DIY_EFI Digest Wednesday, 18 December 1996 Volume 01 : Number 387 In this issue: RE: sensorless electric motor position detection RE: Check out the new diy_efi / efi332 web site! Re: oil pumps (not efi) Re: sensorless electric motor position detection Re: more fuel pressure Re: Fuel pump questions Re: more fuel pressure RE: sensorless electric motor position detection new reader: L-jet problems - help wanted. RE: Check out the new diy_efi / efi332 web site! Re: more fuel pressure Re: Fwd: eddy current brake Re: oil press "gauge" Re: Check out the new diy_efi / efi332 web site! Re: Fwd: eddy current brake cylinder pressure measurement on toyotas? Re: oil press "gauge" Re: cylinder pressure measurement on toyotas? Re: more fuel pressure Re: Fwd: eddy current brake RE: Check out the new diy_efi / efi332 web site! Re: oil pumps (not efi) Re: oil pumps (not efi) Re: more fuel pressure Re: oil press "gauge" See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: "Bob R. McElroy" Date: Tue, 17 Dec 1996 06:04:31 -0600 Subject: RE: sensorless electric motor position detection It was a wheel that you could rotate and a readout that showed position using the signature that the magnet poles made as they spun. I proceeded = to rotate the wheel 180 degrees and behold! a reading that was 180=20 degrees in error! i really didnt expect to fool it, i also could trick=20 its position calculation by quickly passing a mark, then returning it to = that mark. Novel idea, needed more time to complete but looks possible=20 if you can overcome the detection of which magnet winding you were=20 looking at. aparrently its cheating if you manufacture a flaw into a=20 motor winding on purpose.=20 I thought you thinkers would be interested in this. - ------------------ Sounds cool. Who developed it, and when do they expect to have it on = the market? - ------------------ anyway, can someone tell me how ABS detects wheel position/movement? - ------------------ ABS doesn't care what the actual position of the wheel is. ABS only = cares how fast the wheel is turning, as far as I know. The Hall effect = sensor cannot directly measure the acceleration of the wheel, but = compares the currently measured RPM with the previously measured wheel = RPM and calculates the instantaneous wheel acceleration (deceleration.) = A preprogrammed maximum deceleration is then compared to the = instantaneous wheel acceleration. If the computer calculates a larger = deceleration value for a particular wheel, the computer then knows that = the wheel in question is skidding. I don't know if the deceleration = threshold value must be exceeded by a certain amount or for a certain = time length before the ABS computer takes control. Also, there must = exist some hysterisis allowances, since you would want the ABS to take = control of the braking at a different point than you want it to return = control to the driver. The flaw, IMHO, is that an average deceleration = value is programmed at the factory, and doesn't compensate for actual = vehicle weight or the minor variations from vehicle to vehicle. I have = never done a thorough investigation of ABS, and what I know was learned = through reading articles in Motor Trend and my conclusions and = assumptions from that information, so I am by no means any type of = authority on ABS. Any know if my assumptions are even somewhat valid? ------------------------------ From: cloud@xxx.edu (tom cloud) Date: Tue, 17 Dec 1996 07:39:58 -0600 Subject: RE: Check out the new diy_efi / efi332 web site! P-L-E-A-S-E turn off the text encoding !! > > >---------- >From: Johnny >Sent: Monday, December 16, 1996 2:14 PM >To: diy_efi@xxx.edu >Subject: Re: Check out the new diy_efi / efi332 web site! > >> From: Peter Shoebridge > >> Looks pretty good, perhaps you should have a go at the diy_efi and efi332 > >> web pages.... > >Peter, those ARE the diy_efi and efi332 web pages!!! Am I missing >something here? > >I meant these pages: > http://efi332.eng.ohio-state.edu/mirror/ >and > http://www.cpsc.ucalgary.ca/~fridman/diy_efi/ > >> I was away this weekend, so I haven't had a chance to test out the >> gnu-win32 b17 cross-compile tools. Should get to that tonight (yeah >> right!!!). > >Sounds great. Keep us posted on how it goes. Although, I have to admit, the >more I play with Linux, the more I like it. ;-) > >-j- > >begin 600 WINMAIL.DAT >M>)\^(@`6`0:0" `$```````!``$``0>0!@`(````Y 0```````#H``$(@ <` >M& ```$E032Y-:6-R;W-O9G0@xxx.;W1E`#$(`0V ! `"`````@`"``$$ >MD 8`9 $```$````,`````P``, (````+``\.``````(!_P\!````8P`````` >M``"!*Q^DOJ,0&9UN`-T!