGB-GT - '79 MGB Roadster with Electromotive TEC II) ------------------------------ From: "Clinton L. Corbin" Date: Wed, 14 Feb 96 20:04:17 PST Subject: Re: MAP Questions... >how about a servo controlled throttle plate if done propperly it >might alliviate alot of efi problems caused by manualy controled >throttles : just think no more lead foots causing the manafold >pressure to go down to next to nothing. Quick question: Do you REALLY want a computer controlling your throttle position? Face it, a throttle cable (or linkage) and return spring is a pretty reliable, and proven, system. It might make things a bit interesting if the computer decided that the throttle plate was at idle position when it really was at WOT. And besides, what is wrong with a bit of lead footing? Next thing you know, you will be suggesting a built-in traction control system! ;) Actually, I like the idea of being able to use a traction control. It would come in real handy on ice. I just want to be able to choose WHEN it does its traction control thing. Later. Clint ccorbin@xxx.com ------------------------------ From: Steve Baldwin Date: Thu, 15 Feb 1996 17:50:15 +1300 (NZDT) Subject: Re: MAP Questions... > Quick question: Do you REALLY want a computer controlling your throttle > position? Face it, a throttle cable (or linkage) and return spring is > a pretty reliable, and proven, system. It might make things a bit interesting > if the computer decided that the throttle plate was at idle position when it > really was at WOT. And besides, what is wrong with a bit of lead footing? > Next thing you know, you will be suggesting a built-in traction control > system! ;) Actually, I like the idea of being able to use a traction > control. It would come in real handy on ice. I just want to be able to > choose WHEN it does its traction control thing. Later. > Do mean like a cruise control that won't let go or a power steering system going open loop. Even (very) assisted brakes spell death if they pack up just as the car in front throws out all the picks. I wouldn't be too keen on a wire-wrapped, "my first micro project" based system but with due care and attention it's not really any different from other technology in a car. Steve. ------------------------------ From: "Clinton L. Corbin" Date: Wed, 14 Feb 96 21:23:20 PST Subject: Re: MAP Questions... >> Quick question: Do you REALLY want a computer controlling your throttle >> position? Face it, a throttle cable (or linkage) and return spring is >> a pretty reliable, and proven, system. It might make things a bit interesting >> if the computer decided that the throttle plate was at idle position when it >> really was at WOT. And besides, what is wrong with a bit of lead footing? >> Next thing you know, you will be suggesting a built-in traction control >> system! ;) Actually, I like the idea of being able to use a traction >> control. It would come in real handy on ice. I just want to be able to >> choose WHEN it does its traction control thing. Later. > >Do mean like a cruise control that won't let go or a power steering >system going open loop. Even (very) assisted brakes spell death if they >pack up just as the car in front throws out all the picks. >I wouldn't be too keen on a wire-wrapped, "my first micro project" based >system but with due care and attention it's not really any different >from other technology in a car. >Steve. Good point, Steve! Clint ------------------------------ From: Land Shark Date: Wed, 14 Feb 1996 22:30:19 -0700 Subject: Re: <911> Bosch Motronic At 07:57 AM 2/14/96 -0800, you wrote: >If you don't know/care about a Motronic-equipped '86 911, feel free to hit >the delete key now.... How about, that I have the SOURCE code to the 911 :) >1) Does the engine temperature input (at startup) for the 911's Motronic >use the oil temperature, head temperature, both? Cylinder head temp`... >2) Any idea if the process described above (I can provide further >details), would work for a 911? We can always update your DME to the 1988 programming ... Jim PS: I presume the novell.com address is in Provo, I am in Salt Lake!! > >Thanks, > >Brad >'86 911 Coupe >'91 Alfa 164 > > > > - -------------------------------------- Jim Conforti Great Salt Lake Bimmers Chapter, BMW Car Club of America 95 M3 LNDSHRK 94 325i Mac - -------------------------------------- ------------------------------ From: arthurok@xxx.com (ARTHUR OKUN ) Date: Wed, 14 Feb 1996 23:48:28 -0800 Subject: Re: GM Model 700 Throttle Body whats your inlet fuel pressure at wot ? also check your pressure reg or try plugging the t body fuel return line to get more pressure; you should have at least 25 lbs with the engine not running return line connected a good new intank fuel pump will generate close to 40 psi . ------------------------------ From: arthurok@xxx.com (ARTHUR OKUN ) Date: Thu, 15 Feb 1996 00:09:32 -0800 Subject: Re: MAP Questions... i think most efi systems would work horribly without a tps ; so you can see that a throttle servo is the next logical step ; a iac is a limited version of this " like vernier servo" ------------------------------ End of DIY_EFI Digest V1 #43 **************************** 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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