#U0"`````&1I>5]E9FE 8V]U;&]M8BYE;FM;RUS=&%T92YE9'4`4TU44 !D:7E?969I0&-O=6QO;6(N96YG+F]H:6\MM=&4N961U```>``(P`0````4```!33510`````!X``S !````(P```&1I>5]E >M9FE 8V]U;&]M8BYE;FM```>``$P`0```"4````G9&EY7V5F:4!C;W5L;VUB+F5N9RYO:&EO+7-T871E >M+F5D=2<``````@$+, $````H````4TU44#I$25E?149)0$-/54Q/34(N14Y' >M+D](24\M4U1!5$4N1415``,``#D`````"P! .@$````"`?8/`0````0````` >M```"VDT!!( !`#$```!213H@0VAE8VL@;W5T('1H92!N97<@9&EY7V5F:2 O >M(&5F:3,S,B!W96(@xxx. `!`%$! >M`2" `P`.````S <,`! `#P`:``$``0`:`0$)@xxx.4$V-C U >M-T0P,3%",T4U,#!!03 P,S@xxx.0!@`D!0``% ````L`(P`````` >M`P`F```````+`"D```````,`+@```````P`V``````! `#D`,,G8/J#KNP$> >M`' ``0```#$```!213H@0VAE8VL@;W5T('1H92!N97<@9&EY7V5F:2 O(&5F >M:3,S,B!W96(@MY0"J`#A;A0``'@`># $````%````4TU44 `````>`!\,`0```!,```!P971E >M``@0`0```&4````M >M+2TM+2TM+2TM1E)/33I*3TA.3EE314Y4.DU/3D1!62Q$14-%34)%4C$V+#$Y >M.38R.C$T4$U43SI$25E%1DE 0T]53$]-0D5.1T](24\M4U1!5$5%1%5354)* >M14-4.E)%.D-(``````(!"1 !````?P,``'L#``!H!@``3%I&=0??J83_``H! >M#P(5`J0#Y 7K`H,`4!,#5 (`8V@xxx.XR!@`&PP*#,@/&!Q,"@Q(S$P]F >M- ]Z:&5LT0,@1&QG`H!]"H (S\4)V3L7GS(U-0* "H&##;$+8&YG,3 S%"#7 >M"PH2\@xxx.# "T6DM>#$T- WP#- >8PM9,;8V"J #8'0% >MD 5 +2"'KPJ''SL,," &1@xxx.`R &#((@2F]H;FY^>2$O(CT&8 (P(V\D >M>TUA`B!D87DL%F %D&4;!M $D" ?T"H@,3DY$#8@,CH>8"!033,EKR(]5&\G >M[R1[9&FD>5\-P&E !:!U%S E!M N"?!G+B50:6^<+7,!D" P,,!D=2O?<2:^ >M=6)J($$M_R1[4HIE-&!#%B!C:R (8&4%0'06("!N!]$OU2"<+R P$1K@$B!W >M924@xxx., %$&1G-T \ >MHG \TD!AMX'(1P'IP!"!Y"& XX#TP,'!DZB 1P'8W0&% T4*P-P3_-Z8`<$)0.$0_'CBR >M"K ]H+\^L$8Q.4P\PRH@xxx.$E%XR%*8((@$W!M($D@;00! >M]0N 9PJ%MA24": ) <#HO+SA$*S#/,= O2P!R`V!R+^].-40!46]2<'=6<#[ 09!08RYU >M8P= 9PK >7$^P&$O?@xxx.L\[UTK@=SY /T*P7!! P$PA >M!" XL&5KGPGP01%+X$K10G)N)P5 [Q' 0E!"P!&Q;BI@-Q!"\ \@,#%@-M<_ >MAV=N=2W%`_!N.(%B,3=>H -@]000+3[1< ,07P(&\#ZP_ST20C(]H#MP&-R`P"B9U(@("AY4%!H/WC7!1!D44IA*49M4PA@*> O!" )P3& 8L!+">!P >M('YU0%%'X" P0E "($)@;U\'X#D`0-$^H1-P;$?!=;]D4"H@7;1?$EY@2P!T >M1Z+^94XU!& 7H$K1"U% P /PYS<@0 `+@'5X:V-L%AW AUT@:3%BP" [+2E8 >MW/PM:B$86=\;U2 &3C46P0(`\= >MH.N[`4 `"# `">\=H.N[`1X`/0`!````!0```%)%.B ``````P`--/TW``": >!=.N[ >` >end > > > Tom Cloud ------------------------------ From: cloud@xxx.edu (tom cloud) Date: Tue, 17 Dec 1996 07:46:30 -0600 Subject: Re: oil pumps (not efi) > >-> WRONG. Why the heck would it be called a high volume pump if it >-> didn't pump more volume per revolution?!?!? If you carefully compare [ snip ] > For ordinary Ford and Chevy applications there is an internal bypass in >the actual pump casting itself. A spring loaded plunger in the bypass [ snip ] Forgive me for bringing this subject up on the efi list. Clearly, it has more than run its course. Thanks to all who tried to enlighten me. Tom Cloud ------------------------------ From: kleenair@xxx.com Date: Tue, 17 Dec 1996 08:19:32 -0800 Subject: Re: sensorless electric motor position detection Dave Zug wrote: > > anyway, can someone tell me how ABS detects wheel position/movement? > (keep this one for the FAQ!) > > and, is ABS considered EFI related? (be nice) Hi Dave, Most ABS systems use a tooth wheel at the hub. I'm pretty sure most system detect a wheel slip condition by calculating the deceleration rate of the wheel. Although its not EFI, many of the same processes apply to ABS Mazda ------------------------------ From: kleenair@xxx.com Date: Tue, 17 Dec 1996 08:24:13 -0800 Subject: Re: more fuel pressure Dave Zug wrote: > > I was given a tip on my car's website, that if i "crush" the pneumatic > pressure regulator on my 3.1L PFI-T pont. engine, i'll get more fuel for > a given vacuum. this is because you'd be loading the spring inside the > regulator. I absolutely am NOT going to do this, but does anyone have > another way to affect that regulator without buying boosters etc? its > ONE thing that my ECM CANT alter, that i'd like to. is it > disassemblable? > > ps I have only 40 psi at idle and 60 psi at WOT. > > later~ > dave @:-)-[--< I don't know if its disassemblable, but if you run a higher pressure across the operating range, the adaptive learn will simply correct for the overfueling. The only way around it is to disconnect the O2 sensor and raise the pressure, in which case you get a Check Engine Light, not to mention that its illegal and it will damage your catalyst. Best Regards, Mazda ------------------------------ From: marchil@xxx.net (demo) Date: Tue, 17 Dec 1996 08:51:44 -0500 Subject: Re: Fuel pump questions Don't know how to rebuild a fuel pump but i have bought a Carter P70199 witch is a universal hi pressure external fuel pump, max pressure is 95 psi don't remember the flow rating but it was pretty good, it cost me $125Can about $85Us . >Lets talk about fuel pumps. In specifc, the early model Datsun 280Z pump. >This is a Bosch unit used on the L-Jetronic (and other) EFI systems. The >standard DC motor with a roller vane pump type, mounted outside of tank. I >had a leaking O-ring on the pump, so I took the four screws out and replaced >the ring. Now the pump will run, but it will not develop any pressure (not >enough to open the pressure regulator on the FI system). It's also a monster >to prime now. > >Yes, I did mark the pump housing and assembled it back as original. >Yes, I did reinstall the roller vanes. None of the check valves were stuck. > >I would just say that the pump is bad But, in the past, when ever I opened >one of these pumps and reassembled it, it never worked properly again. > >What's the trick to servicing these pumps?? Last price check was ~$200.00 each. > >What other popular cars (American sold) used this external fuel pump? > >GMD > > // Marchildon@xxx.net // // Alain Marchildon // // 1984 Mazda RX-7 GSL-SE Soon with Vortech supercharger "My toy // // 1989 BMW 325IX "Family car" // ------------------------------ From: cloud@xxx.edu (tom cloud) Date: Tue, 17 Dec 1996 09:30:44 -0600 Subject: Re: more fuel pressure >Dave Zug wrote: >> >> I was given a tip on my car's website, that if i "crush" the pneumatic >> pressure regulator on my 3.1L PFI-T pont. engine, i'll get more fuel for >> a given vacuum. this is because you'd be loading the spring inside the >> regulator. I absolutely am NOT going to do this, but does anyone have >> another way to affect that regulator without buying boosters etc? its >> ONE thing that my ECM CANT alter, that i'd like to. is it >> disassemblable? >> >> ps I have only 40 psi at idle and 60 psi at WOT. >> >> later~ >> dave @:-)-[--< > >I don't know if its disassemblable, but if you run a higher pressure >across the operating range, the adaptive learn will simply correct for >the overfueling. The only way around it is to disconnect the O2 sensor >and raise the pressure, in which case you get a Check Engine Light, not >to mention that its illegal and it will damage your catalyst. > >Best Regards, >Mazda Mazda, While I understand about the 'adaptive learning', don't most engines, at WOT, go to a speed density type mode which utilizes pre-set parameters while ignoring the EGO? If so, wouldn't the net effect be stock performance during normal operation (except idle, where there might be more petrol than the system can adapt for), and improved performance at WOT? Tom Cloud ------------------------------ From: John Hess Date: Tue, 17 Dec 1996 09:52:56 -0600 Subject: RE: sensorless electric motor position detection Actually, most detect wheel lockup by measuring the rotation of the wheels and perform antilock by releasing the brake (or pulsing it) on the wheel(s) that has/have stopped turning (assuming other wheels are still turning). - ---------- From: kleenair@xxx.com] Sent: Tuesday, December 17, 1996 10:20 AM To: diy_efi@xxx.edu Subject: Re: sensorless electric motor position detection Dave Zug wrote: > > anyway, can someone tell me how ABS detects wheel position/movement? > (keep this one for the FAQ!) > > and, is ABS considered EFI related? (be nice) Hi Dave, Most ABS systems use a tooth wheel at the hub. I'm pretty sure most system detect a wheel slip condition by calculating the deceleration rate of the wheel. Although its not EFI, many of the same processes apply to ABS Mazda ------------------------------ From: gofast@xxx.com Date: Tue, 17 Dec 1996 08:57:55 -0800 Subject: new reader: L-jet problems - help wanted. Hi guys - I'm new to this list. I've been going through the archives to see if I can find solutions. Seems like a lot of the topics have been hit on before. I've been hounding the BMW digest for help, and it looks like this is the right place. Here's everything I know so far. Prepare for core dump... * I have a '77 BMW 530i that I've been trying to debug with the following: Engine: rebuilt engine, higher compression than stock (9:5 vs 8.5), 733i cam, ported and polished, 30k miles, fresh valve job Injectors: newly replaced w/ stock injectors- 0.280.150.151 Ignition: Allison XR 700 (replaced points) New fuel filter. All gaskets on intake replaced. Air flow meter: stock meter, bought used, with, I'm sure, a loose/loosened spring. Also have a "new" rebuilt Python airflow meter with the number scratched out, so I cant be sure what it is. However, using this makes the car miss more than using my older unit. Timing: set at 1700 rpm. TPS: I think I set it correctly - top 2 pins close at idle, bottom 2 close when idle pins open (load). I dont have easy access to a professional exhaust analyzer. I might rent one this weekend, and want to try and understand as much as I can beforehand. * Here are the problems and thoughts: a) With 87 octane fuel, pings at high rpm. Does not ping with 93 octane. b) AFM all the way lean (screw all the way out)- gives 1.5%-2% CO, too much HC - cant pass emmissions. c) at rpms above 5000, with 93 octane, seems to hesitate (running out of fuel?) d) idle has some kind of miss. One mechanic has suggested retarding timing to solve a, which will also solve b - reduce HC. Another has suggested more advance to reduce HC. I'm giving up on mechanics... - - Tried more advance last night - still hesitates at higher rpm. - - proffa.cc.tut.fi suggests, in talking about the AFM and injection period, that 'if you loosen the spring too much, the flap will be at maximum prematurely and the engine will run lean at any higher airflow levels'. This might be my problem. BTW, Have not measured fuel pressure as yet. Questions: * How can I set my AFM spring back to stock settings? Is there any systematic way that I can measure voltage or something? * The Bosch fuel injection handbook talks about a rising rate fuel pressure regulator as being an l-jet solution. Any cheap sources for one? Pegasus Racing Supplies has one (MicroDynamics) 2:1 rate for $300! Any cars come with one as stock that I can go to a dealer and get cheaper? * A number of people recommend adjustable FI regulators. The racing cata logs only mention ones for carburated applications. Any thoughts? * Someone suggested disconnecting the spade connector in the glove compartment as an upgrade. This has to do with high altitude usage. What is this doing? Which is normal - connected or disconnected? * My temp guage flickers a bit, once in a while. Is this affecting the ECM's calculations? Should I change the water temp sensor? Thanks in advance. Samir Shah gofast@xxx.com Stamford, CT ------------------------------ From: Peter Shoebridge Date: Tue, 17 Dec 1996 10:01:23 -0700 Subject: RE: Check out the new diy_efi / efi332 web site! Well, I do appologise (he said sending more text encoded messages as I haven't figured what I'm doing wrong!!!) for the problem. I am sure I have the send message in mime format turned off and am not sending in MS Exchange format - so what is the solution? Don't tell me to use Eudora so something else, please. Peter - ---------- From: tom cloud Sent: Tuesday, December 17, 1996 6:39 AM To: diy_efi@xxx.edu Subject: RE: Check out the new diy_efi / efi332 web site! P-L-E-A-S-E turn off the text encoding !! > > >---------- >From: Johnny >Sent: Monday, December 16, 1996 2:14 PM >To: diy_efi@xxx.edu >Subject: Re: Check out the new diy_efi / efi332 web site! > >> From: Peter Shoebridge > >> Looks pretty good, perhaps you should have a go at the diy_efi and efi332 > >> web pages.... > >Peter, those ARE the diy_efi and efi332 web pages!!! Am I missing >something here? > >I meant these pages: > http://efi332.eng.ohio-state.edu/mirror/ >and > http://www.cpsc.ucalgary.ca/~fridman/diy_efi/ > >> I was away this weekend, so I haven't had a chance to test out the >> gnu-win32 b17 cross-compile tools. Should get to that tonight (yeah >> right!!!). > >Sounds great. Keep us posted on how it goes. Although, I have to admit, the >more I play with Linux, the more I like it. ;-) > >-j- > Tom Cloud begin 600 WINMAIL.DAT M>)\^(AD1`0:0" `$```````!``$``0>0!@`(````Y 0```````#H``$(@ <` M& ```$E032Y-:6-R;W-O9G0@xxx.;W1E`#$(`0V ! `"`````@`"``$$ MD 8`9 $```$````,`````P``, (````+``\.``````(!_P\!````8P`````` M``"!*Q^DOJ,0&9UN`-T!#U0"`````&1I>5]E9FE 8V]U;&]M8BYE;F``(P`0````4```!33510`````!X``S !````(P```&1I>5]E M9FE 8V]U;&]M8BYE;F``$P`0```"4````G9&EY7V5F:4!C;W5L;VUB+F5N9RYO:&EO+7-T871E M+F5D=2<``````@$+, $````H````4TU44#I$25E?149)0$-/54Q/34(N14Y' M+D](24\M4U1!5$4N1415``,``#D`````"P! .@$````"`?8/`0````0````` M```"VDT!!( !`#$```!213H@0VAE8VL@;W5T('1H92!N97<@9&EY7V5F:2 O M(&5F:3,S,B!W96(@ M`' ``0```#$```!213H@0VAE8VL@;W5T('1H92!N97<@9&EY7V5F:2 O(&5F M:3,S,B!W96(@xxx.^[*IODP# $````%````4TU44 `````>`!\,`0```!,```!P971E M``@0`0```&4```!7 M14Q,+$E$3T%04$],3T=)4T4H2$5304E$4T5.1$E.1TU/4D5415A414Y#3T1% M1$U%4U-!1T5305-)2$%614Y41DE'55)%1%=(051)341/24Y'5U)/3D@('3\97@%0 GP!: -L![ !X%U'I!G!Y%A!" =4!' =L4) M\"<%0&9I9PAP(%'&=Q' !4!))VT=81\BUG<#8!J@xxx.@*2'0!;$:=!YA< -@ M`F!E;2[U'4%A(M!S(A$A-20C'N+]('8@"X ?4 =Q(^(`P 5 ZG0(<&X@46\- MT!V0)G%Y)2%N;P5 'N8G(07A1>YX$;$:H">'+1Z '8 B8T<$`"8$!O!U=&D" M(#^_%F "("&Q'[ 602=Q=!V DG4>(45U'7!R82MB_RMP!X D,!\B%C 1\!TP M"U"R92$092X*A0J%4!(`!P20,&P*]&QI,3@PP0+1:2TQ-#0-\ S05\-P&E !:!UBQ-!+SO^=6)J-5%#3SF+E%)%2;!#%B!C:RAPGRR0)",H0 ?@124@+Q_P MYR'@xxx.C `D!^PYB$QGS*C,S8T%Q0B# $!-190+4PM12U!_"U34< H M`RAS)#(?N!\BMR.@,&PP;#Y5?C6?/C@UQ3H22D9@;FYY578\Y2TZ$DT"(#]- M-D!%,CKW,W Q,$$6/D,C1.]%_T<)]UF025=+4V5+OTS/3=]5R6X^."4Q0Q8! M;TX0!1!D:2;Q/' Q4D A$&:0;FD7H',N!:!M5>]D\$PX;V]K!" D0A@'H!EX%X0'L EP_\NH&FP'9!AM&)6*,)B]&?/ M]V-3"K @T2YO(55^,4,=,/4D,&\>(4%+D&P/8OENT_TCH2 3<"+0'5 G4 00 M'R'O578N^!8@xxx.@-HX0) <#HO+V+T7F]' M(,HO)U!R`V!R+U5V*,$[>#]Y07=]<&=P:F!C+E1U8P= 9PK >6=P8=PO?@-0 M'K #@xxx.$Z M@"J!/[ MTA^P1K!#88=D>&=N=2T#\&Z]8S%B0" Z@ -@!! M9X'^< ,0+<(& M\&=@9<)K`B#0WR?QA#$B0`>0/IY,!!HA1D%$(EA(Z)O7WY3"& ? M``0@"<$B@"3@2_T)X' N`21@ 'X$Y0::%G41-P;'#1_G6) M8!TR)<0=@7\`3E!PLOYE578?8QU0"U%ID /P)##S:- +@'5XD*,?5!U0,M"' M@xxx.<23@(#LM*57_WFI7AS!L0R BT$,ZHF9P'3J30&:0`-!W@2YP:/]]\!^Q M(1!'`I8=3W\;MS46"PJ%%L$`G2 ``P`0$ `````#`!$0`0```$ `!S @2#2- M.^R[`4 `"# @xxx.B ``````P`--/TW``!: !_.R[ ` end ------------------------------ From: kleenair@xxx.com Date: Tue, 17 Dec 1996 12:27:02 -0800 Subject: Re: more fuel pressure tom cloud wrote: > > Mazda, > > While I understand about the 'adaptive learning', don't most engines, > at WOT, go to a speed density type mode which utilizes pre-set parameters > while ignoring the EGO? If so, wouldn't the net effect be stock > performance during normal operation (except idle, where there might be > more petrol than the system can adapt for), and improved performance > at WOT? > > Tom Cloud Hi Tom, It depends on the calibration strategy of the system. Adaptive learn is not only used for changes in engine characteristics, but also used for changes in fuel composition. If the adaptive learn number is intended to correct for fuel composition, it may be applied to the fuel calculation in open loop mode as well. The only way to know for sure is to hook up the Tech tool and find out if BLM (block learn) automatically goes to 128 (no correction) at WOT. Best Regards, Mazda ------------------------------ From: cloud@xxx.edu (tom cloud) Date: Tue, 17 Dec 1996 12:22:56 -0600 Subject: Re: Fwd: eddy current brake >Hi Tom, > >> ???? On a 4-cycle engine, the cam turns 360 deg for two rotations of >> the crank, and it's the cam timing you're interested in. So 720 degrees >> of crank equals 360 degrees of cam -- now you've got me wondering ..... >> when one looks for ignition timing, are you looking at crank or cam??? > >4 Stroke has cams that make one rev per spark, so timing is from the >cam, BUT the angle of timing advance that is doccumented is given >in crank degrees because that is where it was measured in the >past from the fanbelt pulley. > >Cheers *<<<-| >-- >Kalle Pihlajasaari kalle@xxx.za/ip Are the marks on the damper in 'crank' degrees? I.E. if I put a compass on the crank and found TDC could I mark it using the compass? Tom Cloud ------------------------------ From: James Thorne Date: Tue, 17 Dec 1996 15:18:26 -0600 Subject: Re: oil press "gauge" Actually up thru the 91 model F-series the gauge was real. ie analog and driven by a sending unit. 92 and up are driven by a switch and a resistor to place the reading in the center of the gauge. It can be converted back using the older sending unit and replacing the resistor with a zero ohm jumper. The 'fake' gauge can also be found in other newer Ford and Chevy cars and trucks. James Thorne ------------------------------ From: Steve Baldwin Date: Wed, 18 Dec 1996 10:33:33 +1300 (NZDT) Subject: Re: Check out the new diy_efi / efi332 web site! > > P-L-E-A-S-E turn off the text encoding !! > > Tom Cloud > > Aaarrrrrrrrggggghhhhhh !!!! Please don't quote the whole bloody thing you are complaining about. Geez ! Steve. ------------------------------ From: Kalle Pihlajasaari Date: Tue, 17 Dec 1996 23:58:09 +0200 (sat) Subject: Re: Fwd: eddy current brake Hi Tom, > >> ???? On a 4-cycle engine, the cam turns 360 deg for two rotations of > >> the crank, and it's the cam timing you're interested in. So 720 degrees > >> of crank equals 360 degrees of cam -- now you've got me wondering ..... > >> when one looks for ignition timing, are you looking at crank or cam??? > > > >4 Stroke has cams that make one rev per spark, so timing is from the > >cam, BUT the angle of timing advance that is doccumented is given > >in crank degrees because that is where it was measured in the > >past from the fanbelt pulley. > > Are the marks on the damper in 'crank' degrees? I.E. if I put > a compass on the crank and found TDC could I mark it using the > compass? Now that you got me thinking not sure anymore but I have always assumed that the markings were in crank degrees and it does actually make physical sense as well as we are talking about top-dead-center of the piston and not the valves or something up there. So I would say that the protractor on the fanbelt pulley would be safe. Easy to check though. You know the angle from TDC to static timing about 10 .. 20 deg so you can just check on a handy unit lying around. If you measure 15 it sounds right. Maximum advance of 22 degrees could not reasonably be expected to correspond to a grank advance of 44 deg, that would be a bit much for me. Cheers *<<<-| - -- Kalle Pihlajasaari kalle@xxx.za/ip Interface Products P O Box 15775, DOORNFONTEIN, 2028, South Africa + 27 (11) 402-7750 Fax: 402-7751 http://www.ip.co.za/people/kalle ------------------------------ From: SRavet@xxx.com Date: Tue, 17 Dec 96 16:12:10 CST Subject: cylinder pressure measurement on toyotas? I found this paragraph in a TI application note on engine knock detection using the 320 series of DSP processors: Pressure sensors measure the pressure inside the combustion chamber of a running engine. This direct measurement of the combustion process provides the best signal to analyze to detect engine knock. However, each cylinder requires its own sensor, and individual sensor costs are still relatively high. As a result, pressure sensors are used primarily in research settings. Currently, Toyota is the only manufacturer that installs pressure sensors in production engines. Pressure sensor usage will increase in the future as sensor costs are reduced and automotive companies develop more sophisticated engine control strategies that monitor the combustion process. Does anyone know any more about these pressure sensors that Toyota installs on production engines? - --steve Steve Ravet sravet@xxx.com Baby you're a genius when it comes to cooking up some chili sauce... ------------------------------ From: cloud@xxx.edu (tom cloud) Date: Tue, 17 Dec 1996 16:39:09 -0600 Subject: Re: oil press "gauge" >Actually up thru the 91 model F-series the gauge was real. ie analog and driven by a sending >unit. Wrongamundo! I have the factory blessed schematics (and a '91 F150) -- they show the pressure sensor on 4.9 litre only, all others (not counting diesel) have the cute little switch. There's no drawing for the panel or the instruments theyselfs, so I have my Ford part$ guy checking for me. [just called him -- he went and talked to the shop and said I'm right.... in fact, he's ticked .... his Ranger is the same way. His words don't bear repeating in such genteel company. The 'sperts in the shop said that changing the sender to a pressure xducer would not fix it -- dunno if it was on this list or not that someone said you could remove a resistor behind the gauge and then it would work with the proper sending unit.] Tom Cloud ------------------------------ From: Mazda Ebrahimi Date: Tue, 17 Dec 1996 18:01:52 -0500 Subject: Re: cylinder pressure measurement on toyotas? SRavet@xxx.com wrote: > > I found this paragraph in a TI application note on engine knock detection > using the 320 series of DSP processors: > > Pressure sensors measure the pressure inside the combustion chamber of a > running engine. This direct measurement of the combustion process provides > the best signal to analyze to detect engine knock. However, each cylinder > requires its own sensor, and individual sensor costs are still relatively > high. As a result, pressure sensors are used primarily in research > settings. Currently, Toyota is the only manufacturer that installs pressure > sensors in production engines. Pressure sensor usage will increase in the > future as sensor costs are reduced and automotive companies develop more > sophisticated engine control strategies that monitor the combustion > process. > > Does anyone know any more about these pressure sensors that Toyota installs > on production engines? > > --steve > > Steve Ravet > sravet@xxx.com > Baby you're a genius when it comes to cooking up some chili sauce... The only engines Toyota uses the combustion sensor on is their lean-burn engine. I forget what car it goes in. ------------------------------ From: "Scot A. Sealander" Date: Tue, 17 Dec 1996 18:43:31 -0800 Subject: Re: more fuel pressure tom cloud wrote: > While I understand about the 'adaptive learning', don't most engines, > at WOT, go to a speed density type mode which utilizes pre-set parameters > while ignoring the EGO? Well..... If it is a speed density type, it stays speed density (that is, it still uses manifold pressure, RPM, air temp to determine load. If it is MAF equipped, it still uses the MAF for load..... I think you are misunderstanding closed loop/open loop. At normal operating temp and conditions, the ECM runs closed loop. All this means is that it is using feedback from the O2 sensor. All closed loop means is "with feedback", all open loop means is "without feedback". The air flow (load) is determined the same way, whether it is operating in closed loop or open loop. So if it is MAP equipped, it uses manifold pressure, if it is MAF equipped, it uses the MAF. It does this at either extreme of the sensor, or anywhere in between. The ECM's job is to match fuel flow to airflow (by weight or mass) at the desired AFR. Usually, this is 14.7 to one. (Keep in mind that the O2 sensor just happens to transition at this AFR.) Simply put: Injector PW = Amount of air in cylinder * Inverse AFR term * Injector constant to make it work, or: PW = Load * IAFR * Injk What happens is that the system may not be perfect, and may have some error in it. For instance, if someone jacks the fuel pressure up, then the normal injector constant will be wrong, and it will deliver more fuel than intended. So we can add a correction term for trimming the fuel equation. PW = Load * IAFR * Injk * closed loop trim Now we need a method for feedback to make the trim value correct fuel to the right value. This is where the O2 sensor plays a part, in closed loop mode. If the trim value is slightly above a neutral value, the O2 sensor should show a rich value, if it is slightly below neutral trim, the O2 sensor should be a lean value. The ECM has a strategy to do this dithering of the trim value to determine if it is delivering the right amount of fuel. If it isn't, it will attempt to correct it. I will leave it up to you to figure this out..... So if the O2 Sensor does not flip rich/lean, the ECM knows which direction it needs to correct, and will correct for that. It has both short term and long term correction factors. So now: PW = Load * IAFR * trim * short term corr * long term correction Notice that to be in closed loop, the AFR term has to be at 14.7. When the engine starts, the engine is in open loop, and the AFR term can be used just like the choke on a carburator. Set it rich, and it will deliver more fuel at start, and this value can then be decayed as it warms up. For WOT, the 14.7 value is much too lean for the engine, and the ECM will go open loop (just meaning no feedback), and the AFR will be set richer for best power. This AFR usually comes from some tables that have temp and RPM corrections to this AFR. Now with it being in PE, the O2 sensor is not useful for the correction strategy, so the trim will be set neutral, and that part of the code will be skipped. But the O2 sensor is still sampled, and shows up in the ALDL stream, so ypu can see the value. > If so, wouldn't the net effect be stock > performance during normal operation (except idle, where there might be > more petrol than the system can adapt for), and improved performance > at WOT? Not necessarily. Does the engine need more fuel at WOT? ;-) I have seen various schemes on how to correct while in PE (power enrichment). The correction factors are used to add fuel if the correction is to add fuel. If the correction is normally removing fuel PW, the correction may or may not be used..... So go get an ECM and figure it out! I did not mean to ramble this long. It may not be entirely clear, but hope that is useful. Scot Sealander Sealand@xxx.com ------------------------------ From: Charles Napier Date: Tue, 17 Dec 1996 18:51:34 -0800 Subject: Re: Fwd: eddy current brake tom cloud wrote: > > >Hi Tom, > > > >> ???? On a 4-cycle engine, the cam turns 360 deg for two rotations of > >> the crank, and it's the cam timing you're interested in. So 720 degrees > >> of crank equals 360 degrees of cam -- now you've got me wondering ..... > >> when one looks for ignition timing, are you looking at crank or cam??? > > > >4 Stroke has cams that make one rev per spark, so timing is from the > >cam, BUT the angle of timing advance that is doccumented is given > >in crank degrees because that is where it was measured in the > >past from the fanbelt pulley. > > > >Cheers *<<<-| > >-- > >Kalle Pihlajasaari kalle@xxx.za/ip > > Are the marks on the damper in 'crank' degrees? I.E. if I put > a compass on the crank and found TDC could I mark it using the > compass? > > Tom Cloud They are in crank degrees. Charlie ------------------------------ From: dave.williams@xxx.us (Dave Williams) Date: Tue, 17 Dec 1996 19:11:00 +0000 Subject: RE: Check out the new diy_efi / efi332 web site! - -> Content-type: APPLICATION/OCTET-STREAM - -> Content-transfer-encoding: X-UUENCODE - -> - -> begin 600 WINMAIL.DAT - -> M>)\^(@`6`0:0" `$```````!``$``0>0!@`(````Y 0```````#H``$(@ <` - -> M& ```$E032Y-:6-R;W-O9G0@xxx.;W1E`#$(`0V ! `"`````@`"``$$ - -> MD 8`9 $```$````,`````P``, (````+``\.``````(!_P\!````8P`````` AAARGH! It's BAAAAAAAAAAAAAACK! ------------------------------ From: dave.williams@xxx.us (Dave Williams) Date: Tue, 17 Dec 1996 18:38:00 +0000 Subject: Re: oil pumps (not efi) - -> moving parts separated under higher loads. That's why heavy grease, - -> and not 5W15 oil, is used in wheel bearings. Rolling element bearings are in contact by definition. The lubricant is mostly for the benefit of the bearing cage. The grease in a wheel bearing does not physically separate the load surfaces like on a plain bearing. - -> also maintain a reasonable film strength. Also, nobody mentioned - -> that the circulating oil is splashed against the bottom of *very* hot - -> pistons in order to cool them. Most of the heat in motor oil comes - -> from contact with the hot pistons. The pistons contribute little heat to the oil of most engines. A few turbocharged gas engines and some Diesels spray oil on the underside of the piston for cooling, but the majority of engines depend on contact with the relatively cool cylinder wall and the cool intake charge. Dry sump engines, such as Harleys and some other motorcycle and many racing engines, don't put enough oil in the crankcase to cool much besides the bearings. Plain old oil shear in plain bearings can raise the temperature of the oil in the journal to over 300F under racing loads, even on relatively low output engines. ------------------------------ From: dave.williams@xxx.us (Dave Williams) Date: Tue, 17 Dec 1996 19:31:00 +0000 Subject: Re: oil pumps (not efi) - -> > With the same spring, both the standard and high volume pumps will - -> flow >the same amount of oil at the same running pressure. None of - -> the "high >volume" ever makes it out of the pump. > This is true, but with all else equal, the high volume pump will > develop more pressure at a given RPM, hence it will pump more oil, > simply because its pumping more volume through the same clearance > space. No additional oil is *getting* to a clearance space. It's never leaving the pump. The only way you're going to move more oil through the bearings is to increase the pressure. ------------------------------ From: "George M. Dailey" Date: Tue, 17 Dec 1996 20:58:37 -0600 (CST) Subject: Re: more fuel pressure Well Cloud, I would say this is true except for one tiny fact. When GM (and those other fellas) established WOT fuel maps, they did it to maximixe power. There are (were) no WOT EPA standards to meet. The skys's the limit. Assuming they made a mistake on there WOT maps, there might be improvements in altering the A/F ratios. One Hi-perf. book I read, said that if there was any SINGLE item on todays computer controled cars that could be changed (without breaking the emission laws) to increase their performance, one of the hundreds of engineers on site would have done it. Performance sales! Would you by a car that advertised, "The Lowest rated horsepower cars in the world...and damn proud of it!"? When the FAQ is completed, line one should be: Q- Can I raise my fuel pressure to inscrease my WOT power? A- No. If you have a stock automobile, and its is working properly, increasing fuel pressure (with no other changes) will not increase power. Good luck, GMD At 09:30 AM 12/17/96 -0600, you wrote: .. > >While I understand about the 'adaptive learning', don't most engines, >at WOT, go to a speed density type mode which utilizes pre-set parameters >while ignoring the EGO? If so, wouldn't the net effect be stock >performance during normal operation (except idle, where there might be >more petrol than the system can adapt for), and improved performance >at WOT? > > >Tom Cloud > ------------------------------ From: "George M. Dailey" Date: Tue, 17 Dec 1996 20:58:43 -0600 (CST) Subject: Re: oil press "gauge" Fake OEM gages? The end is truely near. At 03:18 PM 12/17/96 -0600, you wrote: >Actually up thru the 91 model F-series the gauge was real. ie analog and driven by a sending >unit. 92 and up are driven by a switch and a resistor to place the reading in the center of the >gauge. It can be converted back using the older sending unit and replacing the resistor with a >zero ohm jumper. > >The 'fake' gauge can also be found in other newer Ford and Chevy cars and trucks. > >James Thorne > > > ------------------------------ End of DIY_EFI Digest V1 #387 ***************************** 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